Diet fads come and go and recently we have seen an explosion in Atkins-type diets that restrict carbohydrates primarily. Most people I know have been on one at some time in the past 8 years or so. The South Beach Diet is a popular version of the low carb approach that has many followers and specially prepared and marketed meals to help those trying to follow the diet.
My own experience has been positive with low-carb diets. About 4 years ago I lost about 20lbs over about 6 weeks and pretty much kept it off. Once past the initial strict no-carb phase, the palate adjusts and high sugar food no longer seems appealing, for me at least.
So if low-carbs can drop the weight, what about the effect of the higher fat intake on blood lipids and cholesterol? According to a study that came out in The New England Journal of Medicine in July 2008, it seems the approach might actually be good for your cholesterol too.
Many studies have been done on the effect of various diets to help a person lose weight but this study is unique in that is followed overweight (average body-mass-index was 31) subjects for 2 years on each of three diets. Most of the participants were men and the study was conducted in Israel.
Here are the three test diets:
Mediterranean diet with restricted calories:
Low in red meat, lots of vegetables, fish and chicken replaced most red meat. Fat was derived from olive oil and five to seven nuts each day, and comprised less that 35% of the total calories consumed (1500 for women, and 1800 for men).
Low-fat diet with restricted calories:
Low-fat grains, vegetables and fruits were encouraged. Total calorie intake was 1500 for women and 1800 for men, with 30% from fat (10% from saturated fat). The diet was based on the American Heart Association guidelines.
Low-carb diet with unrestricted calories:
Low in carbohydrates-20g per day initially with gradual increase to 120g to maintain weight loss. Participants were encouraged to eat vegetarian sources of fat and protein but had not restriction on the number of calories they could eat. The diet was based on the Atkins diet.
Results
Low-carb dieters lost the most weight (about 12lbs on average) and had the best cholesterol data by the end of the study. Both the low-carb and the Mediterranean diet produced greater weight loss than the low-fat diet but all groups lost weight. Fasting glucose was only decreased in the Mediterranean diet suggesting this approach might be best for diabetics.
So which diet?
My take is that you can have your fats or you can have your carbs, but you can't have both. Also, the carbs should be good ones, ie no white bread and white pasta, and definitely no sugar. The fats should not be saturated ideally, do olive oil instead of butter whenever possible. However you look at this study, it shows that you can eat a low-carb diet with no calorie restrictions, and get the same or better effects than if you restrict your calorie intake through low fats, or take the Mediterranean approach. In my experience, the low-carb diet reduces appetite which may lead to lower calorie consumption anyway.
So…my preference is for low-carb. You can still eat well, the food tastes good and once initiated, you don't miss the sugar. Oh, and it's good for your cholesterol. If you are diabetic, then go Mediterranean. No matter which diet you choose, you will lose weight, and if you add a little exercise, your weight loss will be amplified and you will feel that much better!
