Low-carbo diet better than low-fat to lower blood pressure

A low-carbohydrate diet may be better than a low-fat diet plus the weight-loss drug orlistat for its effect on helping lower blood pressure, a new study in Monday's Archives of Internal Medicine said.

Reseachers in U.S. picked up 146 overweight or obese adults who were randomly assigned to a low-carbohydrate diet or orlistat with a low-fat diet.

The average age of the study participants was 52 and the average body-mass index was 39 (30 and over is considered obese). Orlistat was marketed as Xenical, a prescription medication, and Alli, available over the counter.

The low-carb diet began with a carbohydrate intake of less than 20 grams of carbohydrates a day. The group taking orlistat received a 120-milligram dose of the drug three times daily and got less than 30 percent of their calories from fat.

Over 48 weeks, the low-carbohydrate group lost 9.5 percent of their body weight, while the orlistat group lost 8.5 percent. Insulin and glucose markers improved only in the low-carb group, and there was a significant drop in blood pressure in the low-carb group compared to the orlistat group. Similar reductions were seen for diastolic blood pressure.

"Weight loss was similar but substantial in both groups we studied, but blood pressure improved more in the low-carb dieters," said study author Dr. William Yancy Jr., an associate professor of medicine at Duke University Medical Center and a staff physician at the Department of Veterans Affairs Medical Center in Durham, N.C.

"There are options out there. Pick a diet you think you could stick to better, and work with your physician to help you target the right intervention for you," he advised.

Yancy said the blood pressure and cholesterol drops might have been even more impressive if people had stayed on their medications, but as they lost weight and normalized these readings, the doctors took them off blood-pressure and cholesterol drugs.

Obesity is a significant inducement to many illnesses, including heart disease, stroke, diabetes and many cancers.

"There are many paths to weight loss," said registered dietitian Karen Congro, director of the Wellness for Life Program at The Brooklyn Hospital Center in New York City. What often makes the difference in whether or not a diet is successful, she said, is whether or not there's a counseling and support component to the plan.

These studies show that you don't necessarily need to get to your "ideal body weight" to make substantial improvements to your health, she said. Losing 5 percent to 10 percent of your body weight can make positive changes in blood pressure, cholesterol and glucose control.

"If it can make you a healthier person, then a diet is a success," said Congro.

(Agencies)