Vitamin D has received a lot of attention in recent years as study after study has shown the different ways that vitamin D deficiency affects our health. The role of vitamin D in bone mineral density is well-established. More recent explorations have found possible links between vitamin D status and immune system regulation, mood, weight management and heart health.

A very high quality review of the current evidence found that supplementing with vitamin D decreased the risk of death by any cause (formally referred to as ‘all-cause mortality’). That is big news. In my opinion, that puts maintaining adequate vitamin D status right up there with the most established health habits: avoiding smoking, and eating lots of fruits and vegetables for example.

Of the many effects of vitamin D deficiency, some relate directly to fertility: normal production of sex hormones, frequency of menstrual periods in women with polycystic ovarian syndrome and sperm quality/quantity to name a few.

In a time when delaying having babies is the norm, it is good to know that higher vitamin D levels are associated with lower FSH levels, which may mean that having adequate vitamin D delays the end of our fertile years.

Looking beyond conceiving a baby, good vitamin D status may reduce the risk of adverse outcomes in pregnancy and allow the growing baby to have enough vitamin D for his/her growth and development.

Vitamin D should not be taken without having your blood level checked. Sun exposure, digestive system health, genetic factors, body mass index and dietary intake can all affect your vitamin D level so it is best not to make any assumptions about your current level. Having too high a vitamin D level comes with its own risks, so please monitor your vitamin D level and supplement with the help of a medical doctor, nurse practitioner or naturopathic doctor.

Dr. Andrea Hilborn is a naturopathic doctor in Kingston, Ontario

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