Two recent papers have been published recently that seem to support that vitamin D does something to prevent or treat COVID-19. Except for a tiny little problem – both of the studies terribly weak and are unconvincing except to those who just want supplements to do something to end this pandemic. Don’t get your hopes too high.
Of course, the COVID-19 pandemic has caused interest in vitamin D to skyrocket, because there has been a belief that vitamin D improves the immune system against the disease. The sales of vitamin D supplements have increased substantially since pre-pandemic times.
But is there any evidence supporting its use to prevent COVID-19 or improve outcomes for serious cases? Yes, there is evidence, but it’s far from convincing. There are better ways to prevent a COVID-19 infection, and vitamin D is not one of them.
The internet was flooded recently with reports that vitamin D for coronavirus may be either a treatment or prevention. Or it may reduce the severity of COVID-19.
But what does the real data say? Does it say that there is a solid benefit of vitamin D for coronavirus? Is there strong evidence that it can help prevent or treat COVID-19?
The answer is complicated. This is why I am annoyed by science journalists – they don’t critically analyze the underlying science published in peer-reviewed journals. It’s almost like the whole hydroxychloroquine fiasco – latch onto weak evidence and make outlandish claims.
The claims about the usefulness of vitamin D supplements are all over the internet. And they seem trendy, as most pseudoscientific claims are these days.
The purpose of this article is to review some of the old and new information about vitamin D supplements. It’s about scientific articles that either support or refute a claim, that’s it. It’s not about what we believe or we do not believe, it’s about evidence.
I don’t think vitamin D is worthless. It is an important micronutrient for human health, and if there’s a chronic deficiency, supplementation may be medically necessary.
As a vaccine supporter, I get accused of being a shill for Big Pharma all the time. My basement is filled with gold bars shipped to me in remuneration for my services to the corporate hooligans – wait. No basement, no gold bars. On the other hand, Big Supplement, those companies who make money off of people who think that if they take this one vitamin to prevent all cancer, makes a a ton of money selling this junk medicine to unwary and unsophisticated consumers.
Let’s take a moment and look at the differences between Big Pharma and Big Supplement. The former has to work hard and provide evidence of what its drugs do, while the latter basically can sit around and throw darts at various claims, then randomly assign those claims to some new or old supplement.
Lots of people take vitamin D supplements to keep their bones strong as they age, advice that is pushed by legitimate organizations, like the National Osteoporosis Foundation. But does vitamin D actually do anything, or are their effects some kind of myth?
The researchers determined that vitamin D supplements did not usually increase bone density for people who already had normal levels of vitamin D. Although bone density did improve in the femur, the longest and heaviest bone in the human skeleton, all other bones did not exhibit a higher density after vitamin D.
The systematic review included 23 previously published studies (comprising a total of 4082 participants, 92% women, average age 59 years) who received vitamin D supplementation over an average of 23.5 months. Bone mineral density was measured at one to five sites (lumbar vertebrae, femoral neck, total hip, trochanter, total body, or forearm) in each study.
The studies included in the review had differing vitamin D supplementation regimens. The vitamin D dosages, as well as the length of the treatment, varied across. On average, 500 IU (international unit, with each unit being the biological equivalent of 0.025 μg cholecalciferol/ergocalciferol) was the daily dose in six of the studies, 500-799 IU was used in four studies, and 800 IU or more was used in 13 studies.
Across all of the studies, 70 tests of statistical significance were performed. Of the 70, six had findings of significant benefit of vitamin D supplementation, two showed significant detriment, and the rest, 62, show no significant benefit or detriment. Of all the studies, only one showed a benefit at more than one bone site. And more supplementation did not show any benefit, so there was not a dose-reponse effect.
Most importantly, of the studies that did report improvement in bone density, the finding was not significant enough to prevent a bone from fracturing after a fall. Surprisingly, the researchers also discovered that doses of less than 800 IU per day were more effective for improving bone density in the spine.
The researchers concluded that “continuing widespread use of vitamin D for osteoporosis prevention in community-dwelling adults without specific risk factors for vitamin D deficiency seems to be inappropriate.” In other words, the evidence does not support the hypothesis taking vitamin D provided a benefit of increased bone density in individuals who already had healthy levels of vitamin D–supplementing with vitamin D was not necessary for most adults over the age of 55. Moreover, the researchers recommended that healthcare providers should target individuals who may not be getting sufficient vitamin D naturally, such as through exposure to sunlight, with either vitamin D supplementation or sunlight therapy.
To answer the original question? Yes, vitamin D supplementation is a waste of money, unless there specific issues that would indicate that it would be useful, such as in individuals who do not make sufficient vitamin D naturally. And no, more vitamin D does not help.
Vitamin D is a group of fat-soluble steroid-like biochemicals that have one known responsibility in human health–enhancing intestinal absorption of calcium and phosphate, minerals which are necessary for bone development and bone health. In humans, the most important D vitamins are vitamin D3 and vitamin D2, both of which can be ingested from dietary sources, including fishes, milk products, and many other foods. However, the body can synthesize vitamin D’s in the skin when exposure to sunlight is adequate. Because humans can produce their own vitamin D, it is not strictly considered an essential dietary vitamin, which are vitamins that cannot be synthesized in sufficient quantities by an organism, and must be obtained from its diet.
Even though supplementation is necessary for people who aren’t receiving adequate levels of vitamin D through either sun exposure or diet, excessive intake of the vitamin causes a condition called hypervitaminosis D. Excessive vitamin D can lead to acute problems, like excess thirst or increased urination, but over a long-term can lead to heart disease and other chronic conditions.
Other than eliminating direct risks, are there things that can be done to actually prevent “cancer”? Once again, with over 200 types of cancer, this may be an impossibility, but the three most popular cancer prevention ideas are diet, vitamins and other types of nutritional supplements. Vitamins and other supplements are a $61 billion industry in the US. They generate these sales with minimal regulation, minimal quality control over the quality and dosage, and no requirement to actually provide evidence that the supplements do what is claimed by the supplement industry, aka Big Herbal. The FDA only gets involved with the industry if there’s some dangerous side effect, or when the claims of the industry are so outrageous that the FDA has no choice but to get involved.
Potential causes for cancer are numerous. Infections. Radon gas. Cigarette smoking. Sun exposure.Obesity. With over 200 types of cancer, each with a different pathophysiology, there may be an equal (and probably greater) number of causes. Although many causes can be easily eliminated, such as stopping smoking, testing your house for radon, getting an HPV vaccine to prevent human papillomavirus infections, and wearing sunblock to reduce the risk of melanomas, the sheer complexity and number of types of cancer means that there is probably not going to be any simple panacea to preventing (or even curing) cancer. In fact, some hereditary cancers, such as those individuals who carry genes that are implicated in breast and ovarian cancers, may not be preventable at all.
Other than eliminating direct risks, are there things that can be done to actually prevent “cancer”? Once again, with over 200 types of cancer, this may be an impossibility, but the two most popular cancer prevention ideas are supplements and nutrition. Vitamins and other supplements are a $61 billion industry in the US. They generate these sales with minimal regulation, minimal quality control over the quality and dosage, and no requirement to actually provide evidence that the supplements do what is claimed by the supplement industry, aka Big Herbal. The FDA only gets involved with the industry if there’s some dangerous side effect, or when the claims of the industry are so outrageous that the FDA has no choice but to get involved. Continue reading “Folic acid supplements and cancer–myth vs. science”
Potential causes for cancer are numerous. Infections. Radon gas. Cigarette smoking. Sun exposure.Obesity. With over 200 types of cancer, each with a different pathophysiology, there may be an equal (and probably greater) number of causes for “cancer.” Although many causes of cancer can be easily avoided, such as stopping smoking, testing your house for radon, getting an HPV vaccine to prevent human papillomavirus infections, and wearing sunblock to reduce the risk of melanomas, the sheer complexity and number of types of cancer means that there is probably not going to be any simple panacea to preventing (or even curing) cancer.
I’ve never been a fan of vitamin supplements. Aside from a very few supplements intended for a few specific clinical conditions, like vitamin C and scurvy, they have little use in preventing or treating diseases. In fact, because mammalian physiology has evolved a homeostasis for these chemicals, any excess amount that can’t be stored in the fat or other tissue is cleared by the kidneys and becomes part of your urine. I’m willing to venture that the urine of many Americans is quite expensive, with all of the cleared vitamins and other micronutrients. A balanced diet over several weeks is sufficient to provide the body with all of the nutrients and vitamins to be healthy and strong. You are not even required to have all vitamins and nutrients every day, as storage of a few nutrients will be released as necessary, and clinical manifestations of nutrient deficiency may take weeks or months.