The Case for Low Fat

By Dean Ornish, M.D.

Here's how you lose weight: burn more calories. Eat fewer calories. That's it. You can burn more calories by exercising. You can eat fewer calories by consuming less food. You can lose weight on any diet, but it is hard to keep the pounds off because you feel hungry and deprived. An easier way to consume fewer calories is to eat less fat, because there are nine calories in each gram of fat, whereas protein and carbohydrates have only four. So eating less fat allows you to consume fewer calories without eating less food.

I agree with the high-protein advocates that it is wise to eat fewer simple carbohydrates, like sugar, white flour and white rice. They are also low in fiber, so you get a lot of calories that don't fill you up. On top of that, simple carbohydrates get absorbed quickly, causing your blood sugar to zoom up. Your body responds by making more insulin, but too much insulin accelerates conversion of calories into body fat.

The goal, however, is not to go from simple carbohydrates to bacon and brie. Instead you should opt for whole foods with complex carbohydrates such as unrefined whole-wheat bread, brown rice, fruits, vegetables and beans. These are packed with thousands of protective substances. In addition, they are rich in fiber, which slows their absorption, thus preventing a spike in your blood sugar and an excessive insulin response.

On a high-protein diet, you may lose some weight because you are eating fewer simple carbohydrates. But you can lose even more weight by eating fewer simple carbohydrates and less fat. And you enhance your health instead of mortgaging it. Indeed, there is now evidence that a high-protein diet can actually decrease the flow of blood to the heart in patients with heart disease www.ornish.com)

The more closely and the longer people follow a low-fat, whole-foods diet, the more their heart disease improves. In our research, angina (chest pain) decreased 91%, and cholesterol levels fell 40%, without medications. Most patients eligible for bypass surgery or angioplasty were able to avoid it safely. These findings have been published in the leading peer-reviewed journals. Medicare now covers 1,800 patients in our lifestyle program.

I eat high-fat foods sometimes, but I don't delude myself into believing they are good for me. To get the full benefits of the good fats, you need to consume just three grams of fish oil or flaxseed oil a day.

You have a spectrum of dietary choices. But to the degree that you reduce simple carbohydrates and fat, you will lose weight and gain health.

Dr. Ornish is the founder and president of the Preventive Medicine Research Institute and the author of Eat More, Weigh Less