Recently we have been getting asked a lot about vitamin D testing at the clinic. I first became interested in vitamin D 3 years ago because of the research that was coming out of the States. We have done over 800 vitamin D blood tests at the clinic and have been surprised how many of our women are deficient. Also, let’s not forget the research showing that Vitamin D is important for men.
We are now able to offer clients a vitamin D blood test at the clinic. There is increasing evidence to show the importance of vitamin D for a number of functions in the body, including fertility and pregnancy.
What is Vitamin D?
Vitamin D can be classified as both a vitamin and a fat-soluble pro-hormone. Its metabolic product, calcitriol, is actually a secosteroid hormone that targets over 1000 genes in the human body. It is needed for many functions in the body and new research is showing that many people are deficient in vitamin D
What is the natural source of Vitamin D?
Vitamin D is obtained naturally from two sources: sunlight and food. It is, however, found in few foods and we get most of our Vitamin D from the action of sunlight on our skin. Natural food sources of vitamin D include eggs and oily fish such as herring, salmon, mackerel, sardines and tuna. Some foods such as breakfast cereals are fortified with vitamin D. Compared with our ancestors, we spend a lot more time indoors, wear more clothes and use sunscreen which lowers the skin’s ability to form vitamin D by more than 95%. Darker skinned people require at least five times as much sun exposure to form a given amount of vitamin D compared with lighter-skinned people. Low levels of Vitamin D are a particular problem in winter when there is less natural exposure to sunlight.
Reasons for considering being tested:
o Ovulatory problems and PCOS – In a study of 67 women with anovulatory infertility, 93% of women were deficient in Vitamin D. Supplementing with vitamin D helps to restore normal ovulatory function.[1] Vitamin D deficiency was highly prevalent amongst women with PCOS. Supplementation (alongside calcium) normalises irregular periods.
o IVF failure – particularly if failing at implantation stage, may be due to Immune issues. Deficiency of vitamin D is common among people with inflammatory and autoimmune disorders ranging from rheumatoid arthritis to multiple sclerosis. This may be relevant for women with IVF failure.
o Miscarriage – Vitamin D deficiency is linked to miscarriage. It also increases the risk of pre-eclampsia by five-fold.[2]
o Pregnancy – Supplementing with Vitamin D may enhance the immune function of the placenta and protect it from infection.[3]
o Diabetes – low vitamin D status is associated with insulin resistance and has been linked with an increased risk of Type 2 diabetes.
o Steroids – use of corticosteroids has been found to reduce the activation of vitamin D.
o Weight control – obesity is associated with a higher risk of vitamin D deficiency.
o Depression – Seasonal affective disorder (SAD) is linked to limited sunshine exposure and vitamin D supplementation significantly improves mood within days.
o Migraine headaches – supplementation of calcium and vitamin D in vitamin D deficient women has been shown to reduce frequency, duration and severity of menstrual migraine attacks[4]
Current research has implicated vitamin D deficiency as a major factor in the pathology of at least 17 forms of cancer as well as heart disease, stroke, hypertension, autoimmune diseases, type 1 diabetes, depression, schizophrenia, chronic pain, rickets, osteoarthritis, osteoporosis, muscle weakness, muscle wasting, birth defects, periodontal disease, and more. Vitamin D deficiency in early pregnancy has been described as an ongoing epidemic and mounting animal research on gestational vitamin D deficiency and its possible effects on the fetus leads some scientists to recommend that pregnant women – or women thinking of becoming pregnant – should have their vitamin D levels checked about every three months.
How do I take the Vitamin D test?
The Vitamin D blood test can be arranged through the clinic and costs £42. When the result comes back you will be contacted with a recommendation of the vitamin D dose to supplement with. We also advise a repeat test after 3 months on the supplements
1 Rebecca Smith in the Telegraph 11 Nov 2008, reporting on ASRM conference – Pal J. Yale University – Vitamin D insufficiency in reproductive years may be contributory to ovulatory infertility and PCOS.
2 Bodnar L, et.al. Maternal Vitamin D Deficiency Increases the Risk for Preeclampsia, Journal of Clinic Endocrinology & Metabolism 2007Vol 92, No. 9: 3517-3522
3 Liu, N, et al., Vitamin D induces innate antibacterial responses in human trophoblasts via an intracrine pathway, Biology of Reproduction Dec 2008. doi: 10.1095/biolreprod.108.073577
4 Vasquez A, The Clinical Importance of Vitamin D (Cholecalciferol): A paradigm shift with implications for all healthcare providers, Alternative therapies, Sept/Oct 2004, Vol 10. No 5: 28-36