Exercise and Low Carb Diets (with Stephen Phinney)
Theme: Nutrition and Health
Air Date: 2/5/06
Producer: Shelley Schlender
Description: Experts discuss how the Inuit of the Arctic Circle ran 30 miles a day on a low carb diet and how professional bicylists can eat this way.
(EXTENDED HOST INTROS) Peope who love to exercise like to enhance their experience by building speed, power, endurance. Ask most health experts what foods help to achieve these goals, and you?re likely to hear about a high carbohydrate diet?fruit, pasta, bagels, granola bars, rice . . . Even if you don?t exercise very much, the general opinion today is that you have to eat plenty of carbs, or else you might feel sick. For instance, physicans often report in their clinical experience that patients who switch to a low carb diet frequently complain of being light-headed, weak and easily tired.
But if all this is true, how do you explain the Inuit people of the Arctic who could run 30 miles a day beside their sleds, all on a diet that may have been around 85 percent fat, 15 percent protein, and basically carbohydrate free? Some researchers claim it?s because the Inuit are genetically unique. Then how do you explain an explorer named Stephanson who lived among the Inuit, ate what they ate, and stayed healthier than explorers eating European food? What about the professional cyclists in the 1970s who ate inuit style for over a month. The more they adapted to a high fat, very low carb diet, the more they could exercise just as fast and long as they had when they were eating mostly carbs. The key was, they had to adapt . . . And that didn?t happen overnight or in a few days. It took several weeks. And that adaptation period much longer than few-day or few week clinical studies that are conducted these days, in order to set public policy about whether people who want to exercise can ever adapt to a low-carb diet.
These are facts in the history of nutrition that Stephen Phinney may know better than anyone else in the world. Phinney is a medical doctor, phD researcher, and professor emeritus of medicine at the University of California, Davis. Up next, we?ll talk with Steve about how he became interested in the relationship between exercise and low-carb diets.
We?ll begin by catching up with Steve at the annual conference of the Nutrition and Metabolism Society, where he was an award-winning, featured speaker. We met him at breakfast. It turns out that he?s a trim, muscular, alert-looking man who put a lot of scrambled eggs on his plate and not a single piece of toast. In fact, Steve said he tends to eat less that 50 grams of carbohydrates a day. In contrast, the Nutrition Practice Guidelines published by the American Diabetic Association state that humans need a minimum of 130 grams of carbohydrate per day for the brain, muscles and other organs to function adequately. Steve Phinney says that he generally eats 80 grams a day LESS than that, and he looks to be in top physical condition. But you might want to listen closely, to see what you think about whether the American Diabetic Association is correct in their assertion that a low carb diet is inadequate for the brain.
(INTERVIEW WITH DR. PHINNEY)
MID-SHOW BREAK: Steve Phinney points out that today, the last pure hunting cultures among the peoples of North America have mostly died out, along with their higher exercise lifestyle that was fueled by high-fat, adequate protein, very low carbohydrate diets. According to the American Diabetic Association, eating such a low carb diet was probably bad for them anyway, and the modern American diet is healthier. After all, it?s lower in fat, and higher in carbs, such as the ones recommended on a typical ADA menu plan--bananas, sweet potatoes, noodles, bagels, soda crackers, low-fat milk. As native peoples have switched to more carbs, the rates of obesity and diabetes have skyrocketed, and the deep knowledge of how hunter gatherers maintained their physical performance on a low carb diet has been lost.
I?m Shelley Schlender. This is For Your Health. While there has been very little funding for exploring the relation between low-carb diets, health and athletic performance, some doctors and scientists continue to study the issue. Up next, we continue our conversation with Stephen Phinney, joined now by Eric Westman and Jay Wortman. Eric Westman is a Medical Doctor and scientist with Duke University, where he has led some of the world?s most well-documented studies about the long-term effects of low-carb diets, studies which have indicated that they can be both effective and safe. Westman?s findings have been published in prestigious medical journals such as the Annals of Internal Medicine. Jay Wortman is a medical doctor who was born in a remote part of northern Alberta that used to be a Hudson Bay trading post. Jay was raised in a log house on the banks of the Peace River. Now he?s a Medical Doctor and Regional Director for Health Canada, First Nations and Inuit Health Branch. In this position, he?s working to help first nations people return to a diet closer to the low-carb version that kept them healthy for generations.
(INTERVIEWS WITH DRs PHINNEY, WORTMAN and WESTMAN)
SHOW CLOSE: I?m Shelley Schlender. This is For Your Health on KGNU Boulder-Denver and Beyond. You?ve been listening to three of the world?s experts on the effects of low-carb diets on health and athletic performance. Stephen Phinney is a medical doctor, phD researcher, and professor emeritus of medicine at the University of California, Davis. Eric Westman is a medical doctor and researcher at Duke University. Jay Wortman is medical doctor and Regional Director for Health Canada, First Nations and Inuit Health Branch. You can read about some of their research by going to the website for the Nutrition and Metabolism Society, nmsociety.org.