What nutrients are important for immunity?

 

Several vitamins and minerals have integral roles in maintaining a healthy immune system. A few of the key players and their sources include:

• Vitamin A (beta carotene) – orange fruits and vegetables, cooked spinach

• Vitamin B6 – chickpeas, salmon, chicken/turkey, banana

• Vitamin B12 – animal-based foods, supplements

• Vitamin C – red/green pepper, orange, grapefruit, kiwi, broccoli, Brussel sprouts, strawberries, cantaloupe

• Vitamin D – few dietary sources provide adequate vitamin D; obtain through supplements

• Vitamin E – wheat germ oil, sunflower seeds, almonds, sunflower/safflower oil, peanut butter

• Zinc – oysters, animal protein, baked beans, pumpkin seeds, cashews, hemp seeds, wheat germ

• Folate – cooked spinach, black-eyed peas, asparagus, Brussel sprouts, lettuce, avocado, broccoli

• Magnesium – nuts, seeds, whole grains, leafy green vegetables

• Selenium – the best source is Brazil nuts. Limit to max 4 per day

 

In general, healthy people are advised to meet the recommended intake for each of these nutrients through diet (you can use Cronometer to track your intake of each of these nutrients), rather than supplements. However, the International Society for Immunonutrition (ISIN) recommends that the elderly achieve much higher levels of certain nutrients due to the decline in immunity that accompanies the aging process.

 

Recommendations from the ISIN are as follows:

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• Vitamin E (134 mg - 800 mg/day)

• Zinc (30 mg - 220 mg/day)

• Vitamin C (200 mg - 2 g/day)

• Vitamin D (2000IU - 4000 IU/day)

 

If you are not elderly, and struggle to meet the recommended intakes of immune-boosting nutrients, you may wish to supplement with the following (higher doses should be discussed with your physician first):

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• Vitamin D: 2000-4000 IU per day

• Vitamin C: 500 -2000 mg per day

• Zinc: 40 mg/day

• Magnesium: 200 mg/day

 

Again, it’s important to emphasize that research on COVID-19/Coronovirus is just emerging and few, if any, studies have been rigorously peer-reviewed. The following information is based on previously published literature form unrelated trials:

 

Vitamin C

Routine supplementation of 50 mg to 2000 mg may reduce the incidence of pneumonia and duration/severity of the common cold.

Zinc

Zinc acetate taken at a dose > 75 mg after the onset of a cold may reduce its duration.

Herbal supplements

North American ginseng (200 mg 2x per day for 4 months) will not prevent acute respiratory infections but may shorten their duration.

Probiotics

Some evidence exists to suggest that probiotics can reduce the incidence and duration of respiratory tract infections, but there is lack of evidence to recommend a particular strain, dose, or route of administration.

Others

Increase foods that can have an anti-inflammatory effect like Ginger, Garlic, Raw Honey, Turmeric, and Cinnamon.

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Are there any food safety concerns I should be aware of?

 

For a detailed review on food safety and the COVID-19/Coronavirus, check out J. Kenji López-Alt’s fantastic article.

As mentioned, there is no data to suggest that COVID-19/Coronavirus spreads through food. However, practicing food safety is still important for preventing foodborne illness and mitigating the transfer of the virus. It may be advisable to shop at smaller grocery stores, outside of peak hours, in order to limit contact with others. Be careful not to touch your face while shopping and upon arriving home, transfer foods to clean containers and/or sanitize the package. If you’re at all worried of the presence of COVID-19/Coronavirus in your food, remember that heating food (outside layer) to 149°F (65°C) for at least 3 minutes can destroy the virus. And most importantly, don’t forget to wash your hands before, during, and after cooking and handling food!

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