How to read nutritional labels

Knowing how to interpret nutrition labels will help you to make healthier food choices and eventually will lead to an overall better you. People around the world examine food labels for a range of reasons. Although these reasons might differ between the populations, the important thing is to know how to read correctly the labels. Below we will explain how you can build label reading skills easily but effectively. I will use also examples in order to make it more understandable.

1)Start here: The information you will find in this top section of the product will vary since each product contains specific information on serving size, nutrient information and calories. The important thing here is to note the serving size/portion as well as the amount of servings included in the packet. After that, consider how many servings you are eating from this food. In the sample provided, 1 serving equals to 1 slice or 47gr while the whole packet contains 6 slices.

2)Check the total calories (and the calories from fat) per serving: Calories represent a measurement of how much energy you consume from the serving size of this food. This section can help you control your weight since you will know approximately how much calories you consume. However, you need to remember that the total calories you are consuming from this food will be dependable to the amount of servings you are consuming. In the example I provided, there are 160kcal per one slice. According to FDA, there is a general guide to calories for foods. Check this guide below:

• 40 Calories is determined as Low
• 100 Calories is determined as Moderate
• 400 Calories is determined as High

Also the calories from fat for this serving size are 90kcal. This means that the most of the calories of this product are coming from fat.

3) Eliminate these nutrients: The nutrients that are listed in the light blue table are the ones that people eat in adequate amounts and sometimes even more than the recommended. Eating plenty of fats, saturated fats, trans fats, cholesterol as well as sodium is possible to increase the risk of some diseases, like coronary disease, high blood pressure and some kinds of cancers. For this reason, health professionals recommend you to keep your intake of these nutrients as low as possible.

4) Get plenty of these nutrients: Most people do not consume adequate amounts of these healthy nutrients. Specifically, fiber, vitamins A, C, calcium, iron and the rest minerals are low in western diets. Health experts are forcing people to eat adequate amounts of these nutrients since they can be beneficial for your health and sometimes may lower the risk of some other conditions. For example, by consuming enough calcium, you may reduce the risk of osteoporosis, a situation that results in fragile bones alongside with ageing. What is more, diets rich in fiber have beneficial effect on bowel function and weight management. Furthermore, eating a diet high in fruits and vegetables (rich in vitamins, minerals and fiber) can reduce the risk of heart diseases since these foods are low in saturated fats and cholesterol.

5) Understanding the % Daily Value: This section shows the percentage of every nutrient included in one serving of this specific food, in accordance to the daily recommended amount. According to FDA regulations, if you want to consume low amounts of a specific nutrient, such as trans fats, saturated fats, cholesterol and sodium, opt for foods with a %DV of these nutrients as low as possible. On the other hand, if you want to increase your intake of some specific nutrients such as vitamins, opt for foods of a high %DV for these healthy nutrients. FDA has mentioned that “5% or less is low” and “20% or more is high”.

In our example, we can see from the table that, this food is low in dietary fiber (3%<5%), and in vitamins A and C (0% and 4% respectively). However, it is a good source of calcium (45%>20%). The main disadvantages of this product is that the section of the “limit these nutrients” is relatively high. For example, fat %DV is 15%>5%. What is more the saturated fats seem also to be high with a %DV of 11%>5%.

It is worth to note that the %DVs are based on a 2000 calorie diet. This amount differs from person to person according to gender, age and physical activity level. You may not know how many calories you need to take from your food to maintain your body weight, like most people. However, you can still use the %DV as a reference whether you consume less or more that 2000calories. This is because, the %DV only tells you if a food is high or low in a specific nutrient.

Conclusion

Last but not least, additionally to the nutrition labels, the most of the foods today offer a content claim from the manufacturer. You will find these claims on the package of the product provided from the manufacturer. FDA examines strictly these claims though. Below you can find some claims as examples with their meanings:

• Sugar free=Contains Less than 0,5g of sugar,
• Fat free=Contains Less than 0,5g of fat
• Low fat=Contains 3g of fat or less than that

“Egg-excellence” (from a health & performance perspective)

The most athletes know that protein is critical in the muscle-building process. Every tissue in the human body consists of proteins that are constantly being broken down and need to be replaced in the body. Eggs are one of the best sources of protein for strength and conditioning athletes; they contain all of the amino acids an athlete needs to gain size and strength. In fact, the protein from eggs is even used in some types of protein powders lately. But let’s find out everything about eggs, from both a health and a performance perspective.

The truth with cholesterol (Science VS History):

It’s true that when you compare egg yolks to other foods they are relatively high in cholesterol, as the average egg contains anywhere between 190 and 215 milligrams. Cholesterol is something that many people should be concerned about, but not so much in the case of eggs. Studies have shown that regularly eating eggs can actually lower your low density lipids (that’s “bad” cholesterol) and raises high density lipids. The dangers of a high cholesterol diet may also have been exaggerated in the media as some studies have proven that people who maintain a low cholesterol diet still may have elevated cholesterol levels. This is because cholesterol actually serves several important functions in the body, and when you don’t get enough, it makes its own. In fact the liver produces about the two thirds of the body’s cholesterol, with dietary intake having very little impact on the overall levels. Limiting dietary cholesterol intake is important but the real danger comes from other risk factors, such as saturated and trans fat in addition to a sedentary lifestyle, overeating and smoking, as research suggests (1). These are greater factors in increasing cholesterol and causing heart related problems than any typical intake of egg yolks. It doesn’t make much sense to separate egg yolks to avoid the cholesterol while eating deep fried fatty foods, pizza and other junk in a normal western diet.

The benefits:

An average egg weighs about 60 grams and is composed by 11% of the shell, 58% of the egg white and 31% by yolk (2). The egg white consists primarily of water (88%) and proteins (9%), and the yolk consists of water (51%), lipids (31%) and protein (16%) (2). According to the U.S. Department of Agriculture’s nutrient database, each egg contains 6.28 grams of protein, 72 calories, 4.75 grams of total fat, and small amounts of vitamins and minerals. The key nutrients found in eggs, such as vitamin D, vitamin B12, folic acid and selenium have been associated with the prevention of chronic conditions such as heart disease, high blood pressure, impaired cognitive function and congenital anomalies. A UK study has found that adults who consumed three or more eggs per week had significantly higher intakes of vitamin B12, A and D, niacin (B3), iodine, zinc and magnesium, compared with those that were not consuming eggs (3). The relatively high content of eggs in vitamin D is remarkable, since few foods are recognized as good sources of this vitamin. Overall, the nutritional composition of eggs can be changed via the feed given to hens. This is the case, for example, eggs with high content of docosahexaenoic acid (DHA), an omega-3 fatty acid important for brain development, normal vision, heart health and certain other physical functions (4). Moreover, these fats are desirable because they help in controling hormone regulation and cellular growth in the body.

Thus, YES, eggs are indeed wonderful for your body and brain. The harmful effects of eggs have been completely overblown (5). But there is also another story to eggs. For instance, scientists have known that reduced brain serotonin function is involved in stress-related disturbances and may occur under conditions of chronic stress. We also know that serotonin production depends on the availability of tryptophan (TRP). Recently, an egg protein hydrolysate (EPH) was developed that showed a much greater effect on brain TRP availability than pure TRP and other TRP-food sources.

How to cook eggs?
Hheating the egg does cause indeed some chemical changes that damage some of the nutritional profile of the egg, but not too much to be concerned about. If you are considering eating raw eggs, then although raw eggs are very easy on the digestive system, it is very common to experience some stomach discomfort when starting a new raw egg regimen. For this reason i would recommend to enjoy your eggs cooked!

Recommendations:

So far so good with the egg quality, composition and health benefits. Let’s talk about recommendations. Here comes the question “how many eggs per day?”. As we already mentioned, saturated and trans fat may actually be a larger contributor than eggs to cholesterol levels. A single egg contains a gram or two of saturated fat, so eggs are fine in moderate amounts, but you should avoid eating too many eggs because of possible consequences to the cardiovascular system. Generally this is not a problem. You would have to eat more than 10 eggs a day to consume too much saturated fat. However, you may want to monitor your egg consumption if you are also eating bacon, red meat, butter and other foods high in saturated fat. Also, as a nutritionist i would not answer this question with a specific number. It’s like with fruits. I can not recommend a specific amount for everyone without knowing the diet (other sources from cholesterol when recommending for egg consumption), the lifestyle, the goals and the exercise training each follows. However, just for the record, the UK Food Standards Agency no longer places a limit on the number of eggs that you should eat

References:

1) Barraj et al. (2009). A comparison of egg consumption with other modifiable coronary heart disease lifestyle risk factors: A relative risk apportionment study. Health Sciences practice. 29(3):401-15
2) Food Standards Agency (2002). McCance and Widdowsonsâ??s The Composition of Foods, 6th summary edition. Cambridge: Royal Society of Chemistry.
3) Ruxton CHS et al. (2010). Nutritional and health benefits of consuming eggs. Nutrition & Food Science 40:263-279.
4) European Food Safety Authority (2010).
5) Egg-cellent news for most, but not those with diabetes. The harmful effects of eggs were overblown, but the studies show that people with diabetes should still limit how many they eat. Harv Health Lett. Jul (2008) ;33(9):6.
6) Nakamura Y, Iso H, Kita Y, et al. Egg consumption, serum total cholesterol concentrations and coronary heart disease incidence: Japan Public Health Center-based prospective study. Br J Nutr. Nov (2006) ;96(5):921-928.

Fructose: Friend or Enemy?

Carbohydrates in your body

Lately the sugar is increasingly used as a scapegoat for America’s and Europe’s obesity problem. But what about fructose? Is there a valid base for the fructose-bashing trend? Let’s see first how carbohydrates are processed in the body.

At first point you eat or drink something that is high in carbohydrates. The source could be “complex” like oats, quinoa, beans or even vegetables. The carbohydrates from these sources will be broken down in the gut and absorbed as the simple sugar glucose. Table sugar, syrups and some natural foods contain “simple” carbohydrates, like sugars. For example, milk contains the sugar lactose, which breaks down into glucose and galactose. Table sugar (sucrose), breaks down into glucose and fructose (50/50). Foods like fruit and high fructose corn syrup (1) also provide fructose and glucose, but fructose is slightly higher (about 55/45). But note that HFCS and the table sugar usually have comparable sugar composition and metabolic consequences in the body. Specifically speaking, when you eat carbohydrates, they are absorbed as simple sugars and sent to the liver first. For processing glucose, the liver has an orderly and controlled system and, based on body’s needs, it will do different things with the amount of glucose you have consumed. For example, after an intense lifting session, your liver may decide to use glucose to replace depleted carbohydrate storage (the so called glycogen) in the muscles. However, if your liver is doing a lot of processing and needs energy for itself, the glucose may be used to make more energy molecules (ATP). In contrast, if you have been sitting and munching all day, the liver will turn glucose into fat for long-term storage. Fructose is also sent straight to the liver, but it is dealt with in a more chaotic process once it gets there. Because the structure of fructose is a bit more complicated, to state it simply, the easier thing for the liver to do with fructose is to make fat from it. Scientists have speculated for a long time that the liver does this, but there was little research to support this notion, until recently.

The latest research-based information on fructose

In the literature, there is evidence that fructose turns to fat much easier than other sugars. Specifically, a recent research from the University of Texas Southwestern Medical Center, fed healthy people breakfast drinks containing three different “sugar combinations” followed by a carefully controlled lunch. They did this over several weeks. In one test the drink contained 100% glucose, in another the drink was half glucose half fructose (which is what you will find in ordinary sugar). In the third condition, the subjects got a drink that was 25% glucose and 75% fructose. The researchers were interested in how fast the sugars in the drink turned to fat in the liver as well as how this morning meal will influence the metabolism of foods eaten later in the day (the subsequent lunch for example). In the findings, the researchers found that fructose got “made” into fat more quickly than other sugars. And for the second thing, they found that when fructose was eaten with fat (junk food), the fat was much more likely to be stored rather burned.

The theory behind all this notion, that fructose increase appetite, is that fructose does not elicit an insulin & leptin response, and thus does not blunt appetite. But, hold on a second. People do forget that most fructose in both the commercial and natural domain has an equal amount of glucose attached to it. You would have to go out of your way to obtain fructose without accompanying glucose. Thus in studies directly comparing the effect of fructose and glucose preloads on subsequent food intake, one showed no difference (2), while a recent literature review on fructose’s effect on satiety found no compelling case for the idea that fructose is less satiating than glucose, or that HFCS is less satiating than sucrose (3). In general, both compounds have substantial research showing not just their ability to elicit an insulin response, but also their suppressive effect on appetite (4-5). In the only study that fructose was linked to a greater next-day appetite in humans, 30% of total daily energy intake was in the form of free fructose (6). The amount of free fructose provided to the subjects was 135g, which is the equivalent of 6-7 soft drinks (Just for the record, a medium banana has 7g of fructose, an apple 12g of fructose and 2 cups of strawberries 4g of fructose). Is it really that ground-breaking to think that consuming a half-dozen soft drinks per day is not a good idea? In my opinion, demonizing fructose without mentioning the dose-dependent nature of its effects is misleading and dishonest. Like everything else, fructose consumed in gross chronic excess can lead to problems, while moderate amounts are neutral, or beneficial in some cases (7).

Summing up

Taking everything into consideration, although examples of pure fructose causing metabolic upset at high concentrations abound, especially when fed as the sole source of carbohydrate, there is no evidence that the ordinary fructose-glucose sweeteners do the same. Thus studies using extreme carbohydrate diets may be useful for probing biochemical pathways, but they have no relevance to the human normal diet. In general, the upper safe limit of fructose per day (all sources considered) depends on a number of variables, such as an individual’s physical activity level and lean body mass. Although there is research suggesting that up to 90g per day has not negative effect in fasting triacylglycerol or body weight, there is some other research suggesting that the safe range is between 25-40g per day (8). If we think that both sides are biased, the middle figure between the two supporters, is approximately 50g for active adults. Once again, it is important to mention that the big picture solution is managing the total caloric balance with a diet that contains minimally refined foods and sufficient physical activity.

References:

1) http://en.wikipedia….tose_corn_syrup
2) Spitzer L, Rodin J. Effects of fructose and glucose preloads on subsequent food intake. Appetite. 1987 Apr;8(2):135-45.
3) Moran TH. Fructose and satiety. J Nutr. 2009 Jun;139(6):1253S-1256S. Epub 2009 Apr 29.
4) Melanson KJ, et al. High-fructose corn syrup, energy intake, and appetite regulation. Am J Clin Nutr. 2008 Dec;88(6):1738S-1744S.
5) Soenen S, Westerterp-Plantenga MS. No differences in satiety or energy intake after high-fructose corn syrup, sucrose, or milk preloads. Am J Clin Nutr. 2007 Dec;86(6):1586-94
6) Teff KL, et al. Dietary fructose reduces circulating insulin and leptin, attenuates postprandial suppression of ghrelin, and increases triglycerides in women. J Clin Endocrinol Metab. 2004 Jun;89(6):2963-72
7) Dolan LC, et al. Evidence-based review on the effect of normal dietary consumption of fructose on development of hyperlipidemia and obesity in healthy, normal weight individuals. Crit Rev Food Sci Nutr. 2010 Jan;50(1):53-84
8) Sánchez-Lozada LG, et al. How safe is fructose for persons with or without diabetes? Am J Clin Nutr. 2008 Nov;88(5):1189-90

A Guide to Alcohol for “Muscleheads”

Introduction-Alcohol:

In general, alcohol has a positive and negative side ; In low doses ( i.e a glass of wine per day) has potential health benefits. However, in high doses, it makes us feel like wreck cars. Historically, alcohol has been blamed for many of the world’s tragedies and problems, from the fall of the Roman Empire (1), to the disbanding of many families. Alcohol (a broader term for ethanol, or ethyl alcohol) is one of those substances that blurs the line between food and drugs. Actually it’s a macro-nutrient like carbs, protein and fat with seven calories per gram. However, contrary to the other 3 nutrients, alcohol it’s not an essential nutrient. That means that the body can not use ethanol for fuel (survival and growth).

Alcohol and Thermogenesis:

There is ongoing interest on alcohol calories, and people are wondering if alcohol calories count or not. This is because drinkers weigh less than no-drinkers (2) and studies showing accelerated weight loss when fat and carbs are exchanged for an equivalent of calories from alcohol. Specifically, one study compared two weight-loss diets (1500kcal per day). In one diet, subjects got 10% of their total calories from white wine while in the second group the 10% of their calories was coming from grape juice (4). After three months the white wine group lost almost a kilogram more of total body weight, although the difference was not statistically significant. No one knows how this would work out in a long period of time. To explain this phenomenon, I came across with some ideas below.

Well alcohol has 5.7 calories due to the thermic effect of food (TEF) which is 20% of the ingested calories. This makes the TEF of alcohol similar to that of Protein (20-35% depending on aminos composition). However, is higher TEF the reason that regular drinkers have a lower body fat percentage? It’s unlikely that the effect on body weight in the general population can be attributed only to the high TEF of alcohol. An other explanation is that alcohol consumption decreases food intake in the long term as research has shown so far(3). Another explanation is that regular alcohol consumption affects nutrient partitioning favourably via improvements in insulin sensitivity. Specifically, alcohol’s activation of AMPk, a metabolism-regulating enzyme, helps you lose fat by increasing insulin sensitivity (5).

Effects of alcohol in muscle mass and testosterone:

A lot of people are wondering if alcohol destroys muscle mass. Well, maybe. But you have to drink a lot to reach this level. Research so far, on alcohol’s effect on muscle-protein metabolism is on heavy alcoholics who consume more than 100gr of ethanol per day. This means more that seven drinks per day. Almost 2/3 of these people end up with a condition called “alcohol myopathy”. This condition is characterized by muscle weakness and atrophy, frequent falls, walking difficulties. The high volume of alcohol tends to displace essential nutrients, which means casual drinkers aren’t likely to lose their hard-earned muscle mass There is another study though, in which it was shown that 2-3 beers per day decreased testosterone levels by 6.8% during a 3 week period (6).  However, it’s worth to mention, that this consumption of beer increased “dehydroepiandrosterone sulfate” (DHEAS) by 16.5%. A review in 2003 suggests that low serum levels of DHEAS may be associated with coronary heart disease in men, but it was insufficient to determine whether DHEA supplementation would have any cardiovascular benefit. Thus, DHEAS elevation might have a potential to decrease cardiovascular disease risk.

Alcohol, performance and recovery:

This topic is a bit hard to investigate since it is difficult to get approval for a study in which athletes get drunk after a workout. It’s even harder to get approval for a study to investigate getting drunk before a workout. However, some kind of studies on this topic have been done. From the few studies available, in one study (7), subjects were given the equivalent of six drinks and then tested for strength and endurance. Contrary to what researchers expected, the alcohol had no negative effect on any of the strength tests. In addition to that, there was no increase in creatine kinase which is an indicator of muscle damage.

When it comes to recovery, a study looked at the acute effect of alcohol intoxication on post-exercise hormonal response, using professional weight lifters (8). In this study, subjects were divided in two groups. The first one was given the equivalent of five drinks after a workout. The researchers examined all hormonal reactions for the next 5 hours. Surprisingly, no differences were seen in Testosterone and other related hormones in either group, except from a modest increase of cortisol levels. When it comes to post-workout strength, research has been shown mixed results. In one study, where it was used eccentric training to examine the alcohol effects post-workout, researchers noticed an impaired recovery in the trained muscles. However, we should take into account that the program followed was really rough, which itself is hard to recover from. A different study that looked at the results of post consumption alcohol (120g) of exhaustive endurance training, noticed a significant decrease of testosterone levels which were suppressed till the next day. Taking into consideration all these information, you have to be either a heavy drinker or undertaking extremely tough workouts, in order to have a problem with alcohol. Unless you are in a habit of going bar-drinking every day after 50reps of max eccentric leg extensions, this stuff does not apply to you.

Small advices to prevent fat gain when drinking:

Now that you have all the information you need to know about alcohol it’s time to learn how alcohol works for fat loss, or at least to prevent fat gain. Especially when you do not have to count calories and while drinking as much as you want. Just be aware that there are better and worse choices out there.

1) For this specific day, limit fat and carbs to 0.3g/kg of body weight and 1,5g/kg b.w respectively.
2) Get all carb calories from veggies and tag-along carbs in protein sources.
3) Try to select good sources of alcohol such as: dry wine (almost 0g of carbs) vs sweet wine (4-6g of carbs). Other drinks with zero carbs are gin, rum, tequila, vodka and whiskey.
4) Eat as much protein as you want. Due to the limit on dietary fat, you need to get your protein from lean sources. These are: cottage cheese, protein powder, chicken, turkey, tuna and egg whites.
5) If you are following a fat loss programme, this method should be limited to once per week.

Apply this with good judgement and don’t go out and do something stupid now. Remember, this a short-term strategy for those that want to be able to drink freely without significantly impacting fat loss progress or causing unwanted fat gain. From an overall perspective, if you don’t already drink, there is no reason to start. If you drink a lot, you risk a lot. And if you drink in moderation by following simple guidance like the steps above, there is no reason to quit.

References:

1. http://www.abc.net.a…hol/alcohol.htm
2. Yeomans et al. 2010. Alcohol, appetite and energy balance: Is alcohol intake a risk factor for obesity?
3. Kokavec, 2008. Is decreased appetite for food a physiological consequence of alcohol consumption?
4. Flechtner-Mors M, et al. Effects of moderate consumption of white wine on weight loss in overweight and obese subjects. Int J Obes Relat Metab Disord. 2004
5. McCarty MF. Does regular ethanol consumption promote insulin sensitivity and leanness by stimulating AMP-activated protein kinase? Med Hypotheses. 2001
6. Burke LM, et al. Effect of alcohol intake on muscle glycogen storage after prolonged exercise. J Appl Physiol. 2003
7. Poulsen MB, et al. Motor performance during and following acute alcohol intoxication in healthy non-alcoholic subjects. Eur J Appl Physiol. 2007
8. Koziris LP, et al. Effect of acute postexercise ethanol intoxication on the neuroendocrine response to resistance exercise. J Appl Physiol. 2000

Weight training, Protein and Women

When it comes to women and weight training, there are a lot of misconceptions. The first thing that women think when they are introduced to the weight training world, is bulky bodies without femininity. The fact is that weight training can be very beneficial for all women, particularly those with fat loss goals. In addition to that, recent research has shown also the importance of protein consumption when combining weight training and a fat loss program. This article will explore some of the most common misconceptions of weight training for women and will provide and insight of interesting facts about why women should include weight training and protein to their daily weight loss plan.

The most common misconceptions surrounding women and weight training are:

1)Women who lift weights and eat protein will get big bulky muscles.
2)The hard muscle that we will  gain, will turn to floppy, flabby fat if we stop lifting weights.
3)Women should lift weights at high repetitions and low weight for ‘toning’.

Women who lift weights get big bulky muscles
To explain it in an easy way, most women do not have the high levels of testosterone and HGH (human growth hormone) required to increase lean muscle mass dramatically. With strength training we can all replace muscle lost through ageing and (depending on our genetics) most probably add on a further couple of kilograms of lean muscle mass if we are lucky. I say lucky because more muscle means a faster metabolism, faster fat burning and a major slowdown of the ageing process. Specifically, research has shown that if we increase our lean muscle mass by 1.4kg we also increase our resting metabolism by 7% and our daily calorie requirements by 15% (1). Specifically this study concluded that a basic strength program resulted in 1.4kg more muscle, 1.8kg less fat, and 370 more calories per day food intake! Other studies have also shown that the increase in metabolism is between 6-8%. This clearly means that the more muscle the better reducing fat accumulation. That also means that women can save tremendous amount of time spending at the gym.

Ok, so if weights don’t lead to bulky muscles, why do women body builders look so big? The answer to that is easy. Their use of anabolic steroids, loads of food, super genetics and very intense training programs can result in enhanced muscle growth. This is not happening to the average woman that trains 2-3 times per week and follows a low calorie diet plan. Thus taking part to “Olympia” is not so easy as it seems in the magazines…

Lean muscle gained will turn to floppy, flabby fat if we stop lifting weights
Muscle will not turn into fat; it is as impossible as turning wood into steel! However, if we stop  training and we still eating the same amount of food we were eating while we were training, we will naturally put on fat. This is because when we stop exercising we begin to ‘lose’ muscle (use it or lose it!) and our metabolic rate declines causing a natural decrease in our daily energy needs. Any excess calories, regardless of their source, is then stored as fat.

Women should lift weights at high repetitions and low weight for ‘toning’
Well so far we can understand why anaerobic exercise is necessary. However, aerobic is also necessary for different reasons. But let’s make it clear. ‘Muscle tone’ comes from having adequate amounts of muscle that can be seen under low levels of body-fat. Obviously to do this we need first to lift weights so that we have enough muscle visible, however, lifting weights at high repetitions and low weight actually uses our aerobic system and trains our muscles for endurance instead of strength and hypertrophy (muscle gain) according to ACSM guidelines. So to make our muscles tight and ‘toned’ we need to ‘build muscle’ and this can only happen if our muscles are placed under sufficient overload (lifting relatively heavier weights). Overloading our muscles is best achieved by regularly and progressively increasing the amount of the weight we lift. As our body adapts (gets stronger) to lifting a certain weight that weight becomes easier for us to lift and we will need to lift more weight to create an overload. In other words, it is all about the stimulus we provide to our bodies. By using lighter weights and doing the exercise more times we force our body to ‘endure’ more weight but there will no longer be an overload or the advantageous stimulus. Thus if you are about to lift light weights, it is better to keep on running on the treadmill, if you are also enjoying it more than lifting!

How protein can help in the weight loss process
An interesting research (2) was published just a few months ago and is worth mentioning. In this reseach two very important scientists took part and their names are Dr. Tarnopolsky and Dr. Phillips. In the study researchers studied the effects of protein on body composition in premenopausal overweight and obese women who were following an exercise program and were under a low calorie diet. The protocol specifically, included 3 groups of women (n=30 each group), all three groups in a low calorie diet. The first group was high in protein consumption, the second group was under adequate amount of protein and the third with low consumption of protein. The study was ongoing for 4 months and the researchers concluded that: Although all three groups lost fat, the the first group lost the most, while it was also mostly from the abdominal tissue. Also this first group of women added some lean mass when compared to the group of middle consumption of protein. It is also worth saying that the third group with low protein intake actually lost some lean mass. Finally, it is worth mentioning that the first group brought the best results regarding the bone health of these women. Thus it is very clear that a diet high in protein while keeping calories low, is more effective and has better results from all the perspectives of view.

Conclusion
So should you do weight training and eat protein? If you want to lose weight, burn more fat, look and feel stronger, have stronger bones and be able to eat more without putting on extra weight from fat, ABSOLUTELY! Weight training replaces lost muscle tissue which means you will have a faster metabolism, faster fat burning and less chance of getting fat! Muscle is lean, hard and small whilst fat is flabby, soft and mainly big.. the choice is yours 😉

What we can see here is 2,5kg of muscle and 2,5kg of fat. It’s obvious that fat takes much more space when compared to the same amount of muscle. If you have heard people saying that started exercising, have remained at the same kg but clothes are better fitted on them, then now you know the reason, it’s called body re-composition 

References:

1) Campbell et al. (1994). Increased energy requirements and changes in body composition with resistance training in older adults.The Amer J of Clinical Nutrition
2) Tarnopolsky et al.(2011). Increased consumption of dairy foods and protein during diet- and exercise-induced weight loss promotes fat mass loss and lean mass gain in overweight and obese premenopausal women. J of Nutrition.
3) Schmitz et al. (2003). Strength training for obesity prevention in midlife women. International Journal of Obesity, 27, 326-333

Sport Drinks: Wash your mouth out (or not)?

Three to four years ago, exercise scientists said that they have stumbled on an amazing discovery for endurance athletes.Specifically, athletes could improve their performance in intense bouts of exercise, lasting an hour or so, if they just rinse their mouths with a carbohydrate solution, without even swallowing it. From then, more and more research is being conducted on this topic to find out how and when exactly this amazing technique works!

But let’s put things on a row…It is already known that the consumption of sports drinks during prolonged exercise (> 1 hour) improves athletic performance (1,2). Specifically, these drinks replace the energy and fluids lost during exercise by providing a ready fuel for the working muscles. Several studies, however, have also reported that ingestion of carbohydrates before and during exercise of a relative short (~1h) and intense nature (>75%VO_2max) leads to performance improvements (3,4,5). Moreover, benefits to performance have been reported in both cycling (3,4) and running (5). It has been suggested that a higher glucose oxidation rate caused by carbohydrate ingestion and that explains the improvement. However, Jeukendrup and colleagues (3) argued that this is not the case in high intensity exercise, as it was estimated that only 5-15g of exogenous carbohydrate are used during the first hour of exercise. This relatively small contribution to the total carbohydrate oxidation rate was thought too small to affect performance. Despite the lack of a clear metabolic rationale, both carbohydrates and fluids have been reported to enhance time trial performance independently (7). Below and his colleagues (1995) have already proved that providing both fluid and carbohydrate improved cycling time trial performance by approximately 6% compared to placebo. Additionally, the beneficial effect of fluid and carbohydrate ingestion during this type of exercise was reported to be additive. Although improvements from fluids were attributed to maintaining a higher cardiac output and attenuating the increases in core temperature and heart rate, carbohydrates did not find to influence neither core temperature nor heart rate. Furthermore, there were not found any significant effects of carbohydrate ingestion on blood glucose concentrations or carbohydrate oxidation rates. Thus, there was no clear metabolic explanation for the performance improvement by carbohydrates.

This unexplained phenomenon of a clear metabolic benefit when subjects ingest carbohydrate during short duration and intense exercise has led authors to hypothesize that carbohydrate may influence “central” or “non-metabolic” pathways during exercise. To investigate this potential central effect of carbohydrate on performance, authors have focused on the provision of glucose or fluid to the peripheral circulation by asking their subjects to simply mouth rinse the carbohydrate solution instead of ingesting it, during 1 hour running or cycling under laboratory conditions. These drinks according to researchers were well known commercial drinks (Lucozade, Gatorade, etc.) or non-flavored drinks (maltodextrin). Despite some differences in: the taste of drinks, the protocols used and the different type of exercise tested, the results were very positive, showing that having simply carbohydrates in the mouth, athletes managed to improve their performance as much as 3% (8,9). Moreover, one of the studies used functional magnetic resonance imaging to find out which regions of the brain are affected when rinsing these drinks during exercise. Researchers from this study demonstrated that the positive effects of carbohydrate mouth rinsing probably occurred due to receptors in the mouth that modulate central brain pathways associated with motivation (Figure 1). This consecutively impacts on the self-selection of exercise intensities during time trial performance. However, it is important to mention that the concentrations of glucose and maltodextrin solution used in these MRI studies have been more concentrated (18%) than the solutions used in studies that have shown a performance improvement (6-6.4%). Even so, these studies provide a significant insight into the brain response to the presence of carbohydrate in the mouth. 

However, a recent study at the University of Maastricht in the Netherlands (10) reported that performance benefits associated with carbohydrate mouth rinsing are not apparent following the consumption of a pre-exercise meal. What happened, they asked, if athletes ate breakfast before rinsing with carbohydrates; because no athlete under normal circumstances would stay “hungry” before participating in important events. Moreover, the positive effects of mouth rinsing sport drinks failed also to show evidence from a recent study conducted in Harokopio University (11), led by Dr. Arnaoutis & Dr. Kavouras. The researchers examined the role of «mouth rinse» in dehydrated athletes. The results demonstrated that ingestion of even a small amount of water increased exercise time in dehydrated subjects possibly through activation of pharyngeal receptors.

What’s more two more studies were published in 2011 demonstrating that mouth rinsing carbohydrate solutions do not affect maximum strength or strength endurance performance (12,13).

Generally, carbohydrate “mouth rinse” as a technique is still in early stage. In conclusion, a few studies have investigated the effects of carbohydrate mouth rinsing on endurance performance. Most of these studies have concluded that mouth rinsing with carbohydrate solutions during exercise of approximately 1 hour can have a beneficial effect when subjects are fasted. Moreover, no studies have reported any adverse effects on performance.

To date, for any athlete who is considering to try the above technique, keep in mind these tips below, which are based on the latest research summary:

1) Mouth rinsing sports drinks can improve the performance of one hour or less duration endurance exercise even when athletes do not swallow them.

2) If you are about to use this technique, you must follow it every 10 minutes.

3) The concentration of the drinks that have proved so far that they act positively are of 6% .

4) If you have eaten your meal 1-2 hours before your race, the technique of «mouth rinse» might not have the desired and expected effects.

5) Of course, spitting out a carb rinse won’t satisfy hunger, so endurance athletes are probably better off getting the added nutrition from eating or drinking during a race.

6) Carbohydrate mouth rinse is not beneficial for maximal sprint performance.

7) If you’re already dehydrated even before you start your race, consuming even small amounts of water during exercise is more beneficial than just rinsing it.

 No eating, no wrappers, no muscle cramps, just gargle and spit!

Find this article also at: http://sportsnutritioninsider.insidefitnessmag.com/4121/sport-drinks-wash-your-mouth-out-or-not

References:

1)      Coyle, E.F. and Montain, S.J. (1992a). Benefits of fluid replacement with carbohydrate during exercise. Medicine and Science in Sports and Exercise, 24:324–S330

2)      Tsintzas, K., Williams, C. (1998). Human muscle glycogen metabolism during exercise: effect of carbohydrate supplementation. Sports Med., 25:7-23

3)      Jeukendrup, A., Brouns, F., Wagenmakers, M., Saris, W. (1997). Carbohydrate-electrolyte feedings improve 1h time-trial cycling performance. Int Journ of Sports Med., 18:125-129

4)      Anantaraman, R., Carmines, A., Gaesser, G., Weltman, A. (1995). Effects of carbohydrate supplementation on performance during 1 hour of high-intensity exercise. Int J Sports Med. 16:461-465.

5)      Neufer, P., Costill, D., Flynn, M. et al. (1987). Improvements in exercise performance: effects of carbohydrate feedings and diet. J Appl Physiol., 62:983-988

6)      Rollo, I., Williams, C. (2009). Influence of ingesting a carbohydrate-electrolyte solution before and during 1-h running performance test. Int J Sport Nutr Exerc Metabol., 19:645-658

7)      Below, P., Mora-Rodriguez, R., Gonzalez-Alonso, J. et al. (1995). Fluid and carbohydrate ingestion independently improve performance during 1h of intense exercise. Med Sci Sports Exerc., 27:200-210

8)       Chambers, E., Bridge, M., Jones, D. (2009). Carbohydrate sensing in the human mouth: effects on exercise performance and brain activity. J Physiol., 578:1779-1794

9)      Pottier, A., Bouckaert, J., Gilis, W. Et al. (2010). Mouth rinse but not ingestion of a carbohydrate solution improves 1-h cycle time trial performance. Scand J Med Sci Sports, 20:105-111

10)   Beelen, M., Berghuis, J., Bonaparte, B., et al. (2009). Carbohydrate mouth rinsing in the fed state does not enhance time trial performance. Int J Sports Exerc Metab., 19:400-409

11)   Arnaoutis G. et al. (2011). Water ingestion improves performance compared with mouth rinse in dehydrated subjects.

12)   Chong et al. (2011). Effect of a carbohydrate mouth rinse on maximal sprint performance in competitive male cyclists.

13)   Painelliet al. (2011). The effect of carbohydrate mouth rinse on maximal strength and strength endurance.

Do it for your HEALTH afterall ;)

To cheat or not to cheat?

Κάνωντας μια μικρή αναδρομή στην ιστορία των cheat days ή cheat meals, πρέπει να αναφέρω ότι η ιδεά αυτή των «αμαρτωλών» γευμάτων αναπτύχθηκε γύρω στο 1999, ίσως και λίγο νωρίτερα. Φυσικά, τα cheat meals ανήκουν (κυρίως) στον κόσμο του body building , αλλά και στον πληθυσμό εκείνο που κάνει πολύ αυστηρή διατροφή. Στην αρχή η ιδέα του ελεύθερου γεύματος τρόμαζε τους περισσότερους..στην συνέχεια όμως, και μετά από επαληθευμένες μελέτες που έδειχναν ότι ενα έλευθερο γεύμα ανά τακτά χρονικά διαστήματα  μπορεί να επιταχύνει αντί να επιβραδύνει την απώλεια λίπους ( και αντίστοιχα βάρους), πολλοί άφησαν το φόβο πίσω τους..άλλοι ωστόσο επιμένουν πως τα cheat meals είναι μια κακή ιδέα για κάποιον που κάνει σοβαρή διατροφή. Ο κύριος σκοπός λοιπόν αυτού του άρθρου είναι να υπερασπιστεί τα αμαρτωλά γεύματα, και να αποδείξουμε ότι αμαρτίες στο φαγητό πρέπει να γίνονται, αλλά να γίνονται σωστά.

Για να ξεκινήσουμε από την αρχή – Γιατί να cheat;

Τα θεωρητικά οφέλη των cheat days είναι:

• Η αυξημένη παραγωγή ορμονών του θυρεοειδούς αδένα. Όταν βρίσκεστε σε ένα θερμιδικό έλλειμμα, τα υποσιτισμένα άτομα παράγουν λιγότερη T3 και T4 -και οι δύο σημαντικές ορμόνες του θυρεοειδούς που παίζουν ρόλο στη ρύθμιση του μεταβολισμού. Μια αμαρτωλή ημερα λοιπόν μπορεί να χρησιμοποιείται εν μέρει για την αύξηση αυτών των ορμονών.
• Η αύξηση μεταβολισμού για όλο το 24ωρο. Έρευνες όπως αυτή  έχουν δείξει πως το πλεόνασμα θερμίδων από μία cheat ή αλλιώς overfeeding day αναγκάζει το σώμα να  κάνει υπέρ-ρύθμιση και να αυξάνει το βασικό μεταβολικό ρυθμό (BMR). Η αύξηση αυτή κυμάινεται από 3-10%. 3% αύξηση παρουσιάζουν τα άτομα με αρκετό σωματικό λίπος ενώ το 10% αγγίζουν άτομα με χαμηλό ποσοστό λίπους. Ωστόσο αυτό δεν σημαίνει πως η υπερκατανάλωση πρέπει να γίνει συνήθεια επειδή καίμε λίγες παραπάνω θερμίδες…
• Η αύξηση των επιπέδων της ορμόνης λεπτίνης. Για όσους δεν γνωρίζουν, η λεπτίνη είναι μια πρωτεΐνη που παράγεται στα λιποκύτταρα από το γονίδιο «ob» (obesity gene) και μέσω ειδικών υποδοχέων που βρίσκονται στον υποθάλαμο, καθορίζει την όρεξη, τον ρυθμό μεταβολισμού του σώματος και το επίπεδο σωματικής δραστηριότητας. Τα επίπεδα όμως  λεπτίνης μειώνονται σε θερμιδικό έλλειμμα και αυτό αποτελεί πρόβλημα για τους dieters. Έτσι, θεωρήθηκε και επιβεβαιώθηκε με την παρακάτω έρευνα  ότι ένα χτύπημα στην περιοδική έκκριση λεπτίνης που προέρχεται από ένα cheat meal θα επιφέρει τα παραπάνω οφέλη.

Αυτά είναι φυσιολογικά και μεταβολικά οφέλη των αμαρτωλών ημερών. Φυσικά, υπάρχει και το ψυχολογικό πλεονέκτημα. “Τρώτε ό,τι θέλετε και παρ’όλα αυτά το βάρος σας δεν θα επηρεαστεί”. Πόσο πολύ μπορεί να ευχαριστεί κάποιον που κάνει αυστηρή διατροφή αυτή και μόνο η ιδέα;

Το πρόβλημα με τα cheat days

Oυσιαστικά, όπως ανέφερα παραπάνω, τα πλεονεκτήματα των cheat meals επέρχονται λόγω της μειωμένης λεπτίνης που παράγεται στα άτομα αυτά που προσέχουν αρκετά τη διατροφή τους και βρίσκονται σε θερμιδικό έλλειμα. Το πρόβλημα έιναι όμως ότι οι περισσότεροι που δοκιμάζουν να ακολουθήσουν περιοδικά cheat meals είναι συνήθως αυτοί που δεν έχουν μειωμένα αποθέματα λεπτίνης, δηλαδή δεν βρίσκονται σε θερμιδικό έλλειμα, οπότε και αποτέλεσμα δεν υπάρχει.

Ένα δευτερο πρόβλημα με τα cheat meals, προέρχεται από κάποιες άλλες πηγές και αναφέρουν πως τα γευματα αυτα μπορεί να γίνουν εθιστικά…Η άποψη αυτή στηρίζεται κάπως έτσι:«Λέγοντας σε κάποιον που κάνει δίαιτα να έχει ένα cheat meal την εβδομάδα είναι σα να λες σε έναν αλκοολικό ότι η κατανάλωση ποτού μια φορά την εβδομάδα είναι επιτρεπτή.» Κάτι τέτοιο δεν ισχύει. Όπως δεν ισχύει και το ότι καποιος που τρώει μια φορά την εβδομάδα junk food είναι εθισμενος σε αυτό, γιατί αλλιώς θα έπρεπε και όποιος πίνει αλκοόλ να είναι αλκοολικός κοκ…

Μια άλλη υπόθεση είναι ότι τα γευματα αυτά διαιωνίζουν τον εθισμό. Για να ισχύει αυτό όμως θα πρέπει να ισχύουν τα παραπάνω, πρέπει να δεχτούμε δηλαδή ότι όποιος έχει τέτοια γευματα στο εβδομαδιαίο πρόγραμμα του είναι εθισμένος, κατι που αναλύθηκε πιο πάνω. Δεν λέω, υπάρχουν και άτομα που έχουν σοβαρά προβλήματα με το φαγητό και ναι τότε ίσως για αυτούς να μην είναι και ότι πιο σοφό ένα τέτοιο πρόγραμμα διατροφής. Όμως εξακολουθούν να αποτελούν την εξαίρεση και όχι τον κανόνα.

Πως να cheatαρετε;

Λοπόν σας έπεισα και αποφασίσατε να cheatαρετε. Πολύ καλά! Ας δούμε πως μπορείτε να το κάνετε σωστά. Εδώ πρέπει να σκεφτείτε, αν δεν βρίσκεστε σε πολύ αυστηρή υποθερμιδική δίαιτα, δεν χρειάζεται να cheatαρετε πολύ συχνά. Όσο πιο πολύ περιορίζετε τις θερμίδες σας, τόσο γρηγορότερα τα επίπεδα λεπτίνης “θα πέσουν” και τόσο πιο πολύ θα επωφεληθείτε από μια cheat day! Για να μιλησουμε και με αριθμούς, αν βρίσκεστε στις -700 με 800 θερμίδες τότε μια ελεύθερη μερα την εβδομάδα επιβάλλεται. Αν όχι, καλύτερα να περιοριστείτε σε 1 με 2 φορές το μήνα και σε cheat meal και όχι ημέρα. Στο πόσο συχνα θα αμαρτήσετε παίζει ρόλο και πόσο «στεγνός/η» είστε. Όσο περισσότερο τόσο πιο συχνό cheat. Μιλώντας με αριθμούς, εάν είστε 10% ή πιο κάτω σε ποσοστό σωματικού λίπους, μπορείτε να αμαρτήσετε μια φορά κάθε 5-7 ημέρες. Αν είστε 10-12%, περίπου κάθε 7-9 ημέρες. Εάν είστε πάνω από 12%, μπορείτε μια φορά κάθε δύο εβδομάδες. Το βασικότερο από όλα σε μια ελεύθερη μερα είναι να μην ωθήσεται τον οργανισμό σας πέρα από το σημείο του κορεσμού. Τρώτε ό,τι θέλετε, ναι, αλλά σταματήστε να τρώτε όταν αισθάνεστε όμορφα και πλήρης J

Fat burners: Ποια δουλεύουν και ποια μας δουλεύουν…

Η υπερκατανάλωση τροφής εξακολουθεί να είναι ένα από τα σημαντικότερα προβλήματα υγείας του 21ου αιώνα. Στον κόσμο του Fitness, διαιτολόγοι αλλά και διάφοροι άλλοι Fitness related professionals, δεχoμαστε συχνά ερωτήσεις όπως: “Ποιες ασκήσεις καίνε περισσότερο λίπος;”, “ποια είναι τα πιο αποτελεσματικά fat burners;”Πρέπει να κόψω το λίπος από τη διατροφή μου για να αδυνατίσω;” κ.ο.κ. Παρακάτω θα προσπαθήσω να απαντήσω σε μερικές από τις ερωτήσεις που οι περισσότεροι από εσάς έχετε κάποτε αναρωτηθεί ή ακόμα αναρωτιέστε.
Μπορώ να πετύχω μείωση του βάρους μου αν καταναλώνω γεύματα χαμηλά σε λιπαρά;

Όχι. Αν και το λίπος έχει τις περισσότερες θερμίδες ανά γραμμάριο (9 θερμίδες/γρ) σε σύγκριση με τους υδατάνθρακες και την πρωτεΐνη (4 θερμίδες/γρ), η υπερκατανάλωση θερμίδων, ανεξάρτητα από τα μακροσυστατικά προέλευσης, σε συνδυασμό με την χαμηλή σωματική άσκηση, είναι η αιτία για την αύξηση του σωματικού βάρους. Ακόμα και αν το λίπος υστερεί στην διατροφή, εξακολουθούν να υπάρχουν τρόποι όπου οι εξτρα θερμίδες θα εισέλθουν στο σώμα σας και θα αυξήσουν το βάρος σας. Ένα ενδιαφέρον πείραμα του Βray et al. (2012) που εξέτασε την ισότιμη υπερκατανάλωση θερμίδων αλλά με βάση διαφορετικά ποσοστά πρωτεϊνών (μικρή, μεσαία και μεγάλη κατανάλωση αυτών) διαπίστωσε πως η αύξηση του σωματικού λίπους ήταν ίδια και στα 3 γκρουπ, ανεξάρτητα από τα ποσοστά πρωτεΐνης που αυτοί κατανάλωναν.

Είναι η L-Carnitine ένα αποτελεσματικό συμπλήρωμα για την καύση λίπους και την αύξηση της μυικής μάζας;

Δεν ξέρουμε με σιγουριά. Η L-καρνιτίνη υπάρχει σε μεγάλες ποσότητες στο κρέας και ήταν ένα συμπλήρωμα που προκαλούσε μεγάλο ενδιαφέρον για δύο δεκαετίες. Η πρωταρχική λειτουργία της L-καρνιτίνης είναι να μεταφέρει μακράς αλύσου λιπαρά οξέα σε όλη την εσωτερική μεμβράνη των κυττάρων των μυών του (ATP σύνθεση οργανίδιο), όπου τα λιπαρά οξέα αναλύονται και διασπώνται περαιτέρω. Ορισμένοι πιστεύουν ότι η τακτική κατανάλωση της L-καρνιτίνης ως συμπλήρωμα θα βοηθήσει στην απώλεια βάρους, με την αύξηση της συγκέντρωσης του κυττάρου της καρνιτίνης, αυξάνοντας έτσι την μεταφορά των λιπαρών οξέων για την ενίσχυση του μεταβολισμού του λίπους. Δυστυχώς όμως, δεν υπάρχουν αξιόπιστα επιστημονικά στοιχεία που να υποστηρίζουν αυτό τον ισχυρισμό.

·Μπορεί η καφείνη ως συμπλήρωμα να αυξήσει τις μεταβολικές καύσεις κατά την διάρκεια της άσκησης αλλά και κατά την διάρκεια ηρεμίας;

Ναι (και όχι). Η καφεΐνη έχει αποδειχθεί ότι αυξάνει την δραστηριότητα του συμπαθητικού νευρικού συστήματος, αποδεσμεύοντας έτσι τα λιπαρά οξέα από τον λιπώδη ιστό αλλά και από αποθήκες ενδομυϊκού ιστού, με αποτέλεσμα την αυξημένη χρήση αυτών. Η καφεΐνη έχει επίσης συσχετισθεί με μεταβολικές διαδικασίες που ενισχύουν την κατανομή λίπους. Αν και οι επιδράσεις της καφεΐνης φαίνεται να ενισχύουν τον μεταβολισμό σε κατάσταση ηρεμίας και κατά τη διάρκεια άσκησης χαμηλής έντασης (σε μικρότερο βαθμό κατά τη διάρκεια της μέτριας έως υψηλής έντασης άσκηση), οι Jeukendrup & Randell επισημαίνουν πως οι επιπτώσεις εξακολουθούν να είναι μικρές. Εξ’ άλλου αν όντως η καφεΐνη ήταν τόσο ευεργετική τότε το πρόβλημα του βάρους θα είχε λυθεί..

Μπορεί το συζευγμένο λινολεικό οξύ (CLA) να ενισχύσει την απώλεια λίπους;

Καταρχάς, το CLA είναι μια ουσία που ανακαλύφτηκε μόλις το 1987 από τον Dr. Michael Pariza, επιστήμονα του Ινστιτούτου Διατροφικής Έρευνας, του Πανεπιστημίου του Wisconsin, στις Ην. Πολιτείες και βρίσκεται κυρίως στο γάλα και στο κρέας. Χαρακτηριστικά να αναφέρουμε ότι ανακαλύφτηκε μέσα από μια έρευνα σε ποντίκια, με την οποία έδειξε ότι η ύπαρξη αυτής της ουσίας που ονομάστηκε CLA-συζευγμένο λινολεϊκό οξύ, εμπόδισε την εμφάνιση καρκινικού όγκου στα πειραματόζωα, ενώ ο ίδιος επιστήμονας σε πειράματα με κουνέλια έδειξε την θετική επίδραση του CLA στη μείωση της αθηροσκλήρωσης. Το συζευγμένο λινολεϊκό οξύ (CLA) προωθείται ως παράγοντας κατά της παχυσαρκίας. Υπάρχουν ενδείξεις ότι αυξάνει την κατανάλωση ενέργειας, την οξείδωση των λιπών, ενώ παράλληλα ίσως μειώνει την όρεξη…σε ποντίκια! Πιο πρόσφατες έρευνες έχουν δείξει ότι συμπλήρωμα των 3γρ CLA ημερησίως θα οδηγήσει σε πολύ μικρή απώλεια λίπους, σχεδόν ασήμαντη.

Μπορεί η ταυρίνη να αυξήσει την καύση λίπους;

Ενδεχομένως. Τελευταία προωθούνται ευρέως για την απώλεια βάρους. Η ταυρίνη είναι ένα αμινοξύ που είναι απαραίτητο για την ομαλή λειτουργία των σκελετικών μυών. Υπάρχει μελέτη στην οποία έχει βρεθεί συσχέτιση μεταξύ ταυρίνης και αύξησης της οξείδωσης των λιπών κατά την άσκηση. Περαιτέρω έρευνες όμως είναι απαραίτητες για να καθοριστεί πλήρως η αποτελεσματικότητα της ταυρίνης για τα προγράμματα διαχείρισης βάρους καθώς και οι επιπτώσεις κατανάλωσης αυτής δεν έχουν μελετηθεί πλήρως.

Συμπέρασμα
Όλα αυτά τα συμπληρώματα έχουν γίνει ήδη μεγάλη εμπορική επιτυχία και θα συνεχίσουν έτσι. “Ενδεχομένως” μερικά από αυτά να λειτουργήσουν. Άλλα πάλι όχι. Όμως, σε γενικές γραμμές, δεν δίνουν λύση στην αιτία του προβλήματος, που είναι η υπερκατανάλωση τροφής, δίνoυν απλώς μία λύση στο σύμπτωμα. Με άλλα λόγια ίσως είναι η απάντηση σε μία λάθος ερώτηση.

Πηγές:

Jeukendrup & Randell 2011, Fat burners: nutrition supplements that increase fat metabolism (?).

H αλόγιστη χρήση των πολυβιταμινούχων στους αθλητές.Πως φτάσαμε ως εκεί;

Στις μέρες μας  είναι συχνό φαινόμενο οι  αθλητές να καταναλώνουν πολυβιταμινούχα συμπληρώματα. Όντως οι ανάγκες σε βιταμίνες σε μερικά «υπέρ»αθλήματα είναι τόσο μεγάλες σε βιταμίνες και ιχνοστοιχεία που ίσως ακόμα και μια ισορροπημένη διατροφή δεν μπορεί να προσφέρει την απαιτούμενη ποσότητα. Ωστόσο, πριν φτάσουμε στην χρήση πολυβιταμινούχων, ένα μεγάλο λάθος που παρατηρείται στο χώρο του αθλητισμού είναι η αποδοκιμασία της διατροφής ως πηγή βιταμινών και η καταφυγή κατευθείαν σε τέτοια συμπληρώματα. Αθλητές όλων των επιπέδων πρέπει πρώτα λοιπόν να ξέρουν πως να ακολουθήσουν ένα πρόγραμμα διατροφής προσαρμοσμένο στις ανάγκες τους και μετά να αναρωτηθούν για τη χρήση συμπληρωμάτων βιταμινών. Δεν είναι λίγες οι φορές εξάλλου που αθλητές Ironman ή μαραθωνοδρόμοι έχουν βρεθεί να καταναλώνουν υπερβολικές ποσότητες βιταμινών.

Το θέμα λοιπόν των συμπληρωμάτων έχει πάρει μεγάλες διαστάσεις. Ας δούμε μερικά επιδημιολογικά αποτελέσματα. Σύμφωνα με έρευνες, τα 2/3 των αθλητών σήμερα καταναλώνουν συμπληρώματα βιταμινών. Μαζί με τα βιταμινούχα συμπληρώματα, ευρεία σε χρήση είναι τα αθλητικά ποτά και οι αθλητικές μπάρες. Το ενδιαφέρον παρουσιάζεται όταν πολλοί από τους αθλητές που καταναλώνουν τέτοιου είδους συμπληρώματα, έχουν άγνοια του τι ακριβώς καταναλώνουν και γιατί. Συγκεκριμένα, σε μία πρόσφατη γενικά έρευνα, οι περισσότεροι αθλητές βρέθηκε να θεωρούν ότι τα αθλητικά ποτά και οι αθλητικές μπάρες δεν είναι συμπληρώματα,  ότι οι βιταμίνες και τα μέταλλα είναι πηγή ενέργειας, ότι η καφεΐνη και τα καφεινούχα προϊόντα είναι επίσης πηγή ενέργειας και ότι το φαγητό δεν μπορεί να «δώσει» τόσα όσα ένα συμπλήρωμα μπορεί. Τα αποτελέσματα αυτά παρουσιάζονται και σε άλλες έρευνες στην Αυστραλία, όπου το 40% υψηλού επιπέδου αθλητών της Αυστραλίας δεν μπορούσε να αναγνωρίσει τα συστατικά του συμπληρώματος που κατανάλωνε, 45% δεν ήξερε τι παρενέργειες μπορούσε να προκαλέσει το συμπλήρωμα που κατανάλωνε, 47% δεν γνώριζε πως ακριβώς το συμπλήρωμα μπορούσε να τον βοηθήσει στην βελτίωση της απόδοσης ενώ σχεδόν το 50% δεν ήξερε την ακριβής δοσολογία του συμπληρώματος!

Είναι ήδη γνωστό πως οι περισσότεροι αθλητές στις μέρες μας δεν προμηθεύονται συμβουλές από κάποιον ειδικό και ίσως γι’ αυτό έχουμε τα παραπάνω αποτελέσματα. Είναι σίγουρο πως υπάρχουν πολλοί άνθρωποι εκεί έξω οι οποίοι θέλουν να σας συμβουλέψουν διατροφικά, αλλά οι περισσότεροι συνήθως δεν είναι ειδικευμένοι σε αυτόν τον τομέα και δεν γνωρίζουν για τι ακριβώς μιλάνε. Το χειρότερο είναι όταν οι κατασκευαστές ενός προϊόντος δίνουν οδηγίες στους αθλητές για το πόσο πρέπει να καταναλώνουν και πότε. Ίσως λοιπόν ένα μερίδιο ευθύνης να φέρουν οι κατασκευαστές και οι φίλοι που σας προμηθεύουν με συμβουλές ενώ στην ουσία οι γνώσεις τους είναι ελλιπείς. Μερίδιο όμως φέρουν και οι ίδιοι οι αθλητές που κατά τη κρίση τους έχουν πάρει τις σωστές συμβουλές.

Ωστόσο, δεν φταίνε μόνο οι αθλητές. Υπάρχουν και καλές έρευνες  οι οποίες απλά έχουν παρερμηνευθεί. Για παράδειγμα, το 2008 στο Πανεπιστήμιο του Birmingham με επικεφαλή τον καθηγητή Asker Jeukendrup, δημοσιεύθηκε η πρώτη έρευνα που έδειχνε τα πλεονεκτήματα της χρήσης αθλητικών ποτών που περιείχαν μια μείξη γλυκόζης και φρουκτόζης (αντί του συνηθισμένου μόνο με γλυκόζη) κατά τη διάρκεια της άσκησης. Σε αυτή την έρευνα οι αθλητές έπιναν 60γρ γλυκόζη συν 30γρ φρουκτόζη ανά ώρα (αναλογία 2:1). Έτσι λοιπόν πολλοί κατασκευαστές άρχισαν να κατασκευάζουν και να προωθούν αθλητικά ποτά με αναλογία γλυκόζης-φρουκτόζης 2:1 ως το κλειδί για την επιτυχία στα αγωνίσματα αντοχής. Στην ουσία όμως, η έρευνα αυτή αφορούσε αθλητές που κατανάλωναν περισσότερα από 60γρ/ώρα υδατανθράκων, ενώ δεν είχε βρεθεί κάποιο όφελος όταν οι αθλητές κατανάλωναν 45γρ/ώρα ή λιγότερα . Με άλλα λόγια, αυτό που είχε σημασία ήταν η συνολική ποσότητα γλυκόζης και φρουκτόζης που καταναλωνόταν κατά τη διάρκεια της άσκησης και όχι η αναλογία 2:1, και αυτό μπορούσε να γίνει από διάφορες πηγές, ακόμα και από κανονικές τροφές και όχι μόνο από αθλητικά ποτά, σύμφωνα με τους ερευνητές.

Πως μπορεί ένα συμπλήρωμα βιταμινών να με βλάψει;

Ενδεικτικά θα αναφερθούμε σε γενικές επιπτώσεις που έχουν παρατηρηθεί προηγουμένως από υπερβολικές δόσεις (>DRI) συγκεκριμένων βιταμινών. Γυρίζοντας λοιπόν στις βιταμίνες και σε ότι αφορά τις υδατοδιαλυτές, στις περισσότερες περιπτώσεις δεν υπάρχει κίνδυνος επειδή αποβάλλονται εύκολα με τα ούρα. Ωστόσο ενδεικτικά να πούμε ότι μεγάλες δόσεις  Β6 έχουν τοξικές επιδράσεις στον οργανισμό. Συγκεκριμένα, υπερδόσεις αυτής μπορεί να προκαλέσουν προβλήματα στο συκώτι και νευρολογικές διαταραχές. Ακόμα και η υδατοδιαλυτή βιταμίνη C, η οποία θεωρείται ότι σε φυσιολογικές δόσεις δρα ως εκκαθαριστής ελευθέρων ριζών Ο2, σε ορισμένες περιπτώσεις, σε μεγάλες δόσεις προάγει την οξείδωση και αυξάνει τα επίπεδα ουρικού οξέος, προκαλώντας προβλήματα σε άτομα με τέτοια προδιάθεση. Επίσης, σε μία μελέτη από τον Ristaw και τους συνεργάτες του που έγινε το 2009 βρέθηκε ότι η παρουσία μεγάλης ποσότητας βιταμίνης C αλλά και Ε, απέτρεψε τη βελτίωση της ευαισθησίας στην ινσουλίνη, ένα από τα κύρια κέρδη της γυμναστικής. Τα πράγματα είναι πιο σημαντικά για τις λιποδιαλυτές βιταμίνες λόγω του ότι η αποβολή τους είναι αργή και μεγάλο μέρος τους συγκρατείται στο ήπαρ και το λιπώδη ιστό. Μεγαδόσεις βιταμίνης Α μπορεί να προκαλέσουν αδυναμία, ναυτία, πόνο στις αρθρώσεις ή ηπατική βλάβη.  Αλόγιστη επίσης υπέρμετρη φόρτιση του οργανισμού με μεγάλες ποσότητες Fe(σιδήρου) χωρίς την ύπαρξη αναιμίας, δημιουργεί μια σωρεία προβλημάτων, όπως καταστροφή ενδοκρινών αδένων, κίρρωση του ήπατος και γαστρεντερικές διαταραχές.

Συνοπτικά

Οι δυσκολίες στην εκπαίδευση των αθλητών γύρω από τη χρήση συμπληρωμάτων έχει πολλές δυσκολίες. Και αυτό γιατί δεν μπορούμε να αγνοήσουμε την πλύση εγκεφάλου που δέχονται μικροί και μεγάλοι αθλητές γύρω από το θέμα των βιταμινών και την απροσδιόριστη “θαυματουργή” χρήση τους.  Ωστόσο, κανείς δεν είπε ότι τα συμπληρώματα βιταμινών είναι  άχρηστα. Αυτό που είναι άχρηστο είναι η αλόγιστη χρήση τους, όταν δεν ξέρουμε για τι συμπλήρωμα μιλάμε, για πιο άθλημα μιλάμε, τι δόση πρέπει να καταναλώσουμε και το πλαίσιο διατροφής του κάθε ατόμου. Παραδείγματος χάριν, η χρήση πολυβιταμινούχων φαίνεται να είναι απαραίτητη σε άτομα που ακολουθούν διάσημες υποθερμιδικές δίαιτες όπως φάνηκε στην προκειμένη έρευνα. Συνεπώς κάθε άνθρωπος είναι διαφορετικός και έχει τις δικές του ανάγκες. Το μόνο που έχετε να κάνετε είναι να συμβουλευτείτε τον ειδικό σας

Πηγές:

Ristaw, et al.  2009. Antioxidants prevent health-promoting effects of physical exercise in humans. Proceedings of the National Academy of the National Academy of Sciences of the United States of America

Knez, 2010. The Prevalence of Vitamin Suppiementation in Ultraendurance Triathietes. International Journal of Sport Nutrition and Exercise Metabolism, 20, 507-514

 Calton, 2010. Prevalence of micronutrient deficiency in popular diet plans. J. International Society of Sports Nutrition,10, 7-24

Jeukendrup & Moseley, 2008. Multiple transportable carbohydrates enhance gastric emptying and fluid delivery. Scandinavian journal of medicine &amp; science in sports

 McArdle, Katch & Katch, 2005, Sports and Exercise Nutrition