ATLANTA – The Atkins diet may have proved itself after all: A low-carb diet and a Mediterranean-style regimen helped people lose more weight than a traditional low-fat diet in one of the longest and largest studies to compare the dueling weight-loss techniques.
A bigger surprise: The low-carb diet improved cholesterol more than the other two. Some critics had predicted the opposite.
“It is a vindication,” said Abby Bloch of the Dr. Robert C. and Veronica Atkins Foundation, a philanthropy group that honors the Atkins diet’s creator and was the study’s main funder.
However, all three approaches – the low-carb diet, a low-fat diet and a so-called Mediterranean diet – achieved weight loss and improved cholesterol.
The study is remarkable not only because it lasted two years, much longer than most, but also because of the huge proportion of people who stuck with the diets – 85 percent.
Researchers approached the Atkins Foundation with the idea for the study. But the foundation played no role in the study’s design or reporting of the results, said the lead author, Iris Shai of Ben-Gurion University of the Negev.
Other experts said the study – being published today in the New England Journal of Medicine – was highly credible.
“This is a very good group of researchers,” said Kelly Brownell, director of Yale University’s Rudd Center for Food Policy and Obesity.
The research was done in a controlled environment – an isolated nuclear research facility in Israel. The 322 participants got their main meal of the day, lunch, at a central cafeteria.
Average weight loss for those in the low-carb group was 10.3 pounds after two years. Those in the Mediterranean diet lost 10 pounds, and those on the low-fat regimen dropped 6.5.
More surprising were the measures of cholesterol. Critics have long acknowledged that an Atkins-style diet could help people lose weight but feared that over the long term, it may drive up cholesterol because it allows more fat.
But the low-carb approach seemed to trigger the most improvement in several cholesterol measures, including the ratio of total cholesterol to HDL, the “good” cholesterol.