Dr. Frank Sacks

Can a high fat diet really help you lose weight? A recent trial led by Dr. Frank Sacks of the Harvard School of Public Health Department of Nutrition says it can. Dr. Sacks and colleagues at the Brigham and Women's Hospital followed two groups of middle age women who weighed an average of two hundred pounds. One group ate a low fat diet keeping their fat intake to just 20% of their daily calories. The second group ate a high fat diet consuming as much as 35% of calories from fat. At the end of six months, both high and low fat groups had lost weight but those who ate the high fat diet have kept the weight off the longest -- eighteen months and counting.

Dr. Sacks's study sheds new light on the puzzling fact that despite the popularity of low fat foods; obesity is reaching epidemic proportions in America. So what is making us fat? More clues lie in the results of a ten-year, seven countries study done between 1958 and 1975 by Dr. Ansel Keyes. Dr. Keyes found that rates of heart disease and amounts of fat intake varied from country to country. But the correlation between fat intake and heart disease was not quite what you would imagine. The people of Crete, for example, ate a diet with as much as 43% fat but had the lowest rates of heart disease. The study revealed that it was not fat per se but the type of fat that mattered. The saturated fats found in red meat or butter were bad but unsaturated fats found in olive oil or nuts were beneficial. Unfortunately, by the 1970's the message from the scientific community was that all fats were bad giving rise to our current low fat culture.

The experience of the last ten years offers solid proof that it is the type of fat and not the amount. Despite our fixation with eliminating fats, rates of obesity rose precipitously in the U.S. throughout the 1990s. Using the body mass index as guide, obesity has increased 44% since 1991. The body mass index or BMI, is simple and accurate way of using height and weight to determine if your weight is healthy. To determine your BMI, divide your weight in kilograms by height in meters squared. A person with a BMI of 25 to 29.9 is considered overweight. A BMI of greater than 30 is an indicator of obesity. In the U.S. today, over two-thirds of the adult population has a BMI of greater than 25 placing them at greater risk to develop a variety of health problems.

So what does this mean for those hoping to lose or maintain weight? Dr. Sacks's study showed that in terms of weight loss, the high fat diet was just as effective as a low fat diet and maybe even more effective when you consider the ease with which participants were able to remain on the program for longer periods of time. Study participants who ate the higher fat diet felt more satisfied, were less likely to cheat, and because they had a greater range of foods to choose from did not feel bored or deprived as the low fat group.

Yours in health,
Mollie