Low Carb Diets Don't Raise Risk of Heart Disease
"It's not that the two diets are equally good," Harvard's Thomas Halton. "In fact, they're both equally bad."
"The way Americans are going low-fat is very unhealthy," Halton said. "They have a very high glycemic load. They're taking sugar. They're taking white bread. They're taking white rice and pasta. That certainly isn't the answer." Glycemic load is a combination of a food's glycemic index (a measure of how much a particular food raises blood sugar), and the amount of food eaten.
The study found one type of diet that reduced the risk of heart disease dramatically - by approximately 30% over 20 years. Women showed this much lower rate of heart attacks when they got their protein and fat from vegetable sources. These "good" protein sources included whole grains, beans, legumes, oatmeal and tofu. "Good" fat sources included olive oil, nuts and canola oil.
The study followed 82,802 female nurses for 20 years. The subjects were not dieting to lose weight, and in fact increased their Body Mass Index by 10% on average over the course of the study. "We didn't really design the study to look at weight loss," said Harvard's Frank Hu. But after looking at 20 years worth of data, the research team concluded that eating a moderately low-carb diet had "no long-term effect on bodyweight."