During the past decade, vitamin D (in reality, a hormone) has been in the news more so than any other vitamin out there. Its deficiency has been touted as the reason for dozens of human health problems, ranging from rickets to osteoporosis to teeth loss to depression to cancer to high blood pressure to multiple sclerosis. However, for most such problems, there is insufficient evidence that a vitamin D deficiency caused the condition in the first place. Nor is there concrete evidence that vitamin D supplementation causes any significant improvements in most such health problems.
Having said that, there are some conditions (e.g., rickets and other bone problems) where prolonged vitamin D deficiency has been proven to have a strong causative effect, and a number of other conditions where there is some evidence of the importance of a sufficient intake of vitamin D. As is the case with most vitamins and minerals, deficiencies are usually far more dangerous in early childhood than in adulthood.
Types of Vitamin D
There are five types of vitamin D, known simply as D1, D2, D3, D4 and D5. Of these five, the two major forms are D2 (ergocalciferol) and D3 (cholecalciferol). When doctors talk about vitamin D, they generally mean D2 or D3 or both (collectively referred to as calciferol). Direct sunlight exposure is the easiest way to raise one’s vitamin D levels, since the skin synthesizes vitamin D upon exposure to ultraviolet rays (US). Numerous food items naturally contain vitamin D, and many are artificially enhanced with the addition of vitamin D in developed countries.
Optimal Vitamin D Levels
Modern life is heavily indoor-focused, with daytime computer based work followed by evening time entertainment and social media related screen-time for most people. Not to mention 24/7 smartphone access, usually also indoors or in shady areas to avoid sun glare. This has drastically reduced direct sunlight exposure in just one generation, and sunlight has historically been the best way for most of us to get vitamin D. Moreover, daily warnings about skin cancer and skin aging have meant that even when outdoors, most people lather on sunscreen and suntan lotion, drastically limiting vitamin D synthesis via the skin. Moreover, if you are mostly getting your daily sunshine through office windows or car windows, it does not raise your vitamin D levels since glass prevents UV rays from synthesizing vitamin D on your skin.
Because of all the above, most readers must have heard a lot in recent years about the huge number of people who are vitamin D deficient and the potential dangers of this problem. In fact in a radio show just last week, I heard that some scientists think that the current cutoff levels are too low, and if corrected, around 80 percent of Americans are vitamin D deficient (although this is a controversial issue). Quite often, people who are warning about this issue are also selling vitamin D supplements, so one must be vary about the messenger.
There is significant debate about ideal levels of vitamin D (i.e., what number seems to be the best for overall health) as well as about insufficient levels of vitamin D (i.e., below what number does it become dangerous for your health). The most common measurement for vitamin D is done via a blood test known 25-hydroxyvitamin D, with resulting numbers given in ng/mL (for those outside the US, just multiply these numbers by 2.5 to get corresponding numbers in nmol/L).
Most doctors consider that levels below 20 ng/mL are insufficient. Many nowadays have raised this number and consider levels below 30 ng/mL to be insufficient.
Ideal levels are even more heavily debated, with some data suggesting as high as 70 ng/mL, but other data suggesting that over 50 ng/mL can even be dangerous. Yet other data suggests that anything over 30 ng/mL does not lead to any benefits.
Trying to find and analyze all the main (probably 100 plus by now) studies here about this subject matter would be way beyond the scope of this blog. Moreover, your genetics, race, sex, height, weight and more can also impact the ideal levels for you. I am happy if my levels are over 20 ng/mL, which they are not in winters (so I supplement).
Vitamin D and Hair Loss
Over the years, I have read numerous comments from people suggesting that vitamin D has an impact on hair loss and growth. However, while researching for this post, I found that even some respected scientists have postulated this theory and a WSJ article in 2012 looked at this subject in detail.
- Per the above article, the leading researcher in this field seems to be Dr. Marie Demay, a professor at Harvard Medical School. According to her, the vitamin D receptor (VDR) activates hair growth, rather than the vitamin itself. The Demay lab continues to do research on the vitamin D receptor and hair growth (plus keratinocyte stem cells). Their latest study related to this subject matter came out in March of 2017, and is titled: “Absence of vitamin D receptor (VDR)-mediated PPARγ suppression causes alopecia in VDR-null mice“. I will not try to analyze that.
- Also important, in 2012, a research team led by Dr. Yuko Oda at UCSF found that knocking out (ablating) the transcriptional coactivator mediator (MED1, in particular) in mice led to increased hair growth.
- And finally, a team from Japan led by Dr. Kotaro Yoshimura and Dr. Noriyuki Aoi published an important study in 2012 that found that vitamin D3 promotes functional differentiation of dermal papilla cells (DPCs) and “could be useful in preserving the hair follicle-inductive capacity of cultured DPCs for hair regeneration therapies”. Apparently this could also help improve hair transplantation results.
- A 2016 study from Egypt found lower serum and tissue VDR levels in patients with AA and AGA in comparison to those with neither form of hair loss.
Miscellaneous Notes
- Some hair loss products that I have seen over the years have included vitamin D as one of the ingredients, but I highly doubt that this makes much of a difference in regrowing lost hair.
- It should be noted that even if you take or have taken vitamin D supplements orally, for many people (including myself), it sometimes requires mega doses (upwards of 20,000 IU per day, at least initially) to have any significant impact on one’s vitamin D blood test readings. Some doctors will not prescribe that much due to potential side effects, although as yet, I do not think this danger has been proven.
- I seem to have better hair when I am out in the sun a lot. I am certain this is not psychological. How about you? Like plants, I think that humans need sufficient levels of sunshine and water (and oxygen too for humans) in order to thrive.
- It is interesting that low-level laser therapy (LLLT) has been shown to benefit hair growth in a number of studies, and the average wavelength of light from LLLT devices is in the 600nm-900nm range. UV rays from the sun fall in the 300nm-400nm wavelength range.
- In most scenarios where things such as vitamins, minerals, growth factors and so forth are involved, it seems like women tend to benefit more than men. This is based on my general intuition from what I have read over the years. Male hormones are usually the predominant reason for men’s hair loss, but other factors are often more important for women. I would not be surprised that if vitamin D does benefit hair, it will be more effective in women than in men.
- Sunlight also seems to kill mites and improve other scalp problems for many people.
- An interesting study from Hungary suggests that androgenetic alopecia might have been an evolutionary mechanism to protect men from advanced prostate cancer since a bare scalp enhances UV ray absorption in the scalp. And apparently increased UV radiation reduces the risk of prostate cancer. Not sure about this. Men who suffer from AGA are more likely to have prostate cancer…so according to this theory, they would be even more likely to have prostate cancer if they had all their hair intact.
Thanks to Mr. BB
I had considered writing this post in the past, but put in on the backurner until I recently got two e-mails from a person I will address as “Mr. BB”. They spurred me to discuss this subject. I am pasting most of his two e-mails’ content below:
E-mail 1:
I found this page and thought it could be of interest for you as you also follow closely the AA. It´s dated from February 2017:
https://www.vitamindcouncil. org/new-study-finds- derivative-of-activated- vitamin-d-helps-manage-hair- loss/
I am taking vitamin D3 supplement since 14th of April 2017 and must say that within 3 or 4 days (not weeks or months) I noticed the hair stopped falling. I even think my hair is growing back in some places. The doses I take are important. In fact today I am taking 30000 UI daily (Thirty Thousand).
I started to lose my hair around 1992-1993. It´s been a slow process but it has reached a level that made me think I´d better shave it all. Until I found some study on Vitamin D3 and started to supplement myself. I think it is working…
It´s already a miracle that something could make your hair loss stop let alone something that makes them regrow and boosts thickness and growth. What if the cure has always been here and it was just of Vitamin D deficiency ? In countries in which we live in (Europe, North America) it has been proven that 80 % of population is Vitamin D deficient.
By the way Vitamin D3 is not a Vitamin it is a Hormone and is said to enter in the expression of about 200 genes among which is the synthesis of a natural antibiotic that fights against the seasonal flu (influenza).
E-mail 2 after I sent him a brief reply:
There is something that I have heard about vitamin D3 from a specialist who even wrote a book about it.
That guy was saying that they discovered that French are Magnesium Chloride deficient. And guess what ? Magnesium Chloride is a cofactor to the vitamin D. Meaning that you they need to go hand in hand if you want to see benefits with vitamin D. Magnesium Chloride is the key !
I was on Magnesium chloride since 22nd of March 2017. And taking only that stopped my spring allergy and breathing problems. I am taking about 200 ml of magnesium chloride a day. That´s 100 ml after each meal.
Few weeks later as I saw my health was improving I started also to take vitamin C. I dilute about 5 g of Vitamin C powder in my 100 ml magnesium preparation.
Than I started vitamin D on the easter weekend with just 4000 UI and before the weekend was over I noticed the hair stopped falling.