Smart sunlight exposure is essential for optimal health, as the primary source of vitamin D for most people is solar ultraviolet-B (UVB). But we have been told that unprotected skin can be severely damaged by the sun's rays, resulting in visual ageing such as wrinkles, age-spots, sagging skin and possibly skin cancer.
UV rays have three wavelengths; Ultraviolet A (UVA), Ultraviolet B (UVB), and Ultraviolet C (UVC). Although scientists claim that the longer wavelength UVA is the least harmful and the shorter wavelength UVB are most damaging to DNA, UVB rays are important for bone health and cancer prevention, as they are responsible for triggering the production of vitamin D in your skin, whereas UVA radiation could actually destroy vitamin D, increase oxidative stress, and increase photo ageing of your skin when exposed to excess sunlight. When you’re exposed to sunlight through windows in your car, home or your office, you get the UVA but not the UVB, because only UVA rays are able to penetrate glass and clothes and set off a chain reaction underneath the skin on a deeper level, causing long-term damage to the collagen fibres.
Vitamin D is an essential ingredient for optimising health and preventing disease; it helps to lower the risk of heart disease, high blood pressure, diabetes, multiple sclerosis and depression. The Vitamin D Council recommends 2000 - 10,000 IU of vitamin D daily, but our need for vitamin D varies with age, body weight, skin pigmentation and overall health. As a general rule, older people need more vitamin D than younger people, obese people need more than skinny people, and dark skinned people need more than fair skinned people.
How much sunlight exposure is safe?
Moderate sun exposure offers more health benefits than risks. The best way to take advantage of the sun as a source of vitamin D is to expose as much of the body as possible (without sunscreen) when the sun is highest in the sky which is around noon, the time when one's shadow is shorter than one's height, as UVB levels are at its highest at this time. A 10-minute sun exposure to face and hands result in the endogenous production of roughly 400 IU of cholecalciferol (D3). It is then transported to the liver and converted by an enzyme in the kidneys to 1,25-hydroxycholecalciferol (the most active and potent form of vitamin D). High levels of vitamin D from endogenous synthesis due to sunlight exposure is relatively safe and does not produce toxicity. You get better vitamin D absorption from sun exposure on the skin than the food you take. With whole body exposure to the sun, one can make 10,000 IU a day in 20-30 minutes, depending on your skin pigmentation and health conditions, but be careful not to overdo it; you don’t want your skin to turn red or burn.
Is your sunscreen doing more harm than good?
Sun protection is important if you plan to stay under the sun for a long time, but applying chemical-laden sunscreen on the skin is far worse than getting natural sunlight. Commercial sunscreens contain toxic chemical ingredients that can raise your risk of developing skin lesions and tumours, instead of protecting against melanoma. Many of these ingredients are endocrine-disrupting chemicals that can cause cell damage and hormone disruption, possibly leading to the development of breast cancer in women and disturbing pubertal development in girls. These UV screen chemicals, including Oxybenzone, PABA, Retinyl Palmitate, Avobenzone, Homosalate, Benzophenone, Salicylates, and Cinnamate are usually used in a variety of cosmetic products in concentrations of up to 10-15 percent. Even some natural sunscreen ingredients such as zinc oxide and titanium dioxide may have unforeseen consequences for your skin health, as these substances may contain nano-sized particles that have been shown to cause DNA damage in skin cells when exposed to UV light and water.
The Sun Protection Factor (SPF) value of a sunscreen doesn't guarantee better or longer protection from UV ray exposure. Most SPF in your lotions may protect against UVB only, which prevents vitamin D from being produced. While SPF in sunscreens may be useful in reducing the risk of sunburn, they do not block the long wave of UVA.
If you would like to stay in the open sun for long hours without getting sunburn, you can protect and cover your skin with protective clothing and stay in the shade to limit your UV ray exposure. Alternatively, choose safe and non-toxic natural oils such as Wheatgerm oils, Coconut oils, Avocado oils, Olive oils, or Raspberry seed oils to moisturise your skin.
True beauty flourishes from the inside.
Your best secret weapon to having younger-looking skin is to top up on antioxidants and healthy fats in your diet, as they help to protect the skin cells from DNA damage caused by UV radiation. Your body has several enzymes that prevent the damage induced by free radicals; these are superoxide dismutase (SOD), catalase and glutathione peroxidase. Dietary antioxidants from foods that are rich in vitamin C and E, selenium, beta-carotene, flavonoids, coenzyme Q10, and sulfur-containing amino acids, work to increase the body's own production of its natural antioxidant enzymes, helping the body to disarm the free radicals that are triggered by UV rays, and reducing the risk of getting skin cancer, ageing, and skin irritation.
Glutathione is known as a powerful detoxifier. It sweeps up dangerous free radicals, helps to boost immune system and reduces the risk of cancer and as well as the size of tumours. As glutathione itself is so big and hard to assimilate, taking a stand-alone supplement is not recommended. You need a good range of B complex and some amino acids, including L-glycine, L-glutamine and L-cysteine to feed and help your body to make the glutathione.
Omega 3 fatty acids have a wide range of anti-inflammatory and immunomodulatory functions. Dietary supplements with omega 3 fatty acids reduce the risk of getting sunburn and cancer progression that are caused by UV radiation. A tablespoon of fresh Flaxseed oil daily may supply these essential fatty acids that are useful to initiate cell renewal after a UV radiation burn.
Remember, sunlight is not the only source of UV radiation. Other sources include sunlamps, tanning booths, Mercury vapour lighting (often found in stadiums), some halogen, fluorescent, and incandescent lights and some types of lasers. UV radiation is also not the only risk factor of skin cancer. Some people who get large amounts of sun exposure may not get melanoma, and people who do get melanoma might not have been exposed to much sunlight.
Have a happy and worry-free sunny day!
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