The amount of UV exposure needed to maintain vitamin D levels depends on the time of year, location, skin type, day-to-day activity and individual circumstances. There are seasonal variations in vitamin D levels. For example, in Victoria levels are, on average, lower at the end of winter when compared to summer.
May to August in Victoria
At this time of year, it is very difficult for our bodies to make enough vitamin D because:
- there is less sunlight
- UV levels are low
- we cover our skin up to keep warm.
From May to August, aim for sun exposure to be:
- longer (about 20 minutes in the middle of the day)
- expose as much skin as practical – you need sunlight on as much skin as possible.
Sun protection is not needed when the UV levels are below 3 unless:
- near highly reflective surfaces such as snow or water
- outside for extended periods (most of the day).
In Victoria, the average UV is below 3 from May until August, making it a great time to roll up your sleeves and get some winter sun. Most people need between two and three hours of midday winter sun exposure spread over a week to help with their vitamin D levels. People with naturally very dark skin may need more sun exposure.
Watch this short video to find out how much sun you need to maintain healthy vitamin D levels in winter.
September to April in Victoria
Whenever UV levels reach 3 and above , the UV can cause damage, increasing your risk of skin cancer so sun protection is required. In Victoria, average UV levels are 3 and above from September through to April. Most Victorians require only a few minutes of mid-morning or mid-afternoon sun exposure. Be extra cautious in the middle of the day when UV levels are most intense. People with naturally very dark skin may need more sun exposure.
Sunscreen use during the sun protection times should not put people at risk of vitamin D deficiency . When sunscreen is tested in laboratory conditions it is shown to block vitamin D production, however regular use in real life shows little effect on vitamin D levels. This is probably because people who use more sunscreen spend more time in the sun, so naturally they will have higher vitamin D levels.
Use the SunSmart UV Alert or SunSmart app to see if sun protection is needed on any given day for your location.
The map here shows how the amount of sun needed to help with vitamin D levels varies for different parts of Australia.