So You Need to Lose Weight
by Carolyn McClanahan

            This final section covers diet strategies for runners (and exercise nuts in general) who want to lose weight and some healthy diet tips for those who don't need to lose weight.
 

Diets for weight loss               As you now know, to lose a pound requires the expenditure of 3,500 calories and it doesn't really matter how it happens. Popular ways include decreasing carbohydrates, as in the Atkins or South Beach diet, or decreasing fat, such as the Ornish diet. Other diets focus on calorie reduction across the board: Weight Watchers, Jenny Craig, SlimFast, etc. These diets tend to be low in fat because fat contains more calories per gram (9) than do carbohydrates and protein (4). The current fad is low carb, so I will briefly discuss the popular low-carb diets and then give my thoughts on how these relate to runners.
 

Atkins     The Atkins diet is the classic low-carb diet. Dr. Robert Atkins was a cardiologist who in 1972 boldly challenged the establishment that low-fat diets were healthy. He felt that insulin was the real culprit in heart disease and that carbohydrates were bad because of insulin stimulation. His original diet included fats of all kind, including those evil trans fats and saturated fats we discussed last month. Research substantiated his original thoughts on insulin and heart disease, but it also disproved that all fats are good. He revamped his diet in the late 1990s and called for a reduction of the evil fats. However, he still felt that too many carbs were bad and needed to be restricted.
          The Atkins diet has a very restrictive induction phase of two weeks. Carbohydrate intake is limited to 20 grams per day (3 cups of loosely packed salad). After the two-week induction phase, carbohydrate intake is increased by 5 grams per day each week (so week 3 is 25 grams of carbs a day, week 4 is 30 grams, etc.). This is done until weight loss stops and this threshold is called the Critical Carbohydrate Level for Losing. Some people may lose weight at 50 grams a day, while others may stop at 30 grams per day. After weight loss is complete, one goes to a maintenance phase so weight is not regained.
 

South Beach       The South Beach Diet is less restrictive than the Atkins. Dr. Arthur Agatston (another cardiologist) developed a much friendlier version of the low-carb craze. He feels there are good carbs and bad carbs, just as there are good fats and bad fats. Generally, the first two weeks are an induction phase that allows very low-glycemic carbs. After that, it allows greater choice in the type of carbohydrates available. However, he does focus on avoiding high-glycemic carbs and the evil fats on a continuing basis.
 

My thoughts for runners     The best way to lose weight is a combination of increased activity and decreased food intake. The theory behind the low-carb diets is fine, but both of these diets were designed for the relatively sedentary general population. As we all know, runners are not part of this typical general population. One may function OK on a low-carb diet if exercise consists of a "stroll" down the street; however, anything faster than a 15-minute mile is hard to maintain without the quick energy one gets from carbohydrates.
          Studies are showing that a balanced diet consisting of lower-glycemic carbs, good fat and protein helps to prevent diabetes and heart disease. A good way to lose weight is to follow this type of diet, but be aware of the calorie intake and adjust down to the level that your body needs (as discussed in my first article).
          If you prefer a strict, step-by-step diet to lose weight, and really want to spend your money on a book, the best bet to me is the South Beach Diet. Keep in mind, if you want to run, you may have to skip the induction phase.
          For runners who don't need to lose weight, I suggest a couple of things. If you do a pre-run meal, make it a mix of carbs, proteins and good fat instead of strictly carbs. This will provide a steadier glucose level for a longer period of time. The same goes for after a race or hard run. Adding fat or protein to that banana will slow the absorption and provide a steadier glucose level.

          Remember: Slow and steady wins the race (and lessens the risk of diabetes and heart disease).
 

Carolyn McClanahan, M.D., is a family physician, runner and expert dieter.