It may come as a revelation that many people here in Australia are Vitamin D deficient even though we reside in a land of year round sunshine. Doctors are becoming increasingly concerned about growing rates of vitamin D deficiency, leading many of them to recommend that people get outdoors more or even take supplements.
Vitamin D has long been known to play an important role in bone health. Deficiency can lead to osteoporosis, diabetes, high blood pressure, ‘stroke’, heart disease, depression, a decrease in body muscle mass, gum disease and certain 
forms of cancer. Sutherland et al (1992) postulates Vitamin D deficiency is linked to the degeneration of Alzheimer’s disease. It has also believed that the potential to develop autoimmune conditions such as alopecia, areata, vitiligo, psoriasis and inflammatory bowel disease also increase with Vitamin D deficiency
If we totally avoid the sun, our bodies require around 4,000 International Units (IU) or 100 micrograms of Vitamin D per day. Approximately 20-30 minutes of strong sunlight on bare, non-sun screened skin will produce approximately 20,000 IU of Vitamin D – providing a ready reserve of stores.
Dietary sources of Vitamin D are egg yolk, oily fish such as salmon and sardines, cod liver oil, Vitamin D fortified bread and cereals, or milk. Be mindful though a standard glass of milk will provide about 100 IU of Vitamin D only, so in Australia sensible sunlight exposure remains the safest, easiest and most effective method to maintain optimal Vitamin D levels.
