Why is Vitamin D important? Vitamin D is essential for the absorption of calcium from the gut and for optimizing bone health. Clinical Vitamin D deficiency can lead to osteomalacia (soft bones) in adults and rickets in children. In older adults, low levels of Vitamin D have been shown to increase risk for osteoporosis, falls and fractures.
Why is Vitamin D important?
Vitamin D is essential for the absorption of calcium from the gut and for optimizing bone health. Clinical Vitamin D deficiency can lead to osteomalacia (soft bones) in adults and rickets in children. In older adults, low levels of Vitamin D have been shown to increase risk for osteoporosis, falls and fractures. Vitamin D is also thought to have a role in maintaining a healthy immune system, healthy skin and muscle strength.
How do we get our Vitamin D?
The main source of Vitamin D is sunlight on the skin rather than diet. There are very few foods that contain significant amounts of Vitamin D and it is not possible to meet daily Vitamin D requirements through diet alone. Natural sources of Vitamin D are found in oily fish (salmon, herring and mackerel) although farmed salmon contains only ¼ of the amount of vitamin D as wild salmon. Margarine and some fortified milk varieties contain small amounts of Vitamin D as do some UV exposed mushrooms.
In most cases, people can maintain adequate Vitamin D levels through incidental (day-to-day) outdoor exposure. It is safe to go outside without sun protection in the early morning and late afternoon when the UV Index is below 3. You can find the daily UV forecast at www.myUV.com.au.
Who is at risk of low Vitamin D levels?
A recent national study reported that 6% of Australian adults had a moderate Vitamin D deficiency. Overall, rates of deficiency were very similar for both men and women. In winter, rates of Vitamin D deficiency were particularly high for those living in the south eastern states of Australia.
People identified as most at risk of Vitamin D deficiency include those who:
- Have darker skin
- Spend most of their time indoors
- Are obese
- The elderly and people who are housebound or institutionalized
- Cover up for cultural or religious reasons
- Live in the southern areas of Australia, (during winter)
- Train or compete predominantly indoors
- Have diets that are very low in fat
- Babies and infants of Vitamin D deficient mothers, especially if the babies are exclusively or partially breastfed (reference)
- Patients with osteoporosis
Do I need to take a Vitamin D supplement?
If you are considered to be at risk for Vitamin D deficiency it is a good idea to get your GP for a blood test to check your Vitamin D levels. If your levels are low, your GP will prescribe appropriate supplementation to correct the deficiency. Otherwise, the best approach to maintain adequate Vitamin D status is one that combines moderate and safe sun exposure and available Vitamin D-containing foods.
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