Vitamin D is a fantastic fat-soluble vitamin that helps prevent cancer, increase bone health and can even prevent heart attacks. You can get vitamin D from supplementation or naturally from sun exposure.
However, if you live in the northern hemisphere, you probably don’t ever get enough vitamin D. This is because both Vitamin D supplements and the sun aren’t as popular north of the equator.
Thus, is becomes imperative to supplement with vitamin D whenever possible.
Vitamin D has been linked to internal cancer prevention. One study in 2008 showed that those with adequate amounts of sun exposure (usually five to ten minutes a day for at least three days a week) are less likely to develop any type of internal cancers (1).
This is because the vitamin D that we obtain from sunlight works in our bodies to help regulate calcium flow and build us up from the inside out.
Another study from the European Journal Of Cancer Prevention had similar conclusions (4).
Vitamin D boosts bone health in post-menopausal women. It has been shown that vitamin D plays an extensive role in strengthening the bones of postmenopausal women. Studies by dominant women’s health organizations have provided a link between vitamin D and a reduction in the hip fractures of senior women (5).
Vitamin D can reduce the risk of death. A study in 2011 found that the likelihood of mortality was decreased by 7% by those who supplemented with vitamin D, then those who did not (6).
Vitamin D can reduce the risk of multiple sclerosis. There are now links between adequate vitamin D sufficiency and a reduction in the likelihood of contracting autoimmune disorders, such as multiple sclerosis, or MS. A 2006 study in the Journal of the American Medical Association suggested that adequate levels of Vitamin D decreased the risk of developing MS (7).
Another study in 2014 showed that adequate vitamin d may slow the progression of multiple sclerosis for those who already have it (8).
Vitamin D supplementation can prevent type I and type II diabetes. Diabetes has become somewhat of an epidemic globally. Vitamin D supplementation to battle it. A study of 10,921 infants, followed since the day of birth, revealed that those who supplemented with 2.000 IU per day of vitamin D had a 78% lower risk of developing type I diabetes (9).
Another 2011 study in the European Journal of Clinical Nutrition found that vitamin D supplementation is linked to a reduced risk of adult-onset (type II) diabetes (10).
However, it should not be taken as a cure-all, as the links between vitamin D and diabetes are still not wholly proven. Furthermore, it is too much of a simplification to suggest that adequate levels of vitamin D are all that is required to prevent diabetes. Instead, a whole list of measures should be taken in order to maintain proper health.
Vitamin D can prevent heart disease and heart attacks. A study in 2008 showed that low levels of vitamin D are associated with a higher risk of myocardial infarction – even if all other lifestyle factors are perfectly in line with decreasing the likelihood of heart attacks (11).
Another study in 2008 concluded that Vitamin D deficiency is associated with increased incidents of cardiovascular disease (12).
Vitamin D boosts the immune system and prevents the flu. As if all of these significant health benefits to adequate vitamin D intake were not enough, studies suggest that there are increasingly more and varied health benefits to vitamin D.
One of these is the prevention of viral and bacterial infections that can make us sick and prove severely damaging to our health, such as coming down with a cold. By working in our bodies on a cellular level, studies suggest, vitamin D helps our immune systems stay strong against external threats.
One study in 2010 showed that vitamin D3 supplementation during the winter may reduce the incidence of influenza A, especially in specific subgroups of schoolchildren (13).
Another 2011 study showed that low levels of vitamin D were correlated with increased respiratory illnesses (14).
Vitamin D can reduce fractures and strengthen bones. There has long been an established link between the intake of vitamin D and a reduction of bone disease. This is because vitamin D manages the calcium in our bodies that strengthen our bones and allow us to maintain mobility (14).
One study in 2005 showed that adequate (800 IU/day) vitamin D supplementation reduced the risk of hip and any nonvertebral fractures in ambulatory or institutionalized elderly persons. An oral vitamin D dose of 400 IU/day is not sufficient for fracture prevention (15).
Vitamin D can increase coordination and reduce falls. A 2007 study showed that Nursing home residents who supplemented with 800 IU of vitamin D per day had a lower number of fallers and a lower incidence rate of falls over 5 months than those taking lower doses (16).
Vitamin D can boost brain health to prevent dementia and Alzheimer’s. A 2014 study published in the American Academy of Neurology found that low levels of vitamin D were correlated with a 53% increase in developing dementia a 70% increase in developing Alzheimer’s (17).
What’s even scarier is that people with a severe vitamin D deficiency (which is not uncommon in the northern hemisphere) led to a 125% increase in the likelihood of developing dementia.
Vitamin D may help fight depression. It’s no secret that many people suffer from a mild depression during the winter months. A 2013 study showed that low levels of vitamin D were directly correlated with depression and the likelihood of developing depression (18).
Furthermore, a 2008 study showed that adequate vitamin D supplementation reduced the symptoms of depression in adults (19).
Vitamin D increases muscular strength. A 2017 study done by researchers at the University of Birmingham concluded that higher levels of vitamin D were correlated with an increase in muscular strength (20).
Vitamin D can help promote weight loss. A 2008 study out of Cambridge University showed that participants who supplemented with vitamin D were able to lose more weight than a placebo group (21).
Vitamin D may help deal with irritable bowel syndrome. A 2018 study noticed a link between low levels of vitamin D and IBS symptoms. It seems that increasing vitamin D supplementation among those with IBS help ease the problem (22).
However, much more testing needs to be done to confirm.
Vitamin D can help reduce acne. Acne can be caused by a variety of factors, one of them being bacterial overgrowth. If this is the case for you, vitamin D supplementation can reduce symptoms of acne due to its antimicrobial properties (23).
A 2014 study also showed that low levels of vitamin D were correlated with increased severity of acne symptoms.
Vitamin D can prevent hair loss and even restore hair growth. A 2012 study concluded that hair loss was correlated with low levels of vitamin D. It has also been shown that vitamin D can help promote hair growth by increasing follicle production (24).
Vitamin D can boost energy. A study in 2010 published in the Journal of Clinical Sleep Medicine confirmed a link between low blood level vitamin D and tiredness (25).
When the woman in the study increased her vitamin D supplementation, her hyper-insomnia symptoms disappeared.
Vitamin D can reduce back pain. A 2006 study showed the correlation between back pain and vitamin D deficiency (26).
Vitamin D can improve overall body healing. A 2011 study found that patients who had low levels of vitamin D experienced longer recoveries after their dental surgery than those who didn’t (27).
Another test tube study published in 2016 found that vitamin D increases the production of wound healing properties in the body (28).
One more study found that low levels of vitamin D were correlated with high inflammatory markers which were directly linked to poor healing capabilities (29).
Vitamin D can reduce muscle soreness. A study in 2015 was done to determine the effects of vitamin D and pain. 120 children with growth pains were examined. After a single dose of vitamin D, the children reported that pain dropped 57% (30).
Too much vitamin D can cause nausea, vomiting and poor appetite. A 2011 study showed that vitamin D toxicity led to nausea, vomiting and a poor appetite. It was concluded that this was due to high calcium blood levels from the vitamin D toxicity (31).
However, it seems once blood levels are returned to normal, symptoms disappeared.
Vitamin D toxicity has shown to promote bone loss.
One of vitamin K2’s most essential functions is to keep calcium in the bones and out of the blood. This keeps bones healthy and strong. Megadosing on vitamin D has been shown to be correlated with low serum blood levels of vitamin K2 (34).
As a result, bone loss is expedited.
Vitamin D can shut down your kidneys. In 2016, 62 adults were given extreme doses of vitamin D to see its effects on the kidney’s, 100% of them developed kidney failure, even if they had perfectly healthy kidney’s to begin with (35).
Too much sun to get vitamin D can cause burns and potentiate skin cancer. Because of this, it is vital to maintain a proper level of sun exposure (with occasional use of sunscreen) (36).
Despite all this, it’s important to note that vitamin D toxicity is very rare, and only happens if you take very high doses for long periods of time (37).
The RDA by the US government is 400IU for infants, 600IU for persons aged 1-70 and 800IU for adults 70 and older (38).
However, many experts believe that the RDA is way too low, especially for people who aren’t exposed to the sun a lot (39).
According to Institute of Medicine, the safe upper limit is closer to 4,000 IU (40).
As such, 1000-2000 IU per day is recommended.
It’s important to note that nutrients usually don’t work in isolation – especially fat soluble ones. It’s crucial to all be supplementing with vitamin A and K2 when supplementing with vitamin D as they all work synergistically (41).
Q: Which foods are high in vitamin D?
A: Fatty fish such as tuna, salmon, and mackerel, beef liver, cheese and foods that are fortified with vitamin D which usually include orange juice, cereals, and milk.
Q: What is the best way to absorb vitamin D?
A: Sunshine is the best way to get vitamin D, but sunscreen blocks its production. Many people don’t have access to sunshine for most of the year.
Q: Should you take vitamin D in the morning or at night?
A: Because vitamin D temporarily stops the production of melatonin (the sleep hormone), it’s important to take in the morning instead of late at night.
Q: What is the difference between vitamin D2 and vitamin D3?
A: Vitamin D3 (cholecalciferol) is found in some animal foods, like fatty fish and egg yolks. Vitamin D2 (ergocalciferol) is found in some mushrooms. Of the two, D3 (cholecalciferol) is the one we’re interested in, because it is almost twice as effective at increasing blood levels of vitamin D as the D2 form
Q: Is vitamin D fat soluble or water soluble?
A: Vitamin D is one of the fat-soluble vitamins (A, D, E, and K), meaning that it dissolves in fat/oil and can be stored in the body for a long time. As such, overdosing on vitamin D can build up to toxic levels much faster than overdosing with water-soluble vitamins.
Q: Why is vitamin D called a steroid hormone?
A: Vitamin D is turned into calcidiol, the storage form of the vitamin, which is then converted into calcitriol, the active steroid form. Calcitriol binds to the vitamin D receptor inside cells, turning genes on or off.
Q: Other than the sun, which is the best source of vitamin D?
A: Cod fish liver oil is the single best source of vitamin D3. Fatty fish is also a good source, but you have to eat it very often to get enough.
Q: Is vitamin D deficiency a problem?
A: Yes, it is well known to cause rickets in children. However, more research shows that long-term vitamin D deficiency has many other detrimental effects throughout the entire body.
While its free to get vitamin D from the sun, more than likely if you live in a place north of the hemisphere, you are deficient (at least for part of the year). Thus its worth your money to invest in a reliable vitamin D supplement.
That being said, there are many proposed health benefits to vitamin D intake, but these should not be taken as magical cures for a wide array of health problems. Instead, individuals should be aware of their health and the steps they may be able to take to prevent future health-related issues. Remember: a supplement is supposed to support your health efforts not do all the work for you.