The Best Diet for Immune Health, According to Nutritionists

By Candace Nagy

February 23, 2023

The immune system is a complex network of organs, cells, and chemicals that work together to protect our bodies from disease and infection. It can even recognize and remove harmful germs from our bodies, as well as prevent diseases through its memory-like, adaptive immunity response. So it should come as no surprise that maintaining a healthy immune system is key in protecting our overall health: The stronger it is, the healthier we are.

There’s been a recent spike in brands touting immune-boosting supplements — many of which seem like snake oil. While scientifically-proven supplements can definitely play a positive role in the health of many people, the truth is that optimal nutrition is arguably more important for achieving a strong immune system. After talking with five nutritionists, we discovered that the best diet for immune health really is rooted in smart food choices — and we found some great recommendations for helping you stay healthy and keep your immune system up.

“While there’s no magic food that can prevent you from getting sick, a nutrient-dense diet can help immune defenses function their best,” says Jackie Bertoldo MPH, RDN, lecturer at Stanford University. “It’s also well-documented that deficiencies of certain nutrients, like vitamin A, vitamin E, and zinc, can suppress immune function and increase the likelihood of infection.”

The top foods (and micronutrients) necessary for optimal immune health

So, what specific foods can we aim to include in our diets that take these expert recommendations into account? One of the largest food groups to look towards are whole, preferably raw, fruits and vegetables. When planning meals, it’s helpful to step back and look at them over the course of a week: You want to make sure that you’re eating a wide variety of healthy foods. Most of us have probably heard of the term “eat the rainbow,” and that’s a good rule of thumb to follow. Some that stand out for their high levels of vitamins A, C, D, and E — important for immune health — include leafy greens (kale, spinach), red bell pepper, and papaya.

1. Blueberries and other vitamin C sources

“One of my favorite foods to snack on is blueberries. They’re extremely high in antioxidants which support our immune system,” says Mackenzie Burgess, RDN at Cheerful Choices. “Blueberries are also a great source of important nutrients like fiber, potassium, and vitamin C. Other rich sources of vitamin C include kiwis, berries, and bell peppers.”

2. Lean proteins

In addition to fruits and vegetables, a large portion of the micronutrients — essential vitamins and minerals — that play a crucial role in immune health are found in lean proteins. “Good sources of protein for immune health include yogurt with live and active cultures, nuts and seeds (vitamin E), poultry for its vitamin B6, and shellfish, which contains zinc,” says LeeAnn Weintraub, MPH, RD .

“The optimal diet for immune health contains enough protein to support healthy body functions,” says Atlanta-based nutritionist Allie Echeverria, MS. “Amino acids are the building blocks of protein. When we eat protein, our bodies break it down into amino acids, using them to grow and repair themselves. Protein plays an important role in healing and recovery.”

3. Anti-inflammatory spices

“There are some foods that are important to note for their anti-inflammatory role in immune health,” Weintraub says. “These include ginger, turmeric, and garlic, all of which contain a variety of antioxidants and immune-boosting properties.”

4. Healthy fats

In the 1990s, we thought that being healthy meant avoiding fats — which turned out to be an absolute bunk. While it’s true that it’s healthier for you to avoid trans fats like partially hydrogenated vegetable oil, healthy fats are excellent for your immune system. Sources of good fats like nuts, olive oil, avocados, salmon, and sardines contribute positively to the health of our immune systems.

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The best diets for immune health

There are endless combinations of foods that can make up a healthy diet, and everyone’s body is different, so it’s difficult to pin down any specific option from the growing list of categorized diets, like paleo and keto. However, there are two popular diets that particularly stand out due to their inclusion of foods from a variety of healthy food groups — and the limitation of those that are highly processed or contain artificial preservatives.

The Mediterranean Diet

The Mediterranean is home to two of the world’s official “Blue Zones,” or locations where people have been found to be among the healthiest and live the longest. They’re both islands: Sardinia, Italy, and Ikaria, Greece. Sure, the fact that a large number of people living in these areas experience long, healthy lives can be attributed to their overall commitment to exercise and stress-reducing techniques — not to mention the gorgeous weather and ambiance — but their diet is undoubtedly one of the greatest contributing factors.

“If I absolutely had to put a name to an overall healthy diet, it would be the Mediterranean diet, as it’s rich in a variety of whole grains, fruits and vegetables, protein, and healthy fats,” says Nussbaum. Foods at the forefront of the Mediterranean diet are leafy greens, fatty fish, and beans — all quality immune boosters.

A plant-based diet

When we think of plant-based diets, we may think of an exclusively vegetarian or vegan diet — which can be great for your immune system, too. But in a wider sense of the term, this diet can simply mean consciously making foods from plant sources a major part of our diets and including them at every meal.

Whether we’re following a vegan, vegetarian, or omnivorous plant-based diet, it’s important to take into account modifications that may be necessary in ensuring that our bodies absorb the nutrients needed to function properly. “Vitamin C increases iron absorption from plant sources,” Echeverria says. “This is especially important for people who follow vegetarian or vegan diets. A spinach salad with sliced oranges or lentils with bell peppers are examples that combine the two nutrients.” (And check out our recent story on food combining for more info.)

Are supplements important for immune health?

Generally, for those with no underlying health issues or conditions that require modified diets, all the nutritional support that our bodies need can be found within whole foods. “You don’t actually want to boost your immune system too much. Diseases associated with an overactive immune system are not pleasant — ask anyone suffering from lupus, psoriasis, or rheumatoid arthritis. Those diseases, and others, are similar in that the immune system attacks the body’s own tissues,” says Ilisa Nussbaum, MPH, RDN, clinical dietitian nutritionist at the Yale New Haven Hospital. “There is no quality evidence that products like alkaline water, essential oils, colloidal silver, or elderberry have any impact on the immune system. At best, it’s a waste of your money. At worst, you could be doing more harm than good.”