Just cutting 300 calories daily is all it takes to reduce CVD risk even in lean people, finds Clinical trial
New data from a two-year Duke Health trial suggests when it comes to cutting your risk for killer ailments such as diabetes and heart disease, there's always room for improvement. The results of the randomized, controlled clinical trial have appeared in the journal The Lancet Diabetes & Endocrinology.
The clinical trial, part of an ongoing project with the National Institutes of Health called CALERIE (Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy) continues to build on the researchers' hypothesis that it's not just weight loss that leads to these improvements, but some more complex metabolic change triggered by eating fewer calories than what's expended.
In adults already at a healthy weight or carrying just a few extra pounds, cutting around 300 calories a day significantly improved already good levels of cholesterol, blood pressure, blood sugar and other markers.
"There's something about caloric restriction, some mechanism we don't yet understand that results in these improvements," said the study's lead author William E. Kraus, M.D., a cardiologist and distinguished professor of medicine at Duke. "We have collected blood, muscle and other samples from these participants and will continue to explore what this metabolic signal or magic molecule might be."
For the first month of the clinical trial, participants ate three meals a day that would cut one-fourth of their daily calories to help train them on the new diet. They could choose from six different meal plans that accommodated cultural preferences or other needs. Participants also attended group and individual counselling sessions for the first six months of the trial, while members of a control group simply continued their usual diet and met with researchers once every six months.
Participants were asked to maintain the 25 per cent calorie reduction for two years. Their ability to do that varied, with the average calorie reduction for all participants were about 12 per cent. Still, they were able to sustain a 10-per cent drop in their weight, 71 per cent of which was fat, the study found. There were numerous improvements in markers that measure the risk of metabolic disease. After two years, participants also showed a reduction in a biomarker that indicates chronic inflammation which has also been linked to heart disease, cancer and cognitive decline.
"This shows that even a modification that is not as severe as what we used in this study could reduce the burden of diabetes and cardiovascular disease that we have in this country," Kraus said. "People can do this fairly easily by simply watching their little indiscretions here and there, or maybe reducing the amount of them, like not snacking after dinner."