There are things about respiratory viruses that we can’t control, such as this season’s flu strain, the effectiveness of the flu vaccine or if the person sitting behind you at a restaurant is covering their cough.
And with cold and flu season well underway, it’s important to take action to prevent these illnesses in ways you can control: washing your hands frequently and minimizing barehand contact of public surfaces such as doorknobs and handrails, and so on.
Another thing you can control: your diet pattern.
After all, the immune system can’t work at maximum capacity if you are deficient in nutrients.
The good news is that the diet recommendations that keep our immune systems in optimal condition are the same recommendations for an overall healthy diet.
So, if you needed another reason to eat healthier this year, there it is.
For a strong immune system, make sure you are getting these micronutrients (Mayo Clinic, 2025):
- Iron: Needed for immune cell efficiency. Foods like red meat, beans, nuts and fortified cereals are good sources of iron.
- Vitamin A: Shields us from infections by keeping skin and tissue healthy. Orange and red fruits and vegetables, such as carrots and bell peppers, have high levels of Vitamin A.
- Vitamin C: Promotes the creation of antibodies and the function of white blood cells. Found in strawberries, tomatoes and citrus fruits.
- Vitamin D: Activates immune defenses and plays a role in your body’s ability to effectively fight off bacteria and viruses. Found in fatty fish, egg yolks, fortified dairy and sunlight.
- Vitamin E: An antioxidant that defends cell membranes from free radical damage. Seeds, nuts, peanut butter and some oils have this vitamin.
- Zinc: Supports immune cells’ function and development, and maintains skin barriers for fighting off bacteria and viruses. Foods such as meats, seeds, nuts and whole grains are good sources.
What about supplements?
You get more health benefits when your nutrient intake is from food sources, such as fiber, antioxidants and phytochemicals.
Nutrients are also more potent and are absorbed better from food versus supplements.
Fat-soluble vitamins, which are D, E, A and K, need fat for absorption, and won’t provide as many benefits if taken as a supplement without a meal or food source with dietary fat.
It’s important to note that taking supplements in conjunction with eating an unhealthy diet isn’t going to cancel out the risks that come with poor eating habits.
Supplements should complement a healthy diet, not replace it.
If you are eating a healthy balanced diet, then you are likely getting enough vitamins and minerals, but getting blood work at your annual checkup will give you a bigger picture of your nutrient levels and finding out what you may be deficient in.
If your diet falls short (such as vegan diets lacking Vitamin B12), or you’re of a certain population (such as older age where it’s hard to absorb some nutrients, or pregnant women, who have more nutritional demands), then make sure you discuss with your provider about taking supplements.
Shari Bresin is the Family & Consumer Science Agent for the University of Florida/Institute of Food and Agricultural Sciences Cooperative Extension Pasco County, An Equal Opportunity Institution.