The Benefits Of Sunlight
As we all should know, sunlight exposure is incredibly important to our health.
One of the world’s best authorities on UV exposure is Dr Michael F. Holick, author of the UV advantage. Here is my take on his (and a few others) work to get started.
- Firstly we need UVB rays to produce Vitamin D in our bodies. UVA, in terms of Vit D production, is like trying to take your girlfriend out to the local fish and chip shop for her birthday – it just does not cut it. This means if we want to get Vit D from the sun, you can disregard the whole ‘stay in the shade from 10am to 4pm’. The reason is that UVB rays are virtually non-present outside of these times.
- The closer you are to the North or South poles, the harder it will be to get & make Vit D in the wintertime. However because Vit D is a fat soluble vitamin, if you get enough sun exposure during the spring, summer & autumn, the excess Vit D can be stored in the body’s fat stores.
- Sunscreens as little as SPF8 will reduce Vit D production by as much as 95%. SPF15 will reduce it as much as 99%.
- The older you are, the harder it is for you to manufacture Vit D. Your ability to make Vit D actually decrease fourfold from ages 20 to 70 years. Studies also show that most individuals over 65 years are Vit D deficient. As Vit D is directly related to bone health, I would start to become worried about hip operations and falls, rather than getting wrinkles on the old mug.
- Just like age, the darker your natural skin colour is, the more sun exposure you need for Vit D production to occur. To demonstrate this, 40-60% all African Americans in the U.S. are Vit D deficient and may need up to 10 times the amount of sun exposure to make a similar amount of Vit D as a fair skinned person.
- Coming from the skin cancer capital of the world (Queensland), I was a bit worried about the risk of skin cancer & melanomas. However, there is no credible evidence that frequent moderate sun exposure causes melanoma. In fact melanomas usually occur on parts of the body that have little to no exposure and they occur more often in people who have little exposure than those who spend time in the sun. Genetics can also be blamed for skin cancers & melanomas rather than time spent ‘soaking up the rays’.
- Before I get misunderstood, the key here is avoiding getting sun burnt, which is thought to be the culprit behind melanomas. If you avoid sunburn and gradually accumulate a tan from regular sun exposure, this moderate sun exposure will far outweigh any dangers.
- You still need to take precautions so you do not get burnt after the initial sun exposure. Determine the amount of time based on your skin colour, season, time of day and latitude that will not burn you. If you want to stay in the sun after this point, then cover up or add a sunscreen.
- The best way to test if you have enough Vit D is your blood concentration of 25(OH)D. This will reflect vitamin D produced cutaneously (from the skin) and that obtained from food and supplements. Although serum 25(OH)D levels do not indicate the amount of vitamin D stored in other body tissues, it is still considered the standard blood test for Vit D. If you are worried about this, ask your doctor to include it in your next check up.
So why is this Vitamin D stuff so important? There have a number of studies recently that show why you can consider Vit D as the ‘Mr. Popular’ of vitamins. Here are a few.
- Researchers at a Romanian university gave older adults bread supplemented with 5000 IU of vitamin D per daily serving. They all demonstrated significant increases in bone mineral density without any evident adverse effects.
- A recent study published in the International Journal of Cancer found that the active form of vitamin D (D3) acts on a gene that increases the activity of an important antioxidant enzyme (glucose-6-phosphate dehydrogenase). This enzyme they found virtually cleaned up free radicals in prostate cells.
- The U.S. National Health & Nutrition Examination Survey found that adolescents with high intakes of vitamin D may have lower overall body fat and lower amounts of abdominal fat. On the other hand, low levels of Vit D were linked with increased blood pressure, blood sugar and metabolic syndrome in teenagers.
- This one is from our friends at Harvard and was based on two HUGE studies – the Nurses Health Study and the Health Professionals Follow Up Study. They basically found that colon cancer patients with the highest levels of Vit D were 48% less likely to die from ANY CAUSE (let alone colon cancer) than those with the lowest levels.
To be honest, I flicked through around 25 of these studies and it all basically amounted to this.
Vitamin D due to UVB radiation or ingestion of Vit D3 (the active form of Vit D) will help your reduce your risk of almost every disease out there including colon, breast, prostate & ovarian cancer, heart disease, high blood pressure, Type I diabetes, MS and depression. I even came across studies demonstrating improved muscle force, power and jump height in adolescent female athletes. It has also been shown to improve cognitive output while also decreasing upper respiratory tract infections. This is especially important to athletes, corporate businessmen and anyone who needs to produce high levels of performance day in and day out.
Now if you are still concerned about the skin cancer risks or if you live further from the equator, there is also the really viable option of Vitamin D supplementation. In fact if you are not getting 25% of your body in UVB light for at least 10 minutes 3 times a week if you are fair skinned (longer for the darker skinned), I would definitely recommend Vit D supplementation. Remember that you only really get UVB light between 10am & 4pm and as most of us have day jobs, this can leave us all pretty thin here. As previously mentioned, the form of Vit D you want to make sure you take is Vit D3. The Institute of Medicine and most of the experts recommend between 1000 - 2000 IU per day and preferably 2000 IU. Considering Vit D3 is one of the cheapest supplements you can buy (around $15 for 90 1000 IU caps), it makes sense to add this to your regime. This is definitely going to be on my supplement protocol come winter and I highly recommend you include it in yours.