As we head into the holiday season and keep an eye on COVID-19 cases this upcoming winter, now is a great time to strengthen our immune systems to combat the virus.

According to Associate Professor of dietetics and nutrition Cristina Palacios, supplements and foods rich in certain vitamins and minerals is crucial.

“Those of us that have a better nutritional status can fight the disease better than others,” says Palacios, a faculty member at the Robert Stempel College of Public Health & Social Work. “We constantly have pathogens, such as viruses and bacteria, coming into our bodies. If our immune system is working well, we don’t get infected.”

She adds, “In general, nutrition affects our entire body. All body processes require enzymes, and many vitamins and minerals help enzymes work better. There’s the saying, ‘We are what we eat.’ It’s true. If you want to be healthy, you have to consume particular nutrients.”

So, how do we keep our immune systems healthy during this time?

To shed light on the matter, Palacios recently hosted a free virtual webinar for the community. The webinar was part of an ongoing series organized by Palacios and a team of graduate students to share information with folks trying to keep their families healthy.

Earlier this year, Palacios collaborated with a team of international experts to develop a guide published in the official journal of the Latin American Society of Nutrition (SLAN) to help frontline workers protect their health through supplements food. During the webinar, Palacios shared some of those recommendations for adults in the general public as cities continue to reopen.

Here are the top three supplements adults should consider taking.

1. Vitamin C. This vitamin has been hailed for years as a go-to source for aiding the immune system. Palacios said vitamin C is vital for leukocytes’ health, a type of white blood cells that help fight infections. It’s particularly important during a pandemic. She recommends adults take a supplement of 1000 mg twice every day.

She also recommended consuming foods rich in vitamin C. These foods include the classics of orange juice and oranges as well as other citric fruits and vegetables, including grapefruit, strawberries, tomatoes, and cranberries.

2. Vitamin D. Most often, we get our vitamin D through the sun, but throughout this time, Palacios said, taking a supplement is a good idea. She added that studies have shown that low levels of vitamin D have been associated with a greater risk of developing respiratory conditions in adults and children.

In fact, studies have begun to show that people with vitamin D deficiencies are at a higher risk of getting infected by the COVID-19 virus. The time to act is now.

Palacios recommended adults take a supplement of vitamin D3 of 1000 International Units (IU) once or twice per day, consumed during meals.

Additionally, you can boost your vitamin D intake by eating fish and other foods fortified with the vitamin.

For those who have a vitamin D deficiency, consult with your doctor or dietician for an accurate supplement dosage.

3. Zinc. Palacios said that zinc is crucial for the normal development and functioning of cells mediating part of the immune system. She added that studies have shown that increased zinc concentrations can inhibit the replication of viruses like poliovirus and SARS-coronavirus.

She recommended adults take a zinc supplement of 40 mg or less once a day.

Nutrients through food

Palacios recommended adults work several other nutrients into their diet through foods. While the following nutrients have not been proved to help in the fight against COVID-19, they boost the immune system in general, so consuming them through foods is the way to go.

Vitamin A. Palacios recommended consuming the vitamin through foods including milk, dairy products, and eggs, as well as orange and yellow fruits.

Vitamin B3 (Niacin). This vitamin helps the immune system by reducing inflammation and damage to the lungs, said Palacios. Foods high in Vitamin B3 include chicken, meats, fish, grains, beans, legumes, and nuts.

Vitamin B9 (folate and folic acid) – studies have shown this vitamin can prevent respiratory infections in children, Palacios said. You can consume foods with folate in leafy greens like spinach and folic acid in fortified foods, including pasta and bread.

Probiotics – Palacios added that certain strains of probiotics in specific situations could prevent upper respiratory tract infections. You can find probiotics in yogurt and fermented milk.