How the Atkins Diet Fares in Cholesterol
Atkins-Like Diet Worse for Cholesterol Compared to South Beach, Ornish Diets, Study Says
Atkins, South Beach, and Ornish continued...
The researchers conducted blood tests throughout the study to assess risk factors for heart disease, including LDL (bad) cholesterol, triglycerides, and C-reactive protein, which is a measure of inflammation in the body.
They also used ultrasound to study changes in blood vessels' flexibility -- specifically, their ability to widen to accommodate blood flow. Atherosclerosis, the hardening of the arteries, hinders that process and is associated with heart attack and stroke risk.
The study revealed that:
- While on the low-carb, high-fat diet, LDL cholesterol levels increased slightly, compared to decreases of about 12% and 17% respectively, during the South Beach and Ornish phases of the study.
- After a month on the Atkins-like diet, study participants showed less blood vessel flexibility than they did after a month on the Ornish diet.
- CRP levels remained in the normal range with all three diets, but levels went down slightly while participants were on the South Beach and Ornish diets and they went up slightly on the high-fat, low-carb diet, Miller tells WebMD.
The study appears in the April issue of the Journal of the American Dietetic Association.
Miller says the study makes it clear that high-saturated fat diets are pro-inflammatory and that they promote heart disease in other ways as well.
But a spokeswoman for Atkins Nutritionals says the eating plan the study participants followed in no way resembles what is recommended for weight maintenance.
In an email exchange with WebMD, Atkins Vice President of Nutrition and Education Colette Heimowitz, MSc, says that on the maintenance phase of the Atkins diet, fat should make up no more than 40% of total calories, and no more than 10% of calories should come from saturated fat.
The study participants typically ate about three times as much saturated fat as they should have if they were following Atkins for weight maintenance, she says.
Heimowitz says that Atkins dieters consistently show improvements in blood fats, or lipids, in the form of decreased triglycerides. But this improvement was not seen in the study participants while they were on the low-carbohydrate, high-fat diet.