Super foods to boost your immune system

Looking to prevent colds and flu and keep your immune system strong? Head to your supermarket’s produce aisle. Fruits and vegetables are loaded with immune-boosting vitamins, minerals and other nutrients, often called “antioxidants”. But there’s more: antioxidants may even slow the aging process.

Our bodies need antioxidants to repair cell damage caused by molecular chemical changes as we age. These pesky molecules – often called “free radicals” – can start to break down and damage cells throughout the body. Experts believe free radicals can cause hardening of the arteries, cancer, arthritis and other diseases linked to aging. Fruits and vegetables are your best defense against these age-related conditions.

Sources of Antioxidants in Produce

Most fruits and vegetables are natural sources of vitamins. But those with purple, blue, red, orange and yellow hues are often highest in antioxidants. Be sure to eat a variety of fruits and vegetables from each of the main antioxidant groups listed:

Beta-carotene and other carotenoids: Apricots, asparagus, beets, broccoli, cantaloupe, carrots, corn, green peppers, kale, mangoes, turnip and collard greens, nectarines, peaches, pink grapefruit, pumpkin, squash, spinach, sweet potato, tangerines, tomatoes and watermelon

Vitamin C: Berries, broccoli, Brussels sprouts, cantaloupe, cauliflower, grapefruit, honeydew, kale, kiwi, mangoes, nectarines, orange, papaya, red, green or yellow peppers, snow peas, sweet potato, strawberries and tomatoes

Vitamin E: Broccoli, carrots, chard, mustard and turnip greens, mangoes, nuts, papaya, pumpkin, red peppers, spinach and sunflower seeds

Other antioxidant “super foods” include prunes, apples, raisins, berries, plums, red grapes, alfalfa sprouts, onions, eggplant and beans. Fresh and dried herbs also keep your immune system strong, so keep these spices handy:

• Fresh Herbs: Oregano, sage, peppermint, thyme, lemon balm, marjoram
• Dried Herbs & Spices: Cloves, allspice, cinnamon, rosemary, thyme, marjoram, saffron, oregano, tarragon and basil

Make sure your diet contains enough antioxidants

To maximize their nutritional value, eat fruits and vegetables raw or lightly steamed; don’t overcook or boil.

Don’t care for produce? You can get your recommended daily allowance of antioxidants by taking a multivitamin with minerals. However, you will miss out on other nutrients thought to strengthen the immune system. Researchers have linked health benefits to these complex antioxidants found in fruits and vegetables:

• Quercetin: fights inflammation and may help reduce allergies. Found in apples, onions, teas and red wines.
• Luteolin: also fights inflammation and may help protect against inflammatory brain conditions like Alzheimer’s. Found in celery and green peppers.
• Catechins: may help reduce risk of heart disease, cancer and Alzheimer’s disease. Found in tea.

So the next time you head to the grocery store or farmers’ market, fill your cart with fresh fruits and vegetables. Your body will thank you.

Heather Klug is a registered dietitian and cardiac educator at the Karen Yontz Women’s Cardiac Awareness Center inside Aurora St. Luke’s Medical Center in Milwaukee, WI.