Archive | June, 2011

PhD and RD talks Sports Nutrition

21 Jun


SNI: Which protein is best (if any) for promoting gains in skeletal muscle mass? Or are all proteins created equal?

Dr. Lowery: Well, there are plenty of very good protein sources, from meats to eggs to dairy. If I had to pick, I’d suggest whey or casein. Research varies somewhat as to which is superior for different age groups or times of the day but the dairy proteins seem to have real partitioning effects (preferentially helping one build muscle mass.) For me, it’s whey or a whey-casein blend pre- and post-workout, then casein like cottage cheese or a whey-casein supplement at bed time. I like whey-casein blends because of their versatility; the whey remains fast acting, raising circulating amino acids and protein synthesis while the casein portion clots in the gut for a more steady, ‘anti-catabolic’ effect. I do think eggs and moderately lean meats are a close second, though, due to other nutrients they provide.

There are several ways of determining protein quality, from biological value to protein effeciciency ratio, to the PDCAAS (protein digestibility-corrected amino acid score). If one considers the PDCAAS the ‘gold standard’ as many do, he can see that several proteins score very highly. Still, I try not to get bogged down by these ratings and consider the whole food and all it entails. For example, meats are solids and give one something tasty to chew on and enjoy, which is important for dietary compliance.

SNI:  Is there a finite amount of protein one should consume per meal?

Dr. Lowery: Fairly recent research on egg protein suggests the number is 20 grams per feeding – about three eggs or one scoop of protein powder. That dose could be different for other protein types. It’s not so much a question of ‘How much can I digest at one time?’ as many persons wonder, but rather the limitation stems from one’s internal anabolic environment. Once those amino acids enter the blood, there’s a certain requirement for anabolic hormones for example. Any amino acids not used for protein synthesis will just be stripped of their nitrogen and oxidized (burned) or used to make new blood sugar. Some dietitians will tell clients that excess protein becomes body fat but that’s mostly just a plausibility argument based on protein’s 4 kcal per gram. Ask yourself this; How many persons do you know who became obese eating skinless chicken breasts, egg whites and low-fat cottage cheese?

Also, some persons over-conclude that at a 20g ‘ceiling’, even with six meals per day, one would only ever need 120g of protein daily. Although this is a good number for many healthy persons, I personally think athletes with particular goals such as fat loss or recomposing their bodies, could consume more. And for those who feel ample protein intakes are unhealthy (which they are not), consider this; one has to eat *something* when he’s hungry! Protein foods are rich in other nutrients, satiating (filling, satisfying) and have a much higher thermic effect of food (TEF) than carbohydrates and fats.

SNI: What is your opinion on soy protein?

Dr. Lowery: I don’t think soy is a bad protein. Its PDCAAS is very high. Still, I remain a little wary that soy foods bring with them phytoestrogens that are still being studied as far as all of their health effects (breast cancer risk, etc.). Plus, after it’s track record of blunders, the agro-food industry doesn’t instill confidence in me. From this industry there is a LOT of promotion of soy – for example through sponsorship of professional dietetic events – and I sometimes worry about bias in the positive messages that get promulgated. I think that, for those who may be concerned but strive for dietary variety, going meatless once per week (with soy foods and others) can be a nice, moderate policy.

SNI: Why does the myth that high protein diets harm kidney function seem to persist? How do you combat such a myth?

Dr. Lowery: This is controversial but I sometimes think that there are longstanding professional issues of reputation, money and politics – as well as dogma – that tend to keep concerns over ample protein diets around. As Upton Sinclair once said; ”It is difficult to get a man to understand something when his salary depends on his not understanding it.’ For example, for decades dietitians have witheld protein from patients with kidney disease (which is itself less conclusive in the literature than one might think) and this has spilled over erroneously into recommendations for healthy populations. If I were a renal dietitian getting insurance company or government reimbursement for witholding protein from patients, I might not be especially critical of the practice. Or if my lauded and profitable nutrition care of overzealous athletes involved protein dissuasion, I might embrace what my colleagues believe or what introductory textbooks have told me rather than going outside my group to the primary literaure for a current, balanced view. Admitting I’ve been wrong all this time would be rough. I’m not saying this narrow-mindedness always happens but I am saying that my conversations with scientists tend to be very different in tone from the conversations I have with clinicians on the issue. I think there can be a disjoin or lag between the two groups. Change takes time and requires impetus. Maybe the nation’s obesity epidemic will serve as such an impetus to give (satiating, metabolism boosting, muscle-preserving) higher-protein diets a fairer shake.

In summary, consider this: Many clinicians and health educators are busy, are well paid for practicing the status quo, see the world in a bit more black-and-white way than do scientists, and move in fairly insular circles. They thus tend to stick to their guns. Unfortunately, those ‘guns’ can be almost silly when it comes to protein, as we catalogued in a 2009 ISSN paper. This documenting of what’s being taught – and comparing it to the actual (lack of) evidence thereon – is one way to combat the high protein myth.

SNI: What is the difference between a dietitian and a sports nutritionist?

Dr. Lowery: This depends on the state. Nutrition and dietetics licensure differs across the country, with some states requiring the Registered Dietitian credential (with follow-up state licensure) to give nutritional advice or to use titles like Nutritionist. Some states do not require this. There is also the more specific sports dietetics certificate but this is more optional, depending on one’s educational background. As a dietitian with a Masters in Nutrition and three degrees in Exercise Physiology including a doctorate, I for example would feel a bit silly going back to get this certificate in order to justify my involvement in exercise and sports nutrition.

I personally am glad that certificates from any particular group are not legal requisites. I do not feel that study for a four-hour exam on a Saturday is equivalent to a four-year degree (or more) in the field of interest. The university degree should obviously carry more weight. Certificates simply help document one’s expertise if he or she wants to do so. A sports nutrition certificate, from whichever group, is simply a way to prove one has successfully met the competency requirements in the included topics. It helps other professionals and consumers judge one’s expertise. I feel that certificates in a free market, with healthy competition, help consumers overall by presenting options and preventing monopoly by one potentially opinionated or insular group. Having said that, it is important for the public to have some idea which groups and which certificates are most rigorous and most legitimate.

What Do You Value

20 Jun

I was listening to a discussion between two strength coaches the other day talking about the excuses they hear from people regarding exercise and nutrition, and it got me thinking.

What are your priorities in life and where do exercise and nutrition fit in all that?

One of the most often used excuses is, “I don’t have time”.  But this raises an interesting counter-question in my mind: don’t have time for what?  Everyone is dealt the same 24 hours in the day, and it is really a matter of how your prioritize those hours.  Some will tell you that family comes first, or that work must be a priority, and those things are ok.

But everyone also has to eat.  Why not make those meals good ones?  Food has taken on almost mythical properties in our culture, purported to assist in any and all that ails you: Ice cream heals a broken heart, wings and beer make watching the game more fun, vegetables cure cancer, rice and sprite calm an upset stomach, chocolates and oysters help to set the mood.  I think you get my point.

In reality though, food’s primary role is to fuel your body and mind from day to day.  That is not to say that there aren’t better (and worse options).  My approach to food has always been to eat foods that are either of the earth or on the earth, and as close to their natural state as possible.  Examples you ask…

Vegetables, fruits, tubers are all OF the earth.  Animals, of course, are ON the earth.

The question I used to get from the high schoolers I worked with was about the natural-state clause: Grilled chicken thighs with the skin on are much closer to nature than those deep-fried and breaded wings you just gobbled down.

So what foods are the better ones?  In a recent nutrition seminar I attended, I heard the most succinct qualifier for which foods one should eat – those that move you closer to optimal health.  While there are health claims made about almost any food under the sun (twinkie diet anyone?) there are obviously more nutritious and healthful foods out there; there are foods that while superficially benign, are actually responsible for all sorts of negative consequences under the surface.

Shouldn’t we all be trying to provide our bodies (and brains) with the best foods we can?  Maybe that means forgoing the pizza because it’s quick, and instead spending the extra time to grill the steaks and veggies you have sitting in the fridge?  It might take a little bit of planning on the front end, but the benefits will be much more long-lasting (UC-Berkeley journalism professor and food writer, Michael Pollan, has spoken at length about the hidden costs – medical, environmental, etc. – of quick processed foods, and that spending more time and money preparing healthy foods will actually be cheaper in the long run).

So I bring you back to the earlier question: where do you place your priorities?  I know for myself, a good meal is only a great meal if it actually makes me healthier for eating it.

It’s Getting Real in the Whole Foods Parking Log

20 Jun

Hilarious rap about the life of a conscientious shopper, courtesy of Civil Eats

Don’t Choke! Learn How To Speak Anywhere and To Anyone

15 Jun

When: Tonight @ 6:30pm to 8:30pm

Where: FIT

Presented By: Lauren Velasco

Lauren Velasco was raised locally – a graduate of Gunn High School and Stanford University. Her undergraduate years were spent at Bates College in Maine, where she competed on the national and international speech and debate circuits, and graduated with Highest Honors in Rhetoric. She and her debate partner were ranked #4 in the United States, and were selected to compete in three North American and two World Debate Championships. Lauren also competed in the World Individual Speech Championship and participated in the World Summit on Women in Debate. She has independently produced five documentary films and videos, three of which have been shown on television and featured in local, national and international film festivals. While a Communication graduate student at Stanford, she served as Interim Director of the Women’s Center and taught Public Speaking in Stanford’s Technical Communication Program. Also a licensed disc jockey, Lauren has been a full-time member of the Communication Studies faculty at Foothill College since 2000. She is the founder and coach of Foothill’s award-winning Speech and Debate Team, and offers private workshops and tutoring, as time permits.

Interview with Dr. Volek on Low-Carb Diets

15 Jun

Dr. Volek: First let me thank you for the opportunity to discuss low carbohydrate diets. This has been a focus of my research for nearly 15 years. Low carbohydrate diets are commonly practiced but seldom taught. As a result, whether by design or neglect, mainstream medicine has either ignored or relegated this powerful tool to casual use. Together with Dr. Steve Phinney, a physician-scientist with extensive knowledge of low carbohydrate diets, we recently published a definitive book on the topic. In The Art and Science of Low Carbohydrate Living, we provide an unabridged and in-depth perspective on this controversial and often misunderstood topic.

SNI:Define what a ‘low carbohydrate’ diet is? That is, at what % carbohydrate does a diet become low? Also, is there a difference between a ketogenic diet and a low-carb diet?

Dr. Volek: Defining a low carbohydrate diet could be done in two ways:

What a Person Perceives: A low carbohydrate diet is one that limits carb intake to a level that results in resolution of all signs of carbohydrate intolerance. What’s carbohydrate intolerance? Like other food intolerances (lactose, gluten) carbohydrate intolerance is characterized by an undesirable response to carbohydrate. Since the inability to properly metabolize dietary carbohydrate is the direct result when insulin action is impaired, insulin resistance is synonymous with carbohydrate intolerance. In other words a low carbohydrate diet is one that improves the features of insulin resistance or metabolic syndrome. People vary widely in their level of carbohydrate intolerance. One person with early signs of metabolic syndrome may only need to restrict carbs to under 80 grams per day to lose weight and keep it off whereas another person may need to stay under 40 grams per day to put a frank case of type-2 diabetes into remission.

What Happens Metabolically: In this case, a low carbohydrate is defined by the level below which there is a fundamental shift away from glucose as a primary fuel that allows most of your daily energy needs to be met by fat, either directly as fatty acids or indirectly by ketone bodies made from fat. This process begins for most people when total carbohydrate is restricted to less than 60 grams per day. After a few weeks at this level, ketones begin to rise ~10 fold in plasma, resulting in a commensurate reduced need for glucose. Further restriction of carbs causes greater ketone production up to a point. The keto-adaptation that occurs gives human metabolism the flexibility to deal with famine or major shifts in available dietary fuels. This should not be confused with ‘diabetic ketoacidosis’ which is a completely different metabolic state.

SNI: What’s the data show regarding the effects of low carbohydrate diets on cardiovascular health?

Dr. Volek: How low fat and low carbohydrate diets impact risk for heart disease is one of the great nutrition debates of all time. For more than 3 decades, mainstream medicine and nutrition policy has been based on the diet-heart hypothesis. The syllogistic logic of the diet heart hypothesis is that lowering fat intake (specifically saturated fat) will decrease blood cholesterol which in turn will decrease risk of heart disease. Rather than growing stronger as new data has accumulated over the last 40 years, today the diet-heart paradigm is on razor thin ice, and the temperature is increasing. To understand why as a country we went down this path, no one has written a more definitive in depth analyses than Gary Taubes in Good Calories Bad Calories and more recently in Why We Get Fat. While several lines of evidence from recent studies have illuminated the short-comings of low fat/high carbohydrate diets, the real question is whether low carbohydrate diets are a better alternative. All my research and that of several other groups have found that a well formulated low carbohydrate diet consistently improves all the features of metabolic syndrome including two of the most important risk factors for heart disease, the level of small LDL particles and the level of inflammation. The unremitting high prevalence of obesity, metabolic syndrome, and diabetes – all states that increase risk of heart disease but more importantly all states can best be described as carbohydrate intolerance – coupled with the very limited efficacy of traditional low fat diets may be a case of trying to fit a square peg in a round hole. Over the lifetime of each individual, a majority of us will find that we are better suited to a diet that restricts carbohydrate. Even if this is not you now, aging can often bring on carbohydrate intolerance with increasing weight, metabolic syndrome, or diabetes.

SNI:  What’s the data show regarding the effects of low carbohydrate diets on body composition?

Dr. Volek: We dedicate a complete chapter to body composition because it’s quite common to hear critics say that you can lose pounds faster on low carb diet, but it’s mostly water and muscle rather than body fat.There is an amazing story behind this myth that has survived over 30 years. In short, there is now overwhelming evidence that not only do groups of people randomized to a low carb diet lose more weight than on higher carb intakes, but they also lose more body fat. The myth of water and muscle loss came from brief studies (a few weeks or less) in people who never completed the adaptation phase of the low carb diet, in which there is often substantial water loss because of the diuretic effects of the diet. If you lose 5 pounds of fat and 5 pounds of water in the first 2 weeks, yes, half of your initial weight loss was not from fat. But if you then stay on the diet for 18 more weeks, losing two-and-a-half pounds of fat per week (but keeping all of your muscle), after 20 weeks you’ve lost 55 pounds, 50 of which was body fat. How to get this result, losing almost all fat and retaining or even increasing your strength and well-being, is explained as the sum of many factors which together we define as ‘a well-formulated low carb diet’.

SNI:  Can endurance and/or strength-power athletes follow a low carbohydrate diet?

Dr. Volek: YES and to appreciate how and why you need to understand keto-adaptation. Keto-adaptation, while well studied and documented, is not well-understood by most physicians, nutritionists/dietitians and trainers. This is primarily due to the emphasis in standard nutrition training placed on dietary carbohydrates for physical performance. Maintaining high carbohydrate availability is challenging and physiologically problematic, whereas switching metabolic preference to non-carbohydrate lipid-based fuels makes athletes get more out of their limited glycogen. Keto-adaptation affords even a very lean (10% body fat) athlete access to >40,000 kcal from body fat, rather than starting a prolonged event depending primarily on ~2000 kcal of glycogen. The human body takes at least 2 wk to complete metabolic adaptation to a very low carbohydrate diet, after which fat becomes its primary fuel. Additionally, keto-adaptation will likely reduce the inflammatory and oxidative stress response to exercise and allow for more efficient recovery.

A very low carbohydrate diet can also be followed by strength/power athletes. In one of our experiments, we had men train intensely with weights for 3 months while consuming either a very low carbohydrate diet or a low fat diet. The men consuming the low carb diet showed the greatest decreases in percent body fat and actually traded fat for muscle while improving functional capacity. Why would decreasing body fat be advantageous? Beyond the obvious aesthetic and health reasons, decreasing body fat is relevant for athletes who need to maintain a specific body weight as a demand of their sport (e.g., wrestling, boxing, powerlifting, Olympic lifting, judo, mixed martial arts, etc.) or for sports where physical appearance is a component of success (e.g., bodybuilding, gymnastics, dancing, fitness model competitions, figure skating, platform diving, etc.). From a functional perspective, a loss in body fat, and therefore body weight, improves the power to weight ratio, a very important determinant of endurance performance as well as speed and quickness which is relevant for athletes who participate in sports demanding short high-intensity and explosive bursts. Bottom line, there has been an overemphasis on the obligate nature of carbohydrate for athletes. A strong case can be made that lower carbohydrate intake or slow release forms of carbohydrate are preferred for active individuals seeking improvements in metabolic health and performance

SNI:  What are the top 3 myths regarding the effects of low carbohydrate diets?

Dr. Volek: Not including those issues discussed above, three additional myths revolve around these themes:

Saturated Fat is Harmful: Saturated fat gets blamed for a lot of bad things. The truth is that saturated fats only become problematic when they accumulate in the body. And the guilty party for saturated fat accumulation, in most cases, is dietary carbohydrate. This may seem counter-intuitive because we love to say “you are what you eat” but dietary intake of carbohydrate – not saturated fat – is the major driver of plasma levels of saturated fat. Prior studies have reported lower plasma levels of saturated fat in response to diets that contained 2-3 fold greater intake of saturated fat but were lower in carbohydrate. Even in controlled feeding studies in weight stable individuals (which necessitates a high intake of dietary fat), low carbohydrate diets decrease plasma saturated fat levels. In short, the level of carbs in the diet controls how you process saturated fat, keep carbs low enough and saturated fat becomes a preferred fuel, and this reduces their level in the blood.

Low Carb Diets Only Work Short-Term: Unfortunately, all too frequently people lose weight on a low carbohydrate diet and then promptly regain it all back. A common reason is they failed to view a low carbohydrate diet as a lifestyle. If you respond really well to a low carbohydrate diet as a weight loss tool, part of the reason is your willpower, but the other reason is that your body is probably not good at processing carbohydrates. For most people, this difficulty metabolizing carbohydrates does not go away even after you’ve lost some weight. So after losing 15 or 150 pounds, if you transition back to a diet with too much carbohydrate, you will likely regain much of the weight, even if the carbs you eat are the apparent ‘healthy’ ones. Yes, it is possible that you might be able to add some carbs back into your diet once you have reached your goal weight, but be very cautious. Listen to your body as much if not more than you listen to your dietitian. Adding back too much carbohydrate can put you on a slippery slope back to your former weight. To prepare yourself for long term success, from the very start you need to view your low carbohydrate diet as a permanent lifestyle, not just a temporary weight loss tool.

Low Carb Diets are Extreme: The mainstream nutrition establishment loves to claim that restricting an entire macronutrient class is extreme, especially carbohydrates which are known to give us quick energy. Encouraging moderation in all foods and a ‘balanced diet’ seems to make sense on the surface. After all, how can you argue against quick energy, moderation and balance? The answer depends to some degree on preconceptions around the meaning of moderation and what you consider ‘good’ nutrition. If consuming lots of carbohydrate provided some essential nutrient that would otherwise be lacking, then we might agree that a low carbohydrate diet is unbalanced or even extreme. But that’s clearly not the case. Think of it this way – what if you lived in California and planned a vacation in Hawaii. Would you believe someone who told you going that far was ‘extreme’, and therefore you ought to try flying just half way there instead? In this analogy, practicing this form of moderation would land you in seriously deep water. ‘Moderation’ and ‘balanced’ are meaningless terms when we are talking about ‘islands of safety’. And if your body is carbohydrate intolerant, eating a low carbohydrate diet is your island of dietary safety. Should a person with gluten intolerance consume moderate amounts of gluten so they can have a balanced diet? Of course not. Then why should a person with carbohydrate intolerance consume moderate amounts of carbs to meet some arbitrary criterion of a ‘balanced’ diet? From the point of view of essential nutrients and adequate energy to power your body, a low carbohydrate diet is ‘balanced’.

Source: Sports Nutrition Insider