A low-fat, high-carb vegan diet could speed weight loss by increasing the calories you burn after eating, without having to exercise.
Researchers from the Physicians Committee for Responsible Medicine and Yale School of Medicine studied 244 overweight adults during a 16 week diet. Half of the group was randomly assigned to follow a low-fat vegan diet, and was provided with cooking tips. The other half were asked to follow their typical diet without any changes. Both groups kept their exercise habits the same.
By the end of the study, published November 30 in JAMA Network Open, the vegan group had lost an average of 13 pounds as well as a significant amount of body fat. The control group didn't lose a significant amount of weight.
Vegan participants also burned 14% more calories, on average, after meals than before switching diets.
These findings help explain previous studies showing that veganism can be an effective strategy for weight loss, according to Dr. Hana Kahleova, director of clinical research for the Physicians Committee for Responsible Medicine, a nonprofit that advocates for plant-based diets, and lead author of the study.
"We've known for such a long time that a vegan diet helps for weight loss and helps with diabetes but we haven't understood the underlying mechanism, why the vegan diet works,"Kahleova told Insider.
High-fiber plant foods take more energy to digest, boosting metabolism
The calorie-burning boost from vegan diets occurs for several reasons, according to Kahleova. First, vegan diets tend to be filled with whole grains, legumes, and vegetables. As a result, vegans end up eating a lot of fiber, an important nutrient that helps regulate digestion.
Fiber also takes a lot of energy to digest. As the body works to break down fiber, it generates heat, burning calories in the process. This is known as the thermic effect of food.
This could be especially important for older adults. The average age of participants was 53, a time when many people notice a decline in their metabolism and may have a harder time losing weight as a result.
"People think as they age and metabolism slows down, but this shows you can turn things around," Kahleova said.
You can eat carbs and still lose weight
Plant-based foods, particularly when they're unprocessed, contain a lot of complex carbs, which can also boost the thermic effect and increase the number of calories you burn while digesting a meal.
Contrary to the popular myth that carbohydrates cause weight gain, the diet in the study was 75% carbs, 15% protein, and 10% fat.
Participants still lost weight in part due to the thermic effect, but also because all those unprocessed plant carbs are naturally low in calories and high in nutrients. Foods high in fat tend to be more calorie-dense.
Participants in the study weren't asked to restrict calories, but ended up eating an average of 350 calories less each day on a vegan diet.
"Plant based foods are known to be more satiating and less energy dense. This clearly shows that a vegan diet can help people lose weight even without an intent to reduce calories," Kahleova said.
Participants also had plenty of protein on the diet, according to researchers, and supplemented with vitamin B12, an essential nutrient that can be hard to get from plant-based foods.
Vegan diets can also benefit blood sugar levels
By the end of the study, participants also showed improvements to insulin sensitivity, an important factor in maintaining stable blood sugar levels and preventing type 2 diabetes.
That's likely due to the effects of weight loss, according to Kahleova.
"As we gain weight, our body responds less and less to insulin, becoming insulin resistant," Kahleova said.
Too much body fat, particularly visceral fat that accumulates around the organs, can cause health issues, including higher risk of type 2 diabetes.
"The underlying mechanism is buildup of fat," she said. "Think of it like taking a bath. If the bathtub begins to overflow into the living room, thatcan do a lot of damage because it's not built to withstand water. This is kind of what's happening in our cells."
Previous research has also found that vegan and vegetarian diets can help improve blood sugar control even without weight loss, suggesting that high-fiber, plant-based diets have additional benefits.
Kahleova said the next step in this research is studying whether people with type 1 diabetes could also benefit.
Read more:
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FAQs
A low-fat, vegan diet could help with weight loss by speeding up metabolism and naturally reducing calorie intake, according to a new study. Researchers found that participants on the diet burned 14% more calories after meals, since the high-carb, high-fiber meals took more energy to digest.
Does a vegan diet speed up metabolism? ›
Participants on the vegan diet had improved insulin sensitivity, or how easily their body converts sugars into energy. They also had faster post-meal metabolism and reduced fat accumulation inside cells.
Is high-carb low-fat vegan healthy? ›
Benefits of an HCLF Vegan Diet
Whole plant foods are low in calories and offer tons of fiber, so eating them allows you to consume fewer calories and feel fuller, which research has shown can help you lose weight (if that's your goal). Fiber is also great for digestion and for preventing constipation and bloating.
Which is better for weight loss vegan or low-carb? ›
Both keto and plant-based have been shown to help with weight loss and in the short-term, keto wins for overall pounds lost. However, when it comes to fat loss, sustainable weight loss and compliance, nutrient-density, and overall health benefits, a plant-based diet comes out on top.
What are the results of a low-fat vegan diet? ›
Conclusions: A low-fat vegan diet improved body weight, lipid concentrations, and insulin sensitivity, both from baseline and compared with a Mediterranean diet. Blood pressure decreased on both diets, more on the Mediterranean diet.
Can you lose weight on a high carb vegan diet? ›
A low-fat, high-carb vegan diet could speed up your metabolism and boost weight loss, a new study says. A low-fat, vegan diet could help with weight loss by speeding up metabolism and naturally reducing calorie intake, according to a new study.
Does being vegan actually help you lose weight? ›
Generally speaking, vegan diets are associated with a lower calorie intake than other forms of plant-based diets, resulting in more significant weight loss. Lower calorie intake is attributed to plant-based diets with higher fiber content, greater food volume, and lower energy density.
What are the risks of low-carb high-fat diet? ›
If you limit carbs in the long term, it may cause you to have too little of some vitamins or minerals and to have digestive issues. Some health experts think that if you eat large amounts of fat and protein from animal sources, your risk of heart disease or certain cancers may go up.
Can you lose weight on a high carb, low-fat diet? ›
And, as many previous studies have shown, the winning combination was diet and exercise. On average, the low-fat, high-carb group lost 7 pounds. Adding exercise to the same high-carb diet increased weight loss to 11 pounds. By contrast, the high-fat, lower-carb eaters did not lose any weight.
Is a plant-based diet better than high protein for weight loss? ›
Overall, Plant-Based Protein Comes Out on Top
“When it comes to weight loss, it's especially important to be not only having high protein in the diet, but also a high fiber diet,” said Velazquez. “Animal protein is not going to have as high fiber as plant-based proteins.”
5 Habits for Easy Vegan Weight Loss: How I Lost 20 lbs
- Consuming enough vegan protein. ...
- Eat enough Fruit and Vegetables. ...
- Make sure your meals are balanced! ...
- 80/20 Rule. ...
- Create a list of easy vegan recipes.
Keto causes toxic lipid byproducts to accumulate in and kill cancer cells by a process called ferroptosis. This slows tumor growth but also causes early-onset cachexia. When researchers replaced the depleted hormone with a corticosteroid, keto still shrank tumors but didn't kickstart cachexia.
Do low carb diets burn fat? ›
In 2015, National Institutes of Health researcher Kevin Hall found that subjects on a low-carb diet burned less fat (53 grams/day) than those on a low-fat diet (89 grams/day). And in 2016, Hall found that a ketogenic diet did indeed lead to more energy burned but that the small difference didn't correspond to fat loss.
How to lose lower belly fat vegan? ›
Maintaining healthy gut bacteria, getting adequate sleep, reducing stress and eating plenty of fiber all help reduce belly fat. Another key factor is weight loss. Reducing overall calorie intake and increasing exercise significantly helps reduce overall body fat.
Are vegans less likely to be overweight? ›
In multivariate, adjusted logistic regression analyses, self-identified vegans had a significantly lower risk of overweight or obesity [odds ratio (OR) = 0.35; 95% CI: 0.18, 0.69] than did omnivores, as did lactovegetarians (OR = 0.54; 95% CI: 0.35, 0.85) and semivegetarians (OR = 0.52; 95% CI: 0.43, 0.62).
Why are vegans leaner? ›
Lower Caloric Density
Most plant foods are less calorically dense because they typically come packed with fiber and water, which take up more total volume while providing fewer total calories. They also tend to contain less fat, which yields more than double the calories per gram than carbohydrates or protein (9,15).
What happens to your body when you start a vegan diet? ›
At the start of a change to a vegan diet, you could experience a variety of differences to your body. These may include being hungrier, getting gassier, a change in your skin or body odor, weight loss or gain, better or worse sleep, headaches, tiredness, or having more energy.
Do you recover faster on a vegan diet? ›
The reduction in both acute and chronic inflammation reveals why so many plant-based athletes, including those featured in The Game Changers, report reduced DOMS (delayed onset muscle soreness), quicker recovery times after workouts and competitions, faster healing from injuries, reduced tendonitis and joint pain, ...
Does your body detox when you go vegan? ›
This may not be something you want to hear, but with increased amounts of fruits, veg, legumes, and beans, you're likely going to be visiting the bathroom more often than you had before. When you switch to a vegan lifestyle, your body detoxifies itself, which means excreting toxins in alllll the ways.
Do vegans burn more calories? ›
By the end of the study, the plant-based diet group averaged an 18.7% increase in their after-meal calorie burn. They also saw an average weight loss of about 14 pounds (lb). Additionally, the vegan diet group experienced a decrease in insulin resistance and a reduction in body fat.
