Published on January 16, 2023

Give Your Immunity a Leg Up

Ariel Rearick, MS, RD


While vaccines are a proven first line of defense, we can implement a one-two punch approach and reinforce our natural defense system with a diet rich in vitamins and minerals. Including foods in your daily routine that are packed with the following nutrients may improve your overall health and resistance to illness.

Vitamin C: A diet rich in vitamin C aids the body’s natural defenses and may prevent viruses from reproducing, making colds shorter and less miserable. Stick to 2,000 milligrams or less daily to avoid side effects like diarrhea, nausea, and stomach cramps. Food sources include: citrus fruits, broccoli, brussels sprouts, red and green bell peppers. 

Vitamin D: People with low levels of the so-called “sunshine vitamin” are more prone to infections, from flu to HIV. About one in four Americans has low vitamin D blood levels. For better absorption, take it with a meal or snack containing fat. Food sources include: fortified dairy and cereals, fatty fish, egg yolks, mushrooms. 

Omega-3 fatty acids: High levels of omega-3s have been linked to decreased inflammation and better immune-cell function. Aim for 2 grams or less per day. Food sources include: fatty fish, chia and flax seeds, walnuts.

Zinc: This essential mineral lowers inflammation and keeps immune cells in fighting shape. However, more than 40 milligrams per day may cause nausea, vomiting, and headaches. Food sources include: oysters, beef, chicken, pork loin, fortified cereal, pumpkin seeds, baked beans. 

Supplements do not have to be researched or regulated to be sold. Because of that, no dietary supplement can be legally marketed as a treatment, prevention, or cure for any disease or condition, including flu, cold, and COVID-19. Food sources are the best way for your body to get vitamins and minerals to ensure that they are well-absorbed and utilized. fortified cereal, pumpkin seeds, baked beans. 

If you choose to take supplements, it’s important to tell your health care provider what you’re using. 


Ariel Rearick is a clinical dietitian with Barton Health. Barton dietitians are available for consultation. Schedule a consultation by calling 530.543.5824. 

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