There are only two ultraviolet light rays from the sun - UVA and UVB - that penetrate the ozone layer and reach the earth . Due to a significant increase in the published information around the capabilities of our skin to create Vitamin D from UVB rays, exposure to ultraviolet B has become quite a controversial subject.
Vitamin D is certainly having its moment in time as more and more research reveals just how effective it is in combating a variety of health problems. Indeed, if you learn to embrace the sun, or learn to use the power of sunlight to obtain the health benefits of Vitamin D, you can:
However, if UVB is now considered to be beneficial to our health, UVA exposure remains something to manage as it penetrates our skin more deeply and causes free radical damage. UVA reaches earth consistently throughout the year, from sunrise to sunset. Ultraviolet B, however, is very low in the morning and the evening. Best access to UVB rays from a Vitamin D production point of view, are therefore when they are most direct, ie. Midday.
As you can't avoid UVA to be able to get to the ultraviolet B, it is important to protect yourself from UVA rays. Worst time to be out in the sun without protection is therefore early morning or evening as you get next to no UVB and only UVA. So, you can't produce Vitamin D and you increase the risk of getting skin cancer. The worst of both.
Pregnant women are now being advised to increase their previously advised uptake of Vitamin D by up to 10 times - according to a CNN report. This will also provide for their newborns, who are believed to require a lot of vitamin D.
Besides eating certain foods that contain Vitamin D, or taking supplement tablets, an easy way to obtain a significant amount of additional Vitamin D daily, is to expose your body to the UVB rays as close to midday as possible, for about 10 - 20 minutes only, without sun protection. However, it's probably a good idea to wear sunscreen on your face, to protect it from the photo-aging effects of UVA. Make sure the sunscreen you choose contains excellent UVA coverage.
So when you have obtained enough ultraviolet B for your daily Vitamin D dose, it is important not to extend the exposure so much that you get sun burnt. This is when it is now time to use the conventional methods to protect yourself from any skin damage and skin cancers. Where not protected through your clothing, use a good sunscreen on all exposed skin. A 'good sunscreen' will depend on your skin type but either an SPF 15 or SPF 30 should be sufficient, together with excellent UVA coverage. Ie. a Broad Spectrum sunscreen. As shown in the graph below, it is important to note that an SPF 60 does not provide for double the coverage of an SPF 30.
In fact, anything over 30 provides for such a small increased amount of coverage that it does not warrant spending more money on a higher SPF. A higher SPF often induces a false sense of security where sun protection is concerned and many people then spend far longer out in the sun than they normally would and do not reapply as often as they should.
Most important though, is to make sure you have protection from both UVA and UVB rays.