July 20, 2015
328 The Sunshine Vitamin [20 July 2015]
This is a compilation from several previous posts on Vitamin D. We’re getting some hot sunny days now so optimizing D synthesis while protecting from sunburn is important.
The best way to get vitamin D is from the sun. But for most of the year in Saskatchewan, unless you use a safe sunlamp or take a holiday in the tropics, supplementation is the only way to keep your D levels up.
The UVB rays necessary for vitamin D synthesis can only penetrate the atmosphere when the sun is at 50° or more above the horizon. For our latitude this occurs only from mid-April to mid-August. At the beginning and end of this period there is about a half hour “window” centered on 1:15 pm (which is the “sun-noon” for Rosetown’s longitude). For most of June the “window” extends from 11:00 am to 3:30 pm. On sunny days outside these time “windows”, and on cloudy days, you can still get a sunburn (and increase your risk of skin cancer) from UVA, but you can’t make any vitamin D.
How can we optimize our vitamin D while protecting ourselves from sunburn and possible skin cancer? Expose as much skin area as possible, without SPF sunscreen, for 10-15 minutes during the peak UVB window. Stop before the skin turns pink. As you tan throughout the summer the length of exposure can gradually increase. Don’t wash exposed skin with soap for 48 hours after exposure to allow the vitamin D to be absorbed (washing with plain water is fine).
Cover up with a hat and clothing or use sunblock the rest of the time. The two safest and effective ingredients for blocking the more harmful UVA rays are zinc oxide and titanium oxide which block both UVA & UVB radiation. Remember glass and clouds block UVB but not UVA so you can get a sunburn in your car or on a cloudy day but you can’t make vitamin D.
Regular low intensity sun exposure does not increase the risk of melanoma and actually lowers the risk of many other cancers. Studies have linked higher exposure to UVB with lower rates of 20 different cancers. Optimum vitamin D levels also appear to protect against sunburn – many people (myself included) find that since taking D supplements they don’t sunburn as easily.
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.