#MSCOVID19: vitamin D & zinc

I have already made the case for pwMS to prehabilitate, i.e. to prepare themselves for getting COVID-19. You can read my proposed prehabilitation programme on MS-Selfie. One of the topics I cover is diet and I mention that you should ensure that you are vitamin D (vD) replete. There are three ways to do this. (1) The first is to get a healthy daily exposure to sunshine (~20mins of upper body exposure around midday in summer), which can be difficult if you are disabled and stuck indoors and it is winter where you live. 

(2) Another source of vD is eating foods that are high in vD, for example, fatty fish. However, even the latter is often insufficient to raise your blood levels above 75 or 80 nmol/L, which are the two most common lower levels of normal used by UK laboratories. If you apply evolutionary medicine principles, i.e. what are the vD levels in hunter-gatherers or people who work outdoors,  a level of above 100 nmol/L is probably normal. (3) The easiest way to get above 100nmol/L is with dietary supplements. I have always recommended the Vitamin D Council’s advice which is to take 5,000 U of vD3 per day. I note that the Vitamin D Council’s website has gone offline and I don’t know why. Does anybody know the reason? 

The following small study below from Indonesia shows that low vD levels were associated with a higher chance of dying from COVID-19. As with all studies of this nature, it could be reverse causation, i.e. COVID-19 patients with the greatest level of inflammation in their lungs consumed more vD as part of the inflammatory process. In other words, inflammation caused the low vD levels not the other way round. I am prepared to go as far as saying that in inflammatory or infectious diseases the lower the vD levels the worse the prognosis; this is called the consumptive vD hypothesis of inflammation.

What is needed is a clinical trial to see if vD supplements prevent you from getting severe COVID-19. This type of trial is very difficult as a large number of the population are already taking vD3 supplements and a lot of vD experts will say we don’t have equipoise in that they think people should be vD replete for general health reasons regardless of COVID-19. 

As low dose vD3 supplementation is safe and most of the UK population is vD deficient I would advise taking vD supplements rather than not taking them. Do you agree? 

I am also asked what other supplements should you take? If you have a healthy balanced real food diet you don’t need to take any other supplements. However, if you eat an unbalanced diet for humans, for example, a purely plant-based diet, I would advise you to review your micronutrient intake. While not all vegans have low blood levels of zinc, a recent review showed that vegetarians — and especially vegans — have lower zinc intakes and slightly lower blood levels of zinc than omnivores. I focus on zinc because zinc deficiency is associated with an increased risk of infections and complications of infections. There is also a hypothesis that zinc may act against SARS-CoV-2 at several different points in its replicative cycle (see the article from below) and zinc is also important for anti-bacterial activity. A large number of COVID-19 deaths are due to secondary bacterial pneumonia.

A supplemental dose of 5mg or 10mg per day of zinc should be sufficient with other dietary sources to ensure you are zinc replete. 

In the absence of a SARS-CoV-2 vaccine and an effective antiviral are you ready yet to get COVID-19? If not you need to start today. Prehabilitation is an attempt to lower your chances of getting severe COVID-19 and dying from the complications of COVID-19. If you haven’t please act now!

Vitamin D – the sunshine vitamin

Raharusun et al. Patterns of Covid-19 Mortality and Vitamin D: An Indonesian Study. SSRN April 26, 2020.

This is a retrospective cohort study which included two cohorts (active and expired) of 780 cases with laboratory-confirmed infection of SARS-CoV-2 in Indonesia. Age, sex, co-morbidity, Vitamin D status, and disease outcome (mortality) were extracted from electronic medical records. The aim was to determine patterns of mortality and associated factors, with a special focus on Vitamin D status. Results revealed that majority of the death cases were male and older and had pre-existing condition and below normal Vitamin D serum level. Univariate analysis revealed that older and male cases with pre-existing condition and below normal Vitamin D levels were associated with increasing odds of death. When controlling for age, sex, and comorbidity, Vitamin D status is strongly associated with COVID-19 mortality outcome of cases.

Zinc – an essential micronutrient

Skalny et al. Zinc and Respiratory Tract Infections: Perspectives for COVID‑19. Int J Mol Med. 2020 Apr 14. doi: 10.3892/ijmm.2020.4575.

In view of the emerging COVID‑19 pandemic caused by SARS‑CoV‑2 virus, the search for potential protective and therapeutic antiviral strategies is of particular and urgent interest. Zinc is known to modulate antiviral and antibacterial immunity and regulate inflammatory response. Despite the lack of clinical data, certain indications suggest that modulation of zinc status may be beneficial in COVID‑19. In vitro experiments demonstrate that Zn2+ possesses antiviral activity through inhibition of SARS‑CoV RNA polymerase. This effect may underlie therapeutic efficiency of chloroquine known to act as zinc ionophore. Indirect evidence also indicates that Zn2+ may decrease the activity of angiotensin‑converting enzyme 2 (ACE2), known to be the receptor for SARS‑CoV‑2. Improved antiviral immunity by zinc may also occur through up‑regulation of interferon α production and increasing its antiviral activity. Zinc possesses anti‑inflammatory activity by inhibiting NF‑κB signaling and modulation of regulatory T‑cell functions that may limit the cytokine storm in COVID‑19. Improved Zn status may also reduce the risk of bacterial co‑infection by improving mucociliary clearance and barrier function of the respiratory epithelium, as well as direct antibacterial effects against S. pneumoniae. Zinc status is also tightly associated with risk factors for severe COVID‑19 including ageing, immune deficiency, obesity, diabetes, and atherosclerosis, since these are known risk groups for zinc deficiency. Therefore, Zn may possess protective effect as preventive and adjuvant therapy of COVID‑19 through reducing inflammation, improvement of mucociliary clearance, prevention of ventilator‑induced lung injury, modulation of antiviral and antibacterial immunity. However, further clinical and experimental studies are required.

CoI: multiple