Replacing fat with carbs does no good

Low-fat diets that are high in carbohydrates are unlikely to improve your health, a new study shows.

Researchers studied the eating habits and health behaviours of 126,233 men and women who completed questionnaires every two to four years for up to 32 years.

The study, in JAMA Internal Medicine, found that replacing five percent of daily calories from saturated fats (mainly animal fat) with foods high in monounsaturated fat, such as olive oil and avocados, was associated with a 27% reduction in total mortality and fewer deaths from cardiovascular disease, cancer and neurodegenerative disease.

A similar switch from saturated fat to polyunsaturated fats, such as the omega-3 and omega-6 fatty acids in fish and walnuts, lowered total mortality by 13 percent and deaths from neurodegenerative diseases by 29%. But replacing saturated fats with carbohydrates, such as sugars and refined grains, did not confer any health benefits.

“Not all fats are created equal,” said the senior author, Dr Frank B Hu, a professor of nutrition at Harvard’s T H Chan School of Public Health. “We should eat more good ones from fish and avocados, instead of animal fats.”