How to get the Sunshine Vitamin D in Winter?
Most of your vitamin D tends to come from sunshine- your skin makes vitamin D through sunlight exposure. Your ability to produce vitamin D depends on how strong the sunlight is and is only made by skin which is exposed to the UV rays of the sun. However in Ireland and the UK, our exposure to sunlight is limited to the months of April to September. During winter months, your body gets its vitamin D from body stores and also from a limited number of food sources. However body stores have been shown to be insufficient to last for the winter months and the best way to ensure adequate vitamin D levels is by taking a vitamin D supplement (see recommendations below).
Vitamin D is an important vitamin for a number of reasons in combination with a calcium rich diet. It works with calcium and phosphorus to ensure healthy muscles, bones and teeth. Without vitamin D, calcium cannot be absorbed into bones and body cells.
Food sources of vitamin D
While certain food contain vitamin D, for most, the amount provided by diet tends to be insufficient as only a limited number of foods contain vitamin D.
Food sources of vitamin D include; oily fish (salmon, mackerel, tuna), liver, eggs and fortified foods (e,g cereals, fortified dairy).
Vitamin D deficiency
Deficiency can lead to reduced muscle strength, increased risk of falls particularly in older adults, delayed or stunted bone growth and rickets (bone pain, delayed growth and deformities) in children and osteomalacia. It is also though that vitamin D plays a role in the prevention of cardiovascular disease.
New research published in Ireland has shown Vitamin D deficiency is very common particularly in older adults. One in 8 adults over the age of 50 is deficient in vitamin D in summer (when the body normally produces vitamin D), while this increases to 1 in 4 adults in the winter months.
Vitamin D deficiency is also more likely as people age. Other factors which have been shown to increase the likelihood of vitamin D deficiency included: smoking, living alone, physical inactivity and socio-economic background.
Vitamin D intake recommendations
In both Ireland and the UK, vitamin D supplements are recommended for infants in the first year of life. In Ireland, it is recommended that a Vitamin D only supplement of 5ug be given to all babies (regardless of whether they are breast fed, formula fed or on solid food). Vitamin D is particularly important during the first year of life for growing babies to help lay down strong bones. In the UK, a 10ug supplement is recommended for infants.
For adults, in Ireland, intake recommendations are currently in draft, but it is proposed that everyone in Ireland take a 5ug vitamin D supplement daily. It is likely that older adults require 10ug of vitamin D per day. In the UK, the British Dietetic Association recommend all adults and children take a vitamin D supplement of 10ug/day especially during autumn and winter.
