Vitamin D- The sunshine vitamin
With winter in full swing, it’s an important time to discuss Vitamin D levels. Vitamin D deficiency is a worldwide epidemic, with well known impacts on calcium metabolism and bone health, but increasingly recognized associations with chronic health problems such as bowel and colonic cancer, arthritis, diabetes and cardiovascular disease. An estimated 30-50%  of the population has low vitamin D3 levels, and these levels decline over the colder months with less exposure to sunlight. Vitamin D is tested via a blood test of 25-hydroxyvitamin D (25(OH)D), and normal levels are defined as 20-31 ng/mL or 75 nmol/L) .
A growing body of evidence shows that vitamin D plays a crucial role in disease prevention and maintaining optimal health.
Sources of Vitamin D: Where can I get Vitamin D?
Ample sunlight exposure is your main source of vitamin D, especially UVB wavelengths. Once you get the proper amount of sunlight, your body will stop producing vitamin D because of its self-regulating mechanism.
Here are other important factors in safe sunlight exposure:
- Time: – Best time to expose yourself to the sun is as near to solar noon as possible (around 1 pm). UVB rays, are very low in the morning and evening, and are abundant during midday – around 10:00 am to 2:00 pm.
- Skin pigmentation – Fair-skinned people can potentially max out their vitamin D production in just 10 to 20 minutes, or when their skin has turned the lightest shade of pink. However, if you have darker skin, you likely need to remain in the sun longer.
- Sunscreen: Don’t put sun screen for the 10-20 min when you are trying to absorb vitamin D
- Sensitive body parts – Arms, shoulders and legs should be exposed but protect your face and eyes.
Vitamin D is only naturally present in a few foods (Beef liver, cheese, egg yolks, cod liver oil and Fatty fish like tuna, mackerel, and salmon), and added to other foods (like some dairy products, orange juice, soy milk, and cereals).
Who is at risk of low Vitamin D levels?
People who tend to be at risk of developing low Vitamin D levels include:
- Breastfed infants
- Older adults
- People with limited sun exposure: those that work inside, work at night time, and those who fully cover themselves when outside
- Those with darker skin
What are some of the effects of low Vitamin D levels?
- Vitamin D plays an important role in bone formation, and low Vitamin D can play a role in the development of rickets in children and osteomalacia in adults. Together with calcium, vitamin D also helps protect older adults from osteoporosis.
- Delayed tissue healing in animal studies 
- Increased risk of bowel and colonic cancer [5, 6]
- Increased risk of diabetes [5, 6]
- Increased risk of arthritis [5, 6]
- Increased risk of cardiovascular disease [5, 6]
- Increased risk of upper respiratory tract infections 
- Increased risk of depression [5, 6]
What about Vitamin D in athletes and active individuals?
The high prevalence seen in the general population of vitamin D deficiency also extends to the elite athlete population. Numerous studies have identified vitamin D deficiency in the adolescent and adult athlete populations. This is especially a problem for athletes who have limited sun exposure because of geography and limited seasonal UVB exposure. It can also be a problem for athletes who use excessive sunscreen and patients with dark skin pigmentation.
Current evidence suggests that the treatment of athletes who are vitamin D deficient may help to improve their athletic performance and prevent injuries.[3, 8]
Vitamin D supplementation
Due to the reduced amount of sunlight and “outside” time in Victoria many people are Vitamin D deficient and may need to supplement. It is very, very important to have your blood levels of vitamin D tested before and during supplementation.
What you need to know about Vitamin D supplements
- Common types of vitamin D supplementation are vitamin D2 and D3. Compared to D2, vitamin D3 is 87 percent more effective, and is the preferred form for addressing insufficient levels of vitamin D.
- The quality of the vitamin D supplement you take is vital. Things you need to consider are;
- What conditions has it been stored in? Being exposed to high temperatures, humidity, air or light are factors that may affect the quality of vitamin D.
- Is the vitamin D in a specialised antioxidant oil base to enhance its stability and absorption?
- Has it been tested using real time stability testing, to ensure it stays fresh right up until the expiry date?
- Has it been tested to ensure it’s free from the presence of contaminants to guarantee you are getting the purest quality supplement?
- What your body requires is vitamin D3 and not vitamin D2, the synthetic form commonly prescribed by physicians. One microgram of vitamin D3 or 25-hydroxyvitamin D3 is about five times more potent in raising serum 25(OH)D than an equivalent amount of vitamin D2. Aside from being less effective, vitamin D2 can also pose potential harm to your body.
Metagenics Liquid Vitamin D3 1000IU is stocked at Chiropractic Solutions and is an excellent product of the highest quality. The advantages of supplementing in liquid form include: better absorption, easier to administer high doses and cheaper than tablet form (vs Osteolan or caltrate).
- Hamilton, B., Vitamin D and Athletic Performance: The Potential Role of Muscle. Asian Journal of Sports Medicine, 2011. 2(4): p. 211-219.
- Lee, J.H., et al., Vitamin D Deficiency: An Important, Common, and Easily Treatable Cardiovascular Risk Factor? Journal of the American College of Cardiology, 2008. 52(24): p. 1949-1956.
- Angeline, M.E., et al., The Effects of Vitamin D Deficiency in Athletes. Am J Sports Med, 2013. 41(2): p. 461-464.
- Angeline, M.E., et al., Effect of Diet-Induced Vitamin D Deficiency on Rotator Cuff Healing in a Rat Model. The American Journal of Sports Medicine, 2014. 42(1): p. 27-34.
- Holick, M.F., Vitamin D: importance in the prevention of cancers, type 1 diabetes, heart disease, and osteoporosis. Am J Clin Nutr, 2004. 79(3): p. 362-71.
- Giovannucci, E., et al., Prospective study of predictors of vitamin D status and cancer incidence and mortality in men. J Natl Cancer Inst, 2006. 98(7): p. 451-9.
- Sabetta, J.R., et al., Serum 25-hydroxyvitamin d and the incidence of acute viral respiratory tract infections in healthy adults. PLoS One, 2010. 5(6): p. e11088.
- Wyon, M.A., et al., The influence of winter vitamin D supplementation on muscle function and injury occurrence in elite ballet dancers: A controlled study. Journal of science and medicine in sport / Sports Medicine Australia, 2014. 17(1): p. 8-12.
- Heaney, R.P., et al., Vitamin D(3) is more potent than vitamin D(2) in humans. J Clin Endocrinol Metab, 2011. 96(3): p. E447-52.