How to avoid sun damage and heat stress

We all love hot summer days at the beach or on a family picnic, but we all know too well how quickly skin damage, eye damage and heat stress can happen when we are having a load of fun in the sun!

Some exposure to sun is healthy whist too much causes disease, so it is wise to take note of how to avoid the negative side effects of too much sun.

6 quick points to note and remember about the sun and our reaction to it:

1. A little sunshine has health benefits but too much causes disease.
2. Sunshine dehydrates the body, damages skin and causes skin cancer, photo-aging, cataracts and eye tumours (benign and malignant).
3. Sunshine replenishes vitamin D stores, reduces myopia (shortsightedness) and reduces depression.
4. If blood vitamin D levels are truly low, dietary supplementation (fish) plus vitamin D supplements are probably safer than increasing sun exposure.
5. Don’t be fooled by cloud cover! The sun’s rays can pass through thin and hazy clouds.
6. Remember to slip, slop, slap, seek shade and slide on a pair of “sunnies”.


The ancient Greeks believed that Apollo the Sun God harnessed his chariot to take the sun across the sky. He was seen as a healer and the God of Medicine but also the God of Plague who spread diseases and pestilence.

Just as Apollo encompassed both cure and disease, so does the sun. Sunlight is made up different ultraviolet (UV) frequencies. UVB is the frequency responsible for sunburn, skin cancer, hyperpigmentation, and photo-aging: in fact UV radiation is responsible for 80% of our skin’s fine lines, wrinkles and sagging.

However sunlight has other effects too.


Sun and the skin

Certain skin types are more vulnerable to the effects of the sun (white skin with blue eyes more than dark brown to black skin). But everyone regardless of skin type is at risk. Photoprotection is crucial for ALL skin types. This includes sun avoidance at peak hours, sunprotective clothing and sunscreens


1.     Sun Avoidance

A score >3 on the World Health Organisation UV Index is when sun protection measures are required. Australia is consistently above 3 all year round except in the winter months in certain regions. In January the UV index is extreme.

Don’t be fooled by cloud cover! The sun’s rays can pass through thin and hazy clouds.


2. Sun Protective Clothing

Hats, long sleeves shirts, collars are all recommended particularly on hot summer days when prolonged sun exposure may occur. Some clothes have been given a ultraviolet protection factor (UPF rating). A UPF 50 allows only one 50th of UV radiation to filter through to your skin.


3. Sunscreen: Which to use?

Broad spectrum sunscreens with high sun protection factor (SPF 30+), particularly those with ingredients that protect against UVA1 (e.g. Zinc oxide, titanium dioxide and avobenzone) are preferred for those going out in the Australian sun. Cosmetics that use broad spectrum protection with an SPF 15- 30 are preferred to those only containing UVB filters.


Sunscreen in children:

Parents should avoid direct exposure to baby’s skin in the first year if possible. But this can be difficult, so The Australian College of Dermatologists recommend sunscreens be used at any age when exposed to the sun if clothing/shade is not available. Since infants have an immature skin barrier, oil-based emulsions such as titanium dioxide or zinc oxide are preferred as they have broad spectrum protection and minimal irritation.


How much to put on and when?

Sunscreen must be applied liberally and frequently.  If you don’t put enough on, it wont work. The teaspoon rule is a good guide in children: 1 teaspoon to face and neck, 2 to back and front torso, 1 teaspoon to each arm, 2 to each leg.

It should be applied 15- 30 minutes prior to sun exposure to allow a protective film to form. Reapply every 2 hours, even for those that are water resistant.


SUNBURN: top tips

●     Moisturiser cream may help soothe the skin.

●     If pain is associated, try non steroidal ant-inflammatory analgaesics like ibuprofen (e.g. Nurofen)

●     Do not de-roof blisters, as this may lead to infection. Cover the blisters with gauze.

●     Ensure you drink plenty! Sunburned skin loses moisture faster.

●     Do not go out into the direct sunlight until your sunburn has resolved


SUN and the EYES

Eye Sunburn: Photokeratitis and photoconjunctivitis

Just like sunburn to the skin, eyes that are exposed to excessive UV radiation become red, sore and sensitive. Prolonged exposure can also cause eye tumours (benign and malignant) and cataracts. Hence, wear sunglasses (preferably with large / wraparound lenses) that block 99-100% UVA and B radiation. Don’t be fooled by a dark tint alone. A dark tint does not necessarily mean that the sunglasses fit this criteria. Your kids need them too.


SUN : The benefits

Vitamin D

Sunlight (especially ultraviolet B, UVB) is essential for the synthesis of vitamin D which helps us absorb calcium and phosphate from our food. When levels of vitamin D are low, there is a risk of bone disease. In children this is called Rickets (suffered by Tiny Tim from A Christmas Carol, along with TB) and is rarely seen in Australia. In grownups, especially the elderly, inadequate vitamin D causes Osteomalacia and can cause fractures when elderly people fall.

It is also suggested (but not definitively proven) that vitamin D has a role in preventing heart disease, cancer and asthma.

The amount of sun exposure required to get the benefits of Vitamin D depends on skin type, geography and UV index. Given the risks of sun exposure,  dietary supplementation (fish) plus vitamin D supplements would seem safer if blood vitamin D levels are truly low.


Depression: Seasonal Affective Disorder

We all feel uplifted with the big bright blue skies of an Aussie summer. Consequently it is not surprising to note that some patients describe increased depressive symptoms in late autumn and winter which improve once summer arrives. Such cyclical symptoms are part of Seasonal Affective Disorder. In addition those with bipolar disease may describe increased symptoms of mania or hypomania in the summer but less so in the winter. It is postulated that sunlight may have a direct effect on serotonin levels and thereby account for these changes in mood.


Myopia (Shortsightedness)

Studies suggest that if children spend less time in the great outdoors, then short sightedness /myopia can ensue. The prevalence of myopia has doubled in the USA and Europe over the last 50 years and links with the amount of sun exposure/light have been suggested.


In conclusion

Just like anything else, enjoy the sun sensibly and take in moderation! In particular, wear good quality sunscreen and sunglasses and remember to ‘slip, slop, slap, seek and slide’.



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Sunscreen Use: Controversies, challenges and regulatory aspects. Br J Dermatolo 2011: 165: 255