Losing weight naturally might be as easy as adding legumes to your plate, while replacing meat and animal products with a low-fat vegan diet. A new study suggests that increasing consumption of plant-based whole foods, especially legumes, while decreasing consumption of meat, fish, poultry and oil, can lead to significant weight loss and a decrease in body fat.

The study, published in The Journal of the Academy of Nutrition and Dietetics, found that not only does eating a plant-based diet rich in legumes help you lose weight but can shift body composition to reduce body fat, and also lower insulin sensitivity in overweight adults.

This research, conducted by MDs, RDs, and other accredited experts in plant-baed nutrition, adds to a growing body of research connecting plant-based foods to natural weight loss.

Conducted by the Physicians Committee for Responsible Medicine (PCRM), this 16-week study observed 244 overweight adults randomly assigned to one of two groups. Half of the participants ate either a low-fat vegan diet or were asked to make no dietary changes at all. To properly analyze the connection between diet and weight loss, the researchers recorded the body weight, fat mass, diet quality, and insulin sensitivity of both groups over the period of the study. The final data included the records of 219 participants.

Those study subjects who followed the plant-based diet high in legumes lost on average 13 pounds and 9.1 pounds of fat mass over 16 weeks. The subjects who made no dietary change showed no equivalent weight loss and essentially stayed the same in terms of body fat and other measurements. Both groups ate approximately the same number of calories.

The study concluded that just by increasing your intake of plant-based foods (fruits, legumes, meat alternatives, whole grains) and decreasing the amount of animal products and oils you eat, you can achieve substantial weight loss.

Vegan Diet High in Legumes Most Effective for Weight Loss

The study examined the dietary differences between the vegan participants to determine what plant-based foods were most associated with the greatest weight loss. The PCRM  researchers found that an increased level of legume consumption correlated with the highest weight loss and most dramatic reduction of body fat. Overall, the study showed that all plant-based foods helped participants decrease body weight, but legumes were most effective.

“Our research shows that the best way to improve the quality of your health is to improve the quality of the foods you eat,” Director of Clinical Research at PCRM and co-author Hana Kahleova, MD, Ph.D., wrote in a statement. “That means avoiding animal products and eating a vegan diet rich in fruits, vegetables, grains, and beans.”

Legumes are a group of plant foods that include:

  • Chickpeas
  • Peanuts
  • Black beans
  • Green peas
  • Lima beans
  • Kidney beans
  • Black-eyed peas
  • Navy beans
  • Pinto beans
  • Soy Beans
  • Lentils
  • Great American beans

Legumes are high in fiber, contain protein and are low in fat and have zero cholesterol. While they contain complex carbohydrates, they also deliver a host of antioxidants that energize the body while not producing surges in blood sugar, so they help keep you full while providing steady energy, both helpful when it comes to reducing body fat and achieving weight loss.

Results of the Study: Legumes Help Achieve Weight Loss

In the vegan group, intake of fruit, vegetables, legumes, meat alternatives, and whole grains significantly increased while intake of meat, fish, and poultry, dairy products, eggs; nuts and seeds and added fats decreased.
The most weight loss was associated with the highest intake of legumes, as well as the lowest intake of meat, fish and poultry. Those consuming a low-fat vegan diet also increased their intake of carbohydrates, fiber, and several micronutrients and decreased fat intake.
Reduced fat intake was also associated with reduced body weight as well as reduced fat mass and improved measures of insulin resistance

In the conclusion of the study, the authors wrote: "When compared with participants’ usual diets, intake of plant foods increased, and consumption of animal foods, nuts and seeds, and added fats decreased on a low-fat vegan diet. Increased legume intake was the best single food group predictor of weight loss."

Eat Plant-Based to Improve Your Health

The study primarily highlights how animal products also contribute to weight gain or an inability to decrease weight. Reducing fish, meat, and poultry consumption showed significant connections with weight loss. The researchers even noted that decreasing egg and high-fat dairy consumption correlated with decreased weight and fat mass.

The research team also examined how the diet quality matched up to the Alternative Healthy Eating Index-2010 (AHEI) – a rubric designed by the Havard School of Public Health to gauge the relationship between diet and chronic illness. The vegan participants displayed an average increase of six points in contrast to the stagnant diet group. Now, the PCRM aims to show how beneficial plant-based foods can be for weight loss and general health.

“Previous studies have suggested that both Mediterranean and vegan diets improve body weight and cardiometabolic risk factors, but until now, their relative efficacy had not been compared in a randomized trial,” Kahleova said last month. “We decided to test the diets head to head and found that a vegan diet is more effective for both improving health markers and boosting weight loss.”

Eating Plant-Based Can Help Diabetics

This May, Danish researchers presented data at the European Congress on Obesity that asserted that switching to a vegan diet for three months significantly curbed the symptoms of diabetes. The study revealed that diabetics could alleviate some of their severe symptoms by altering their diets The participants that followed the vegan diet reduced their average weight by 9 pounds and lowered their body mass index in every trial.

The Department of Nutrition at Harvard’s T.H. Chan School of Public Health released a study that claims that a plant-based diet full of fruits, vegetables, legumes, and nuts could lower your risk of developing type 2 diabetes. Current reports show that 90 percent of diabetes cases diagnosed are type 2 diabetes – meaning related to lifestyle choices, diet, and exercise as opposed to genetically inherited, meaning that dietary change could help prevent diabetes.

Bottom Line: For Natural Weight Loss, Eat Plant-Based and Load Up on Legumes

If losing weight is a goal, shift your protein sources from meat and animal products to whole foods that are plant-based such as vegetables, fruit, whole grains, nuts and seeds, and most of all legumes. Legumes were shown in a recent study to help promote weight loss and a reduction in body fat.

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