Be safe in the sun, can nutrition help? Part I

In my last post I wrote about the importance of vitamin D and sensible sunlight exposure.  This led me to start investigating natural ways to prevent skin damage from the sun (photo-damage) and sunburn.  The concept of photo-protection by dietary means is gaining increasing amounts of attention from the scientific community. 

Sun exposure leads to photo-ageing, with chronic sun exposure being a major contributor to ageing skin which is characterised by wrinkling, loss of elasticity, increased skin fragility and slower wound healing.  This photo-ageing probably occurs for a number of different reasons:

1. UV light can damage skin cell DNA via production of destructive ‘free-radical’ molecules .
2. UVB rays seem to induce the synthesis of enzymes which cause collagen, (and other skin tissue components), in the skin to degrade, this contributes to wrinkling, loss of elasticity and fragility.
3. UV light can also induce inflammation in the skin which contributes to photo-ageing.

Luckily there are some natural ways that can help us to protect our skin from sun damage. 

Antioxidants may help to ‘quench’ the destructive free radical molecules and therefore protect against photo-damage.  Specifically; beta-carotene, lycopene, lutein, vitamin C and vitamin E seem to be most helpful.  These plant constituents are involved in the light-protecting system in plants and may contribute to the prevention of UV damage in humans.  As nutrients they are ingested in the diet and are then distributed into the skin tissues where they provide the body with photo-protection.  

A diet rich in colourful fruits, vegetables, nuts and seeds will provide plentiful amounts of these antioxidants.  Beta carotene, lutein and lycopene are all carotenoids.  Carotenoids are a family of over 700 naturally occurring yellow, red and orange pigments found in vegetables and fruits.  Good sources include carrots, sweet potatoes, tomatoes, squash, peppers, cantaloupe melons, nectarines, papaya, mango and dark green vegetables such as spinach, watercress and asparagus.  Introducing a good mix of these fruits and vegetables in the diet will help keep carotenoid levels in the body high.

Absorption of these carotenoids from foods into the body is greatly affected by fat.  Without a fat source almost no carotenoids will be absorbed.  Fat acts as a carrier for the nutrients.  Now, I am not suggesting that you drown your vegetables or salads in ‘any old lard’, however I am a firm believer in using small amounts of olive oil in dressings and cooking.  Or including some nuts, seeds or olives in salads will also be helpful in order to gain maximum absorption of these important nutrients.

Two human studies have looked at tomato consumption and blood serum lycopene levels with regards the risk of sunburn(1,2).  The study groups were given lycopene or tomato-derived products rich in lycopene (mixed with olive oil) for 10-12 weeks.  Their blood serum lycopene levels increased with supplementation and they experienced a decrease in their sensitivity toward sunburn.  Sunburn damage was up to 48% lower in the groups receiving lycopene/tomato paste compared to the control groups.

Supplements containing antioxidants such as the carotenoids, vitamin C and vitamin E may also be useful in slowing down the time of development and grade of UVB induced sun damage(3).  If you feel that you are not getting a good supply of a variety of different fruit and vegetables daily in your diet, you may wish to consider taking a supplement to boost your levels of sun-protective antioxidants, especially in the sunny months or prior to a sunny holiday. 

Check back soon for Part II where I will be looking at how nutrition can help protect the skin from the inflammatory damage that the sun can cause.

(1) Stahl W et al.  2001.  Dietary tomato paste protects against ultraviolet light–induced erythema in humans.  Journal of Nutrition.  131(5):1449-1451.
(2) Aust O et al.  2005. Supplementation with tomato-based products increases lycopene, phytofluene, and phytoene levels in human serum and protects against UV-light-induced erythema.  Int J Vitam Nutr Res.  75(1):54-60. 
(3) Greul AK et al.  2002.  Photoprotection of UV-irradiated human skin: an antioxidative combination of vitamins E and C, carotenoids, selenium and proanthocyanidins.  Skin Pharmacol Appl Skin Physiol.  15(5):307-315

Written by Ani Kowal