A plant-based diet boosts after-meal calorie burn, leads to weight reduction, and improves cardiometabolic risk factors in obese individuals, according to a new randomized control trial printed in JAMA Network Open by researchers with the Physicians Committee for Responsible Medicine.
The study randomly assigned participants–who were overweight and had no history of diabetes to an intervention or control group in a 1:1 ratio. For 16 months, participants in the intervention team followed a low-carb, vegetarian diet predicated on fruits, vegetables, whole grains, and legumes without a calorie limitation. The management group produced no diet adjustments. Neither group shifted exercise or medication routines, unless directed by their personal doctors.
Researchers used indirect calorimetry to measure the amount of calories participants burned following a standardized meal at both the start and end of the analysis. The plant-based group increased after-meal calorie burn 18.7%, typically, following 16 weeks. The control group team’s after-meal burn did not change significantly.
“These findings are groundbreaking for the 160 million Americans struggling with overweight and obesity,” says study author Hana Kahleova, MD, PhD, director of clinical research for the Physicians Committee. “Over the course of years and decades, burning more calories after every meal can make a significant difference in weight management.”
Within only 16 months, participants in the group lowered their body fat by 6.4 kg (approximately 14 lbs ), normally, compared to an insignificant shift in the management group. The plant-based group experienced greater after-meal calorie burn and additionally saw substantial drops in fat mass and visceral fat quantity –the harmful fat located around the inner organs.
The researchers also worked with with Yale University researchers Kitt Petersen, MD, and Gerald Shulman, MD, to monitor intramyocellular lipid and hepatocellular lipid–the amassing fat in liver and muscle cells–in a subset of participants using magnetic resonance spectroscopy. Those from the plant-based group increased after-meal calorie burn, decreased the fat within the liver and muscle tissues by 34 percent and 10%, respectively, while the control group didn’t undergo significant changes. Fat stored in such cells has been associated with insulin resistance and type 2 diabetes.
“When fat builds up in liver and muscle cells, it interferes with insulin’s ability to move glucose out from the bloodstream and into the cells,” adds Dr. Kahleova. “After just 16 weeks on a low-fat, plant-based diet, study participants reduced the fat in their cells and lowered their chances for developing type 2 diabetes.”
The analysis also provided new insight into the connection between fat within the cells and insulin resistance. The plant-based group increased their after-meal calorie burn, diminished their fasting plasma insulin concentration from 21.6 pmol/L, diminished insulin resistance, and increased insulin sensitivity–all favorable results–while the control group found no important alterations.
The plant-based group also decreased total and LDL cholesterol from 19.3 Mg/dL and 15.5 mg/dL, respectively, without any significant changes in the management group.
“Not only did the plant-based group lose weight, but they experienced cardiometabolic improvements that will reduce their risk for type 2 diabetes, heart disease, and other health problems,” says Dr. Kahleova.
“I plan to stay on this diet for good. Not just for 16 weeks, but for life,” reports study participant Sam T., who lost 34 pounds and improved his metabolism during the 16-week study. Since the study has concluded, Sam has continued a plant-based diet, reached his goal weight, and began running half-marathons and marathons.
Related Journal Article: https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2773291