Nutrition & Immunity

I’ve seen a lot of info floating around about nutrition and immune health.  Of course, the most important thing you can do to avoid infection with the novel coronavirus is to prevent exposure by following the latest recommendations from the CDCand World Health Organization. Some additional measures known to help the immune system function at full capacity include getting adequate sleep and maintaining adequate self-care (eating enough, getting fresh air, engaging in joyful movement, and using helpful stress-reduction methods).

Many supplements and natural or other alternative treatments are being promoted to prevent or treat coronavirus (COVID-19). None have been proven to work, but some have potential benefit to support baseline immune health.

Here’s the latest, courtesy of ConsumerLab.com, an evidence-based consumer watchdog organization whose mission is to identify the best quality health and nutrition products through independent testing:

Vitamin and minerals that can help with coronavirus if you're not getting enough 

• Vitamin C is vital to the function of leukocytes (white blood cells that help to fight infections) and overall immune system health. Vitamin C is also important for iron absorption, and being deficient in iron can make you more vulnerable to infections in general. The recommended daily intake of vitamin C for adults from the diet and/or supplements is 75 to 120 mg. It is easy to get this amount and most people do. You can get about 80 to 90 mg from just a cup of orange juice or sliced orange, or even more from a cup of sweet peppers, tomato juice, or cut kiwi fruit. 

  Taking high-dose vitamin C (e.g., 500 mg twice daily) before getting a cold may slightly reduce the severity and duration of a cold but won't stop one from getting a cold. The evidence is inconclusive as to whether taking vitamin C will help after cold symptoms develop. 

  There is no evidence that getting more than the daily requirement of vitamin C can protect people from infection from coronavirus. Higher intakes of vitamin C may potentially help people who are critically ill with COVID-19 and on ventilators.

  There are side effects and risks associated with taking high doses of vitamin C. People sometimes assume there is no harm in taking large doses because it is water-soluble (i.e. excess vitamin C is excreted from the body), but this is not the case. In addition to causing gastric distress and diarrhea, high doses of vitamin C (over 500 mg per day) over the long-term may increase the risk of cataracts. High-dose vitamin C can also reduce the effectiveness of certain medications and interfere with certain blood tests. 

• Vitamin D supplements, taken daily in moderate doses, may help to reduce the risk of respiratory infections and viruses such as influenza A in children and adults who are deficient (< 20 ng/mL) or severely deficient (< 10 ng/mL) in vitamin D. 

  Although there is not currently any research suggesting vitamin D supplements decrease the risk of coronavirus infection specifically, maintaining an adequate blood level of vitamin D by getting proper sun exposure (at least three times a week for about 30 minutes exposing your hands, arms, legs, and face), consuming vitamin D-fortified products (such as most milks, certain other dairy foods and some plant-based milks), or taking a vitamin D supplement is a good, safe, preventative measure for protecting against respiratory infections in general. Consult with your clinician to determine the right Vitamin D dosage for you. 

• Zinc lozenges or other orally dissolving zinc formulas containing certain forms of zinc have been shown to reduce the severity and duration of colds, which are caused by viruses. They appear to do this by acting directly in the throat, which is why the timing and duration of use matters when treating colds with zinc. The connection with coronavirus and zinc lozenges is that the major cause of illness and death among people who are symptomatic with COVID-19 is respiratory disease and it is in the upper airway that zinc lozenges can have some activity. However, zinc from lozenges will not directly help with lower respiratory illness (i.e., in the lungs), which is of greatest concern in COVID-19, because the dissolved zinc leaves the respiratory system after the throat, moving to the gastrointestinal system. 

  Be aware that typical daily doses of zinc provided by zinc lozenges generally exceed tolerable upper limits for zinc, and for this reason, they should not be used for longer than about a week. Excessive intake of zinc can cause copper deficiency. Zinc can impair the absorption of antibiotics, and use of zinc nasal gels or swabs has been linked to temporary or permanent loss of smell. 

What else have you heard about nutrition and immunity? Schedule a call to discuss your specific needs and concerns and always consult a qualified clinician before starting or changing any regimen.

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