The Victorian Health Monitor Report released today reveals that over 50% of Victorians have vitamin D deficiency in winter. Prevalence of vitamin D deficiency is two and a half times higher in winter (53%) as compared to summer (20%), highlighting the impact of seasonal variability in ultraviolet (UV) radiation on vitamin D levels.
SunSmart Manager, Jen Makin, said: "We know that the amount of sun needed to make enough vitamin D depends on a number of factors including UV levels, which peak in summer and are their lowest during winter in Victoria."
"The body only stores enough vitamin D to last between 30 and 60 days, so even though it's not difficult to get enough sun exposure during summer in Victoria, this new report shows Victorians are not getting sufficient winter exposure."
"It is not cause to panic. The majority of Victorians found to be deficient were in fact only mildly vitamin D deficient. This is easily treated with minor lifestyle changes. The key is to take a balanced approach to maintaining vitamin D levels all year round. From September to April, UV levels are on the rise so most Victorians require only a few minutes of mid-morning or mid-afternoon sun exposure to the face, arms and hands (or equivalent area of skin) for vitamin D. Prolonged sun exposure does not further increase vitamin D levels, but does increase skin cancer risk."
"Victorians need to be extra cautious during the middle of the day when UV levels are most intense and remember that sensible sun protection does not put you at risk of vitamin D deficiency, so be sure to use sunscreen if you will be outside for longer than a few minutes. Never try to boost vitamin D levels through excessive UV exposure or by using solariums."
The report also reveals a relationship between skin type and vitamin D deficiency. Those with naturally very dark skin were more than five times more likely to be vitamin D deficient than were those with fair skin. Furthermore, men with brown or olive skin (Mediterranean or Asian skin that burns less easily than fairer skin types) were also nearly twice as likely to be vitamin D deficient as those with pale skin.
Ms Makin said: "We know that naturally very dark skinned people are at increased risk of vitamin D deficiency due to the higher levels of protective melanin in their skin, which affects UV penetration. Consequently, these groups may require more UV exposure to make vitamin D."
The Department of Health's Victorian Health Monitor is a physical and biomedical measurement survey. Fieldwork for the Victorian Health Monitor study was undertaken between April 2009 and June 2010 using a stratified cluster sampling design.
The data collected from the Victorian Health Monitor will be used to target interventions for men and women at particular ages from different socio-economic backgrounds to support chronic disease prevention activities.