Which makes you fat: Carbs or fats?

One of the problems in the field of nutrition is that many of the experts violently disagree with each other. Most nutritionists and dieters circle their wagons with one group or another one. Low-fat vs. low-carb is one such dichotomy.

Diets work by restricting the quantity and/or variety of foods you eat. It has been shown that when you restrict people’s choices of food the amount of food they eat goes down. If you go on a diet of grapefruit juice and rutabagas you’d loose weight. Even if you love grapefruit and rutabagas you would quickly tire of only having these two choices and eat a lot less. I heard one walpaper hanger who was on Atkin’s say that sometimes she was so hungry for carbs that even the wallpaper paste started to look good to her and by then she was so tired of steak, cheese and butter that even the thought of them made her feel ill. Extreme diets are unsustainable. Dieters go on them, loose a boatload of weight, then when their willpower wears thin they go off the wagon and gain the weight back.

My toughest diet was when I was in my late 20’s. I hadn’t been to my doctor for several years and when I went in for something he noticed that I gained 40 lbs since my last visit. Discovering I was a vegetarian I was refered to a colleague who was both a doctor and a nutritionist and who worked a lot with Seventh Day Adventists so she was familiar with vegetarianism. I did a baseline and discovered that I was eating 5,000-10,000 kcal/day. She put me on 1,800 kcal/day diabetic exchange diet. At first the weight just flew off; I lost 10 lbs in the first 2 weeks and all my friends noticed I’d lost weight. After that it slowed to about a pound a week. I was literally hungry all the time; I was eathing enough so I didn’t feel physically weak but never enough to be free of hunger. I didn’t know it but I was in starvation mode. According to mathematics since a lb of fat represents 3,500 kcal I should have been loosing about a pound/day but when food gets scarce your body adjusts by holding onto every calorie you consume. In a year I lost 50 lbs before getting so tired of the constant hunger that I had to quit. I do credit that year with giving me a lot of good habits, it got me eating more fruits, vegetables, and whole grains. Before the diet I largely lived on beer, pizza, raman noodles, and cheap boxed macaroni & cheese dinners (student food).

Sika went through the Glycemic Index and Glycemic Load areas pretty quickly. I’m not a fan of Glycemic Index because it villifies a lot of good foods. Look at carrots; with a GI of of 131 this seems much worse than pasta which has a GI of 71. Carrots will spike your blood sugar and require more insulin than pasta right? Not so quick! a typical serving of carrots might have 4 gm of carbs while a typical serving of pasta might have 40 gm. Even though the sugar in carrots gets into your blood quickly there isn’t that much of it. To deal with this issue Glycemic Load has been introduced which takes in consideration the GI and the amount of carbs in a serving. The GL of a serving a carot is 5.2 while the GL of a cup of pasta is 28. Potatoes look like an evil food when you look at its GI of 131. However, a large 1 lb. potato only has 300 kcal. A potato this big is very satesfying for the small number of calories. It would be hard for someone to eat a 10 lb bag of potatoes in a day but the whole bag would supply only 3,000 kcal. Potatoes can be a great diet food (assuming you won’t smother them with butter and sour cream).

Personally I have more faith in low fat than low carb. Carbohydrates are the body’s most efficient fuel. The doctors who have had the most success reversing heart dissease have advocated low fat diets. We obviously need some fat and we also need all of the essential fatty acids though not all fats are created equal. From a weight loss point of view low carb diets seem the most effective. Then again people in chemotherapy loose weight too; the fact that something makes you loose weight does not guaranty that it is healthy.

Like I said above, extreme diets are unsustainable. Depending on your level of will power you might last a day, a week, a month, or a few years but eventually you will tire of these rigorous regemins. A more reasonable approach is to make moderate improvements in your diet and make them permanent. Don’t view a diet as a quick fix you can abandon after you meet your goals but as a permant change. If you love chocolate don’t decide to never eat another bite. Perhaps switch to dark chocolate, smaller servings, or don’t have it quite as often. If you always feel deprived than you will have a tougher time staying on it.