Your grandmother was right: In the summer, you should eat lighter fare, like salads, and leave the heartier stews and soups for winter. Doing so could help us lead healthier lives – and possibly also lose a few pounds, a top expert says.

“We should be eating according to the seasons. We’ve known this since Paleolithic times, but over the past 60 years, we lost sight of it,” John Douillard tells Newsmax Health.

“The season of summer is the best season to transition to a healthier diet,” says Douillard, author of the book, “The Three Season Diet.”

“If we aren’t careful, the foods we eat during the summer can affect our bodies and digestion through Thanksgiving and beyond.”

Doulliard’s book is based on the concept that we should eat according to the three growing seasons –– spring, summer and fall, a nutritional system based on Ayurveda, the traditional Hindu system of medicine. 

“The idea behind eating for three seasons has its roots in ancient times but there is new science – related to the microbiome – that backs this up,” he explains.

Research is increasingly finding that our microbiome, which are thousands of microbes, both inside and on our bodies, influence the way our body functions.

“New research suggests that our gut microbes change seasonally, depending on the foods that we eat,” says Douillard, a chiropractor and certified addictions counselor. “Seasonal microbes optimize digestion, mood and immunity – the way nature intended,” he adds.

On the other hand, in the spring, the weather turns rainy and muddy, so fruits and vegetables that grow during this season are easier on the stomach.

“We’re apt to get congested then, so nature sends us a low-fat harvest of sprouts, as well as fruits and vegetables, foods that are easier to digest,” Doulliard notes.

“Spicy foods, like ginger and turmeric roots, are also more available in the spring. These pungent foods are really good in the wet season because they are decongesting.”

Summertime brings water-rich fruits and veggies that are appetizing during warm-weather months.

“In the summer, nature gives us cooling foods like watermelon, apples and pomegranates, to help us beat the heat,” Doulliard says.

The fall harvest, he notes, brings foods like fermented foods, such as sauerkraut, cheese and yogurt.

Winter is the dormant season, so it doesn’t figure into the three growing seasons concept, but there are foods you should eat during this season as well, he says.

“In the winter, nature provides a harvest of bountiful nuts, seeds, and grains,” Douillard notes, adding that our body also produces more amylase, an enzyme that helps us digest starch. “This suggests our digestive system amps up.”

Here are Douillard’s five tips on how to eat seasonally:

• Incorporate wheat into your diet wisely. Wheat, which is harvested in late summer and fall, stores well and can be eaten in winter as whole-grain bread or warming gruel. The enzyme in our body that breaks down wheat, amylase, increases in our body in fall and winter, and decreases in the spring and summer, which suggests that much less wheat should be eaten during those times. Whenever you do eat wheat, make sure it’s whole grain and unprocessed.

• Save the hearty soups, stews, and heavy foods like meat for winter. Don’t resist eating a hearty stew in the winter, because the microbes in our body are geared to digesting it, in order to keep warm. Also that afore-mentioned enzyme, amylase, ramps up your digestion, making it easier for you to digest foods like meat, as well as starches, like the potatoes in that stew.

• Hot, spicy foods don’t mix with summer. If you like spicy foods better get them on the table during the spring when the body is transitioning from the winter. Once summer rolls around it’s best to avoid hot and spicy foods.  Also avoid coffee, red met and eggs, all of which can put undue stress on organs such as the prostate, liver, stomach, and small intestines.

• Eat the chicken, not the egg. While eggs are considered a warm food that should be avoided during summer months, chicken is considered a cool food. This is because chicken, sans the skin, is a lean protein. Egg yolks, on the other hand, are packed with protein, which heats the body up, so they are better to eat in the winter.  

• Drink water before each meal. Staying hydrated is one of the most important things you can do for your body, especially during the summer. Water is the best way to stay hydrated, but it’s best to drink water 15-30 minutes before a meal. Drinking it during a meal will drown out stomach acid, which breaks down hard to digest proteins.