Since the virus that causes COVID is so new, relatively speaking, prospective studies on the link between nutrients and COVID outcomes are limited. In this rare prospective study on COVID patients that were hospitalized, researchers found that over half of the patients were zinc deficient, and those with lower zinc tended to have worse outcomes.
A prospective study is one in which two groups of patients are monitored over time for a certain outcome and some variable (zinc in this case) is compared between the groups. In this study, the outcomes recorded were the following: complications of COVID, respiratory distress, steroid therapy, prolonged hospital stay or death. (This is different than a retrospective study, in which patient history is reviewed and a doctor is looking at past health history trying to link it to some present outcome.)
Doctors measured fasting zinc levels in the blood when the patients were initially hospitalized. Then, after monitoring these patients and correlating their zinc levels, they noted that the risk for COVID complications was significantly higher in zinc-deficient patients. Healthy patients and zinc-deficient patients both presented clinically in the same manner with fever and cough, and subsequent symptoms of body aches, sore throat and gastrointestinal issues were also the same in patients with normal and deficient zinc. Finally, the COVID patients did differ much on any underlying conditions, regardless of whether they had normal or deficient zinc. So, at the beginning of their illness, both groups (normal and zinc-deficient) fared similarly.
But after time, the patients who were zinc deficient experienced more complications than those with normal zinc levels. Remember – all the patients were hospitalized for COVID so whether or not they had good zinc, they were still succumbing to COVID. Yet, it is after time in the hospital that the disparity between normal and zinc-deficient patients emerged. For example, in the COVID patients with normal zinc, none of them died. But 18% of the COVID patients with zinc deficiency died. Similarly, in the normal zinc group, only 10% of the patients went to the Intensive Care Unit (ICU) while 25% of the zinc-deficient patients went to the ICU.
It is impossible to know whether zinc deficiency caused worse outcomes, or if worse outcomes exacerbated zinc deficiency. In fact, the answer may be a combination of both. It is well established that zinc has very strong anti-viral effects and is a key cofactor in regulating the immune system response.
Zinc is also necessary for immune cells to properly mature, particularly in the development and activation of T-cells, which research shows are a key player in successfully fighting COVID and establishing lasting immunity against SARS-CoV-2.
Deficiency in zinc has long been associated with immune system dysfunction and susceptibility to viral infection.
Because zinc in involved in well over 100 biochemical reactions in the body, the exact mechanism of action is hard to know and they almost certainly overlap. This study is simply a reminder that nutrient status is more important than ever in fighting COVID.
SpectraCell Laboratories measures zinc status (plus 30 other nutrients) in its Micronutrient Test.
(International Journal of Infectious Diseases, September 2020)
LINK to FREE FULL TEXT COVID-19: Poor outcomes in patients with zinc deficiency.