Vitamin A was allegedly once called “ “the anti-infective vitamin” — a snappy title which didn’t stick with any biochem student beyond the end of the sentence.
But it’s needed for your immune system to function normally, so it seems sort of obvious to ask “what if” we don’t have enough. Could taking more prevent people catching Covid or ending up in hospital, or dead?
As always, research in prevention and prophylaxis is a wasteland in the the Modern West. No one can profit from it and indeed if everyone got enough it could harm the prospects of shareholders of Pharmaceutical firms and Hospitals.
But it appears we definitely don’t want to be short of it. About three quarters of people who end up in the severe ward of Covid hospitals were deficient. …
Vitamin A makes our bones stronger, reduces wrinkles, may prevent cancer and stops us going blind. But it’s possible to eat too much — especially if we dine out on polar bear livers or sled dogs. Seriously, overdosing for pregnant women causes birth defects and trouble for anyone who really overdoes it.
Signs of Vitamin A deficiency include dry skin, eczema, dry eyes, night blindness, infertility, chest infections, poor wound healing, and acne. Though all of these can be caused by other things too. People who are anaemic and people with inflammatory bowel disease, fibrosis, liver trouble or pancreatitis are more likely to be deficient.
Our white blood cells that catch some booty (like body-parts of germs) will turn up to show it off, and when they do they’ll ooze versions of Vitamin A which induces other immune cells to respond to their prize and mature and proliferate.
Vitamin A also manages to mobilize iron stocks to fill up the haemoglobulin molecules in baby red blood cells, something that makes them both red, and useful. It’s easy to imagine how extra red blood cells, and thus oxygen carrying capacity might be handy when dealing with a disease notorious for inducing low blood oxygen.
Vitamin A comes in meat, eggs and milk, but precursors (the carotenes) are found in leafy and colorful vegetables like spinach and carrots, so even vegetarians, in theory, ought to be getting enough of the building blocks so their livers can finish the job.
But a study in Spain showed that the sickest people with Covid were often the ones that were deficient. Three quarters of those admitted to hospital were deficient in zinc and Vitamin D, but nearly as many, 72%, were deficient in Vitamin A. And 42% were low in B6 …
The problem with that kind of study is that we can’t be sure that the disease didn’t create the deficiency, and that the sickest people drained away their A and zinc in the process of getting sick. But from other studies we already know that Vitamin A is anti-inflammatory, as well as helping promote immunity. … And that backing up a truck and giving super massive doses of 200,000IU to Covid patients appeared to save about two thirds of them from ending up with a severe disease. …
Naturally, there aren’t many big good definitive studies in the West. We throw billions at patentable experiments, and our public universities, but no one is that interested in the ten-cent-nutrients that might reduce deaths by half. Though one large prospective study in the UK followed 15,000 people and found people taking Vitamin A and selenium supplements were quite a lot less likely to get a positive Covid result — odds were reduced by about 60% and 80%. …
The RDA for adults is around 700 ug/day (women) and 900 ug/day (men). (That’s 2,333IU, and 3,000 IU). It’s worth being tested before embarking on a long term supplement program, but otherwise, having a bottle on hand for respiratory infections and short term dosing is probably a good idea.
A similar story with vitamin D.
Is the profit motive killing us? Seems like there is a pretty good case.