Can a low carb diet help your heart health?

Instead, the researchers designed what they saw as practical and relatively healthy diets for each group. All attendees ate vegetable omelets, black bean chicken burritos, seasoned London Broil, veggie chili, cauliflower soup, grilled lentil salads and grilled salmon. But the high-carb group also ate foods like whole wheat bread, brown rice, multigrain English muffins, strawberry jam, pasta, skim milk, and vanilla yogurt. The low-carb group skipped bread, rice, and fruit spreads and sweet yogurt. Instead, their meals contained higher fat ingredients such as whole milk, cream, butter, guacamole, olive oil, almonds, peanuts, pecans, and macadamia nuts, as well as soft cheeses.

After five months, people on a low-carb diet did not experience any detrimental changes in their cholesterol levels, despite the fact that 21 percent of their daily calories came from saturated fat. This amount is more than double what the federal dietary guidelines recommend. Their LDL cholesterol, the so-called bad guy, for example, stayed about the same as those on a high-carb diet, which got just 7 percent of their daily calories from saturated fat. Tests also showed that the low-carb group had about a 15% reduction in their levels of lipoprotein (a), a fatty particle in the blood that is strongly linked to the development of heart disease and stroke. cerebral.

The low-carb group also saw improvements in metabolic measures linked to the development of type 2 diabetes. The researchers assessed their lipoprotein insulin resistance scores, or LPIR, a measure of resistance to insulin which examines the size and concentration of molecules carrying cholesterol in the blood. Large studies have shown that people with high LPIR scores are more likely to develop diabetes. In the new study, people on a low-carb diet saw their LPIR scores drop by 15% – reducing their risk of diabetes – while those on a high-carb diet saw their scores increase by 10%. People on a moderate carbohydrate diet had no change in their LPIR scores.

The low carb group also saw other improvements. They had a drop in their triglycerides, a type of fat in the blood that is linked to heart attacks and strokes. And they’ve had increases in their levels of adiponectin, a hormone that helps reduce inflammation and make cells more sensitive to insulin, which is a good thing. High levels of body-wide inflammation are linked to a range of age-related illnesses, including heart disease and diabetes.

The low-carbohydrate diet used in the study largely eliminated highly processed and sugary foods while making room for “high-quality” carbohydrates from whole fruits and vegetables, beans, legumes, and others. plants, said Dr. David Ludwig, study author and an endocrinologist at Harvard Medical School. “It is primarily focused on eliminating processed carbohydrates, which many people now recognize are among the less healthy aspects of our food supply,” said Dr. Ludwig, co-director of the New Balance Foundation Obesity Prevention Center at Boston Children’s Hospital. .

Dr. Ludwig pointed out that the results do not apply to the very low carbohydrate levels typical of ketogenic diets, which cause LDL cholesterol to rise sharply in some people. But he said the study shows people can achieve metabolic and cardiovascular benefits by replacing processed carbohydrates in their diets with fats, including saturated fat, without making their cholesterol levels worse.

The new study cost $ 12 million and was largely funded by the Nutrition Science Initiative, a nonprofit research group. It has also been supported by grants from the National Institutes of Health, the New Balance Foundation, and others.