Good news for anyone considering going plant-based: A new study finds that switching to a low-fat plant-based diet can rev metabolism and lead to weight loss, as well as lower lipid levels and create a healthier insulin response to food -- so you burn calories rather than store them as fat.

The new study was recently published in JAMA. The findings show that a low-fat diet will turn up your metabolism, which makes it a viable alternative to losing weight and keeping it off, as opposed to the strategy of the keto diet which is a low-carb diet that is nearly impossible to stay on for long, requires a high amount of fat, and is often associated with eating processed meat, which has been linked to a higher risk of heart disease, cancer and chronic inflammation.

This flies in the face of all the keto dieters out there, who try to eat as few carbs as possible and instead choose to eat more fat and protein. The 16-week trial is one of the first to use actual dietary intervention to reduce body weight in overweight adults, rather than study the less reliable self-reporting by large swaths of the population who answer questions from researchers on what they eat.


The 16-week randomized clinical trial found that "low-fat plant-based dietary intervention reduced body weight by reducing energy intake and increasing postprandial metabolism" or how much you burn calories after a meal rather than store energy as fat.

"Meaning: A low-fat plant-based diet is an effective tool for reducing body weight and increasing insulin sensitivity and postprandial metabolism.

The study found that adults with excess body weight and insulin resistance (which can lead to type 2 diabetes and other major health problems) benefited by going on a low-fat plant-based diet.

The study's objective: To measure the effects of a low-fat vegan diet on body weight, insulin resistance, postprandial metabolism, and lipid levels in overweight adults.

The study measured results among 244 people aged 25 to 75 with a body mass index of between 28 to 40. Then 122 people were asked to follow a low-fat vegan diet and the control group of 122 were asked to make no diet changes for 16 weeks.

After 16 weeks, body weight was measured using a calibrated scale. Body composition and visceral fat were measured by a density test while Insulin resistance was assessed with the homeostasis model.  And the thermic effect of food was measured by indirect calorimetry over 3 hours after a standard liquid breakfast in  44 participants.

Over the 16 weeks,  among those eating the low-fat vegan diet, they lost weight, (nearly 6 kg), while their metabolism shot up 14% and their insulin sensitivity improved. Meanwhile, their lipid levels went down by 34.4%, None of these variables changed significantly in the control group.

There reason eating plant-based helps promote weight loss is that "the sources of protein on a plant based diet do not contain cholesterol or animal fat, which can help reduce blood lipids, according to nutritionist and bestselling author, Rania Batayneh, MPH, who wrote The One One One Diet: The Simple 1:1:1 Formula for Fast and Sustained Weight Loss. "When consumed in the proper portions, plant based proteins can have less calories (and fat) than animal proteins. The consumption of less calories can result in weight loss. A plant  based diet is also higher in fiber," she adds, "which helps to promote stabilized blood sugar levels which helps you mange hunger and cravings.

If losing weight is the goal, sign up for The VegStart Diet, which is a 14 day meal plan complete with recipes, expert tips and online support. The 108 page ebook is ready for immediate download here.

Bottom Line:  Going on a low-fat plant-based diet reduces body weight by reducing energy intake and increasing metabolism after eating. The changes are associated with reductions in blood lipid levels and healthy increased insulin sensitivity.

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