7 Immune-Boosting Foods for People With Diabetes

Protein is essential for strengthening the immune system, as it works with key immune-boosting micronutrients like vitamins A, D, and E, as well as zinc, iron, and selenium, says Julie Cunningham, MPH, RD, a certified diabetes care and education specialist in Hendersonville, North Carolina.

With that in mind, consider the humble chickpea, a plant-based source of protein that is also a powerhouse when it comes to zinc. A ½-cup serving has approximately 1 milligram (mg) of zinc, according to the U.S. Department of Agriculture (USDA), which is about 9 percent of the daily value (DV).

White blood cells need zinc to function, according to a review of research. What’s more, zinc is a boon to the heart, according to one study. That’s important for people with diabetes, because the CDC notes that over time, high blood sugar can negatively affect your heart.

Although chickpeas are high in carbs — a ½-cup serving has about 17.4 g — they’re also an excellent source of fiber, offering 4.8 g, or about 22 percent of the DV per cup, notes the USDA. The latter characteristic makes them ideal for people with diabetes, Cunningham notes.

How to Enjoy Them Cunningham suggests blending chickpeas into a homemade hummus, adding lemon juice, and using nonstarchy veggie sticks, such as celery and bell peppers, instead of crackers for a quick snack.

RELATED: 8 Ways to Manage Type 2 Diabetes and Heart Health

The omega-3 fatty acids found in some types of fish — such as salmon, sardines, herring, and mackerel — enhance the functioning of immune cells, says Erin Palinski-Wade, RD, CDCES, author of 2 Day Diabetes Diet, who is based in Sparta, New Jersey.

Although one research review and meta-analysis found that omega-3s have little or no effect on type 2 diabetes directly, Palinski-Wade says they can have significant benefit when it comes to better immune function. EPA, a component of omega-3s, may enhance the activity of white blood cells, which strengthens the immune benefits, she notes.

How to Enjoy It Oven-baked fish is super simple and very quick, the Food Network notes. Put spices or a tablespoon of fruit salsa on top, along with a splash of lemon or vinegar, and seal the fish in an aluminum foil pouch. Bake at 450 degrees for about 15 minutes, until the fish is flaky.

Vitamin A can help support the immune system through a variety of cellular processes, and one top source is carrots, says Cara Schrager, MPH, RDN, a certified diabetes care and education specialist based in Boston.

“Carrots contain beta-carotene, which is a major source of vitamin A,” she says, so much so that the common garden vegetable actually gave the phytonutrient its name. Furthermore, Schrager says, they contain a low glycemic load, meaning they are unlikely to cause a blood sugar spike.

How to Enjoy Them Schrader suggests grating carrots into tomato sauce or ground meat, or snacking on baby carrots. According to the USDA, about 2/3 of a cup (or 85 g) offers 586 micrograms (mcg) of vitamin A, or about 65 percent of the DV.

RELATED: How to Prepare Veggies When You’re Managing Type 2 Diabetes

Selenium is another important mineral for people with type 2 diabetes, says Cunningham, because it supports thyroid health. According to the American Diabetes Association (ADA), both diabetes and thyroid disease are endocrine issues, so those who grapple with thyroid issues could have a more difficult time with blood glucose control.

Selenium plays a critical role in regulating thyroid hormones, according to the National Institutes of Health. Because research has found that those with diabetes have a higher prevalence of thyroid disorders, it’s helpful to keep your thyroid function up to scratch with good nutrition. Research shows that your thyroid also plays a role in your immunity.

Cunningham recommends a small serving of Brazil nuts to get what you need. According to the Cleveland Clinic, that’s 4 medium-size Brazil nuts (about ½ ounce). In addition to being a single protein serving, the USDA notes that 4 Brazil nuts offer 384 mcg of selenium, or nearly 7 times the DV. That same serving size of Brazil nuts contains only 2.4 g of carbs.

How to Enjoy Them Because it takes so little to get benefits from Brazil nuts, Cunningham suggests including one in your snack rotation, or you can also slice a Brazil nut in thin strips and put it on a salad or over steel-cut oatmeal.

Another important micronutrient is vitamin E, says Schrager, because it’s a powerful antioxidant that helps protect the immune system.

“Walnuts are an excellent source of vitamin E, as well as a great source of omega-3 fatty acids, which help reduce inflammation,” she says. “Walnuts contain very little carbohydrates and therefore have a minimal impact on glucose levels.”

According to the USDA, 1 oz of walnut halves (about 14) offer 0.2 mg of vitamin E, which is about 5 percent of the DV.

Bell peppers are packed with vitamin C, says Schrager, and that helps boost your immune system and eliminate free radicals, which can cause damage to cells. According to the USDA, 1 cup of sliced red bell pepper offers 118 mg of vitamin C, or 130 percent of the DV.

One study involving vitamin C supplements linked the nutrient to improved blood glucose levels in people with type 2 diabetes, and it helped manage blood pressure as well.

“Because bell peppers are a nonstarchy vegetable, they have a minimal effect on glucose levels,” she says.

Another benefit to vitamin C is better skin health and wound healing, because it’s involved with the formation of collagen, according to a report. The ADA notes that diabetes can affect skin, and that skin issues are sometimes the first sign of diabetes.

RELATED: Which Foods Are High in Vitamin C?

Another good source of zinc, lentils are also full of fiber, which helps boost satiety and keeps blood sugar steady, says Schrager. Lentils come in several colors, including brown, green, red, yellow, and black.

“The fiber acts as a prebiotic for healthy gut bacteria,” she adds. “Our gut bacteria has been shown to strengthen our immune system.”

Lentils and legumes (beans) are a great pantry item, dried or canned, she says, and they provide a good amount of protein as well. According to the USDA, ¼ cup of dried lentils contains 30 g of carbs and 15 g of fiber (60 percent of the DV). Lentils are a low-glycemic-index food, making them suitable for people with diabetes.

How to Enjoy Them Lentils are a great add-in for soup, especially because you can put together one that also has numerous types of veggies. For example, they pair well with onions, cauliflower, and bell peppers, as this low-carb recipe from Wholesome Yum demonstrates.

RELATED: What Makes for a Good Type 2 Diabetes Diet?