If you’re struggling to lose weight, could chilling your carbs help?

Online influencers say the secret to low-calorie rice, pasta and potatoes could be as simple as relaxing.

Are they right? Not quite. But a small but solid body of science suggests that refrigerating these high-carb foods after cooking them could help people lose weight.

For several years, wellness and nutrition influencers have promoted a process called downshifting, urging people to cook, cool, then reheat high-carb foods. They say it can reduce calories.

Downshifting is real, but it’s not that simple.

Most of the carbohydrates in these foods – as well as most of the calories – come from starch, of which there are two types: hard-to-digest amylose and easy-to-digest amylopectin. The latter is treated quickly and raises blood sugar levels. The first is processed slowly and moderates blood sugar levels.

Most raw carbohydrates (think uncooked potatoes) are primarily made up of hard-to-digest starch (also called resistant starch), but cooking converts them to easily digestible starch. This is why diabetics should be careful when eating starchy foods.

This is where influencers get excited. Cooling these cooked foods triggers “retrogradation,” a process that converts easily digested starch back to resistant starch, making it more difficult to digest even if the food is subsequently reheated.

What does this mean for calories and blood sugar? Here’s what we know:

Studies on how retrogradation influences diet have been limited and have focused on how consumption of resistant starches influences blood sugar levels, particularly in diabetics.

Several studies since 2015 have shown that people who ate cooked and then cooled rice sometimes had significantly lower blood sugar levels after eating compared to people who ate freshly cooked rice. These results are generally well accepted.

Less studied is whether downshifting also reduces the calories available in these foods.

Sort of, says Dr. David Ludwig, an endocrinologist and researcher at Boston Children’s Hospital. “It doesn’t noticeably change the calorie content of that food,” he explained. “(But) it could very well affect your hormones and metabolism in a way that makes calorie control much easier.”

Although the effects of downshifting on calories are neither as direct nor as dramatic as some suggest, they still show promise as part of a healthier diet, Ludwig said.

Eating foods high in resistant starch reduces the rise in blood sugar typically seen after eating cooked carbohydrates, he explained. And it’s not just essential for diabetics.

Studies have shown that these sugar spikes activate the brain’s reward mechanism and trigger cravings, making it more likely to overeat during subsequent snacks and meals.

Additionally, these blood sugar spikes increase the body’s production of insulin, which not only makes us hungry but also triggers the body’s metabolism to store more calories as fat, Ludwig said.

“When food retrogrades, it digests more slowly,” he said. “This will keep your blood sugar more stable. You’ll have less insulin to store fat, and you’ll likely have an easier time avoiding overeating.”

If you eat a diet high in refined starches, refrigeration can technically alleviate some of their negative impacts. But Dr. Walter Willett, professor of epidemiology and nutrition at the Harvard TH Chan School of Public Health, says that to be effective it would need to be done consistently, and he questions whether it’s practical for most people.

It’s not simple plug-and-play either. Downshifting works better with some grain varieties than others. For example, some food manufacturers favor rice varieties that are naturally low in resistant starch because they cook more quickly. But this information is rarely available to the consumer, so it’s difficult to know when cooling makes a difference.

Willett also noted that downshifting only helps blunt the effects of blood sugar.

“Chilling does not restore the losses of fiber, minerals and vitamins that were removed in the refining process,” he said.

Better, he says, to keep it simple: substitute minimally processed whole grains, cooked as you normally would.

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JM Hirsch is a food and travel journalist and former food editor for the Associated Press.