(NaturalNews) A low-carb vegan diet leads to more weight loss and a better cholesterol profile than a high-carb vegetarian diet, according to a study conducted by researchers from the University of Toronto, St. Michael's Hospital (Toronto), Boston Children's Hospital, Harvard Medical School, New York Medical College and Solae LLC, and published in the journal BMJ Open in February 2014.
"A self-selected low-carbohydrate vegan diet, containing increased protein and fat from gluten and soy products, nuts and vegetable oils, had lipid lowering advantages over a high-carbohydrate, low-fat weight loss diet, thus improving heart disease risk factors," the researchers wrote.
Prior studies have shown that certain low-carbohydrate diets may assist in weight loss, while others have shown that protein and fat from vegetable sources may lower the risk of heart disease. The current study sought to examine both of these factors together, in the form of a low-carb vegan diet.
Improved heart health
Thirty-nine overweight adults with high levels of blood lipids (hyperlipidemia) were recruited from the first phase of the study in which all their meals had been provided for them for a full month, consisting of either a low-carb vegan diet or a high-carb lacto-ovo vegetarian diet. Participants were asked to continue the same eating patterns for six months on their own. At the beginning and end of the study, researchers measured each participant's weight, blood pressure, blood sugar and blood lipids, including cholesterol and LDL ("bad") cholesterol.
A vegan diet is one that does not include any animal-derived foods, including flesh, dairy or eggs. A lacto-ovo vegetarian diet does not include flesh (meat, poultry or seafood) but does include eggs and dairy.
Participants on the low-carb vegan diet were instructed to get 26 percent of their calories from carbohydrates, 31 percent from protein and 43 percent from fat; participants on the high-carb vegetarian diet were instructed to get 58 percent of their calories from carbohydrates, 16 percent from protein and 25 percent from fat. Low-carb vegan participants were encouraged to eat soy and nuts, high-fiber foods such as oats and barley, and low-carbohydrate vegetables such as eggplant and okra. High-carb vegetarian participants were encouraged to eat whole wheat grains, low-fat or skim dairy and liquid egg substitutes.
All study participants lost weight over the course of the trial, but participants on the low-carb vegan diet lost significantly more (15.2 vs. 12.8 pounds). Their LDL cholesterol, total cholesterol and triglyceride levels also significantly decreased relative to the high-carb vegetarian group, indicating lower cardiovascular risk.
There was no significant difference in blood pressure, blood glucose or insulin resistance between the two groups.
"We conclude that a weight loss which reduced carbohydrate in exchange for increased intakes of vegetable sources of protein, such as gluten, soy and nuts, together with vegetable oils offers an opportunity to improve both LDL cholesterol and body weight, both being risk factors for coronary heart diseases," the researchers wrote.
Further research needed
The researchers did indicate some limitations in their research, suggesting that further studies are needed to confirm the results.
The study involved a small number of total participants and had a high dropout rate in both comparison groups. In addition, first author David J. A. Jenkins and other researcher disclosed that they had served on advisory boards or received money from numerous food companies, including the Almond Council of California, the Canola Council of Canada, the International Tree Nut Council Nutrition Research and Education Foundation, Kellogg's, the Peanut Institute and Quaker Oats. The study was also partially conducted and funded by Solae LLC, a food and feed company that focuses on soy.
Other funding came from Loblaw Companies Limited and the Canada Research Chair Program of the Federal Government of Canada.