Want to fight off infectious diseases this winter? Consider boosting your immune system with nutritious food.
“What we eat is very important in terms of how our immune system responds to pathogens and how well it can defend itself against a pathogen,” said Dr. Simin Meydani, senior scientist and leader of the nutritional immunology team at Tufts University’s Jean Mayer USDA Human Nutrition Research Center on Aging.
Micronutrients such as vitamin C, vitamin D, vitamin B complex, zinc and selenium can help “pump up” the body’s defenses against colds, flu and even Covid-19, Meydani said, but you won’t boost immunity by “eating a large amount of one single nutrient or food component.”
Forget focusing on “superfoods.” A large variety of foods are needed to provide the micronutrients the body needs to mount a robust cellular immune response, said Stanford School of Medicine nutrition scientist Christopher Gardner.
“There isn’t any one food or nutrient to rely on here, but rather it is the interplay of ‘harmonious interactions’ between the various micronutrients,” Gardner said.
Plan your daily menus around a large variety of fresh and colorful red, yellow, orange, blue and green fruits and vegetables, along with some high-quality whole grains, a bit of lean protein and a splash of healthy oils.
A wide variety of colorful foods is also the basis of the top-rated Mediterranean diet and DASH diet, which stands for “dietary approaches to stop hypertension,” or high blood pressure.
Numerous studies found the Mediterranean diet can reduce the risk for high cholesterol, dementia, memory loss, depression and breast cancer. Meals from the sunny Mediterranean region have also been linked to stronger bones, a healthier heart and longer life. Oh, and weight loss, too.
An overall picture
Just how much you can jump-start immunity with nutrients depends on your age, overall health and stress levels, according to Meydani.
In addition to eating well, it’s important to stay at a healthy weight, reduce your stress, get quality sleep and regular exercise to keep those natural defenses in fighting shape. Without that healthy baseline, your body will have to work harder to knock out invaders – and may even lose the match.
“The best defense against the acute threat of the coronavirus is chronically good health,” said Dr. David Katz, founder and president of the True Health Initiative, a nonprofit dedicated to promoting evidence-based lifestyle medicine.
“If you encounter the virus a week from now, two weeks from now, three weeks from now, there is a chance you will do better because of what you do with your diet right now,” he said.
Pump up the volume
If you want to maximize the impact of food on your immune system, you’ll need to dramatically increase the amount of fruits and vegetables you eat each day, Meydani says.
Her team investigated immune responses in animals fed two to three servings of fruits and veggies a day, and compared them to those who ate five to six servings a day or eight to nine servings a day.
“The eight to nine servings a day was where we were seeing the best effect,” Meydani said. “So it’s not just increasing the intake by a little bit, you’ve got to increase it substantially. People need to work at it in order to reach that level.”
Finding ways to insert fruits and veggies into every meal and snack during the day may do more than pump up your immunity. A 2017 study found a significant reduction in the risk of heart attack, stroke, cancer and early death by eating 10 portions of fruit and vegetables each day.