As we bask in one of the warmest days of the year, please remember these facts and stay safe. You can not step back the damage. The best method of sun protection has to be sun avoidance however this is not at all practical. The next best thing is to take action to avoid the adverse effects of the sun’s harmful UV rays in the form of sunburn.

Approximately 50% of the daily UV is received during the four hours around noon, it is at this time that the sun is most damaging.

Skin cancer is a growing concern in the UK, where there are now more deaths from the disease every year than in Australia. Cancer Research UK reports a worrying gap between how much people know about skin cancer and how little they actually do to protect themselves in the sun against the country’s most common form of the disease.

Around 62,000 cases of melanoma are diagnosed every year, and among young people it is the third most common form of cancer.

“Unless young people change their habits and learn to protect themselves properly in the sun, we could be heading for a skin cancer time bomb.” – Cancer Research UK Website.

Teachers and parents have an important role to play in explaining the dangers of the sun’s UV rays and discussing sun protection. Skin cancer and sun protection are relevant to many different subjects and learning stages.

Try to follow and educate children on the five sun smart messages:-

Stay in the shade between 11.00am – 3.00pm.
Make sure you never burn.
A lways cover up with a t-shirt, wide brimmed hat and sunglasses.
Remember to take extra care with children.
Then use factor 15 plus sunscreen.

What the sun could do to you today
This week may see not only the hottest days of the summer but also the hottest days on record. What risk does it pose to your health? Here, we explain just what harm - and good - the sun can do to the body:

The skin
Sunburn is the body's chemical response to over-exposure to ultraviolet light in sunlight. It is not like a normal heat burn. When you get sunburnt, the outermost layers of your skin release chemicals that cause your blood vessels to swell and leak fluids. This causes inflammation, pain and redness.

Four to seven days after exposure, skin may start to peel. This is the body's way of getting rid of damaged cells which are at risk of becoming cancerous. Severe sunburn can result in chills and fever, second-degree burns, dehydration, electrolyte imbalances, infection, shock and death.
There are four types of skin cancer: the most serious, melanoma, develops in cells in the outer layer of the skin. The first sign may be a change in the look or feel of a mole. Sun exposure can trigger cold sores.

Research shows 10.4per cent of cold sore sufferers had a flare-up related to ultraviolet light. The rate rose to 19.7per cent among patients diagnosed in July and August, and to 28per cent among patients under 30 diagnosed in July and August. These results suggest the important role of solar ultraviolet (UV) radiation in the development of recurrent herpes. It could, they add, be due to the effect of UV suppressing the immune system.

Sleep
Hot nights can make a good night's sleep virtually impossible. That's because our bodies normally cool down by several degrees centigrade as they prepare for sleep. If this cooling is interrupted, sleep becomes difficult.

About half an hour before we go to sleep, our bodies start to lose heat. That's why, in children especially, their cheeks become flushed and pink when they get tired. Bedclothes trap heat and drive up the body's temperature during the night, breaking up sleep and leaving us tired and irritable the next day.

The only way to cool down is to expose as much skin as possible to the air. The skin acts as the body's radiator by letting heat escape. Use cotton sheets and put a fan in your room. Better still, take a warm bath before you go to bed, not a cold one. This helps to cool the blood and keep your core temperature down.

Feet and hands
In the heat, the blood vessels near the surface of the skin dilate (widen) to help get rid of the heat, causing the skin to become red. The hands and feet swell with the pressure of the dilated blood vessels, making rings and shoes uncomfortable.

Hair
Sunlight bleaches hair. This is exacerbated by chlorine, dye, chemicals and relaxants because they make the hair more porous. Hair also becomes more brittle in the sun because the shaft loses moisture, so it is more likely to tangle.

However, hair cells are one of the fastest types of cell in the body to renew themselves. This increases in summer as warmth stimulates hair growth. Damage to the hair is, therefore, cosmetic, rather than permanent. However, people with thinning hair are at greater risk of a form of skin cancer known as squamous carcinoma, which though not malignant, requires urgent treatment.

Protect your hair and scalp by wearing a hat. A sunscreen spray or leave-in conditioner with a high SPF factor should also block UV rays and prevent the scalp from burning.

Heart
Limited exposure to hot weather can be good for healthy people because it increases the heart's efficiency. As the body tries to cool down, blood flow to the skin increases. This results in an increased output of blood - up to 29pc more - from the heart. However, if we are continually exposed to rising temperatures, all the blood vessels in the body widen or dilate. This causes a fall in blood pressure which makes the heart work harder. This can make us feel faint; we may even pass out.

The heart is an essential part of the body's cooling system because it delivers blood and water to cells while your body is trying to cool down by sweating. When you sweat, you lose fluid, decreasing your total volume of blood. A drop in blood volume can lead to a reduction in blood pressure, again making the heart work harder. Continued high temperature can increase the risk of heart attacks, particularly in the elderly people.

A study in the journal Heart found that extreme temperatures may increase risks for the over-70s. This is because their heart is already weak due to ageing. An elderly person or one suffering from a heart condition should avoid extreme heat and humidity because it places an extra burden on the heart and circulation.

Without enough water, blood becomes very concentrated. This means it is packed with platelets, which can trigger clots. "This doesn't matter for young, fit people, but for the elderly with arteries in poor condition it means they are much more likely to have a heart attack or strokes.

Digestion
Appetite is affected by heat. In cold weather, most calories we consume are used to keep us warm. When it's warm, the body does not need to generate its own heat. Experts say it is still important to eat at regular intervals because food triggers the body's thirst mechanism. By the time you feel thirsty, the body is in the early stages of dehydration.
Foods that contain normal levels of salt make us drink more and are crucial for maintaining fluid levels. The first symptoms of the body overheating include nausea and vomiting.

Kidneys
When your body is dehydrated, the kidneys try to conserve as much water as possible, as well as vital salts, such as sodium and potassium. Cells throughout the body rely on an adequate supply of water and salts to function properly. If the kidneys are not re-supplied with sufficient fluids - ideally, six to eight glasses of water a day - they could be damaged beyond repair. This can result in kidney failure, which can require dialysis and a kidney transplant. Strong-smelling urine that is yellow is a sign of dehydration.

Experts warn against taking salt tablets to top up what's been lost through sweat. Instead, just eat normal foods that contain salt as flavouring, and if you are on a low-salt diet, abandon it for a few days.

Eyes
Intense UV light can inflame the cornea - the eye's surface - causing pain and temporary loss of vision. The condition, known as photokeratitis or snow blindness, can be caused by dazzling sun rays, reflected from surfaces such as bright sand.

The symptoms appear six to 12 hours after sun exposure and the eyes can become red, swollen, watery and itchy. The problem clears up within a couple of days, but repeated exposure may lead to permanent blurred vision. Excessive exposure to UVA can lead to cataracts and macular degeneration in older people. It is important to wear UV-protective sunglasses in bright sunlight. Look for the CE or BS EN 1836: 1997 because these ensure a safe level of UV protection.
Sunglasses are also marked with a filter category number from zero to four. Category four is suitable for skiing, while category two or three should be fine for most occasions and summer holidays abroad.

Hormones
One part of the brain affected by dehydration, which the body may experience in the heat, is the pituitary gland. This is a gland at the base of the brain which releases hormones vital for growth and reproduction. Without enough water in the body, it starts to produce more of an antidiuretic hormone. This tells the kidneys to stop making so much urine and to retain water to reduce the stickiness of the blood. The sun has a more positive effect on another hormone, melanocortin. This operates in the parts of the brain where messages about food, sex and sleep are exchanged, and it seems to help you tan and feel sexy.

Armpits
In hot weather, the body uses perspiration to cool down. Sweat evaporates on the skin, lowering the temperature of the blood near the body surface. The blood circulates through the body, bringing down our core temperature. (The main 'cooling stations' are the armpits.) To help the body sweat, make sure your fluid levels are high. If you don't drink enough, the cooling system breaks down.

Brain
The fluids we drink not only run the body's natural cooling system, they keep the brain in good working order. If you don't drink enough, the body temperature soars. The brain is 70 per cent water and lack of hydration affects the way brain cells transmit instructions, making everyday tasks difficult and causing disorientation, dizziness and headaches.

Heatstroke can make people seem drunk. Once the body temperature goes above 42°C - which is a real risk in a heatwave such as this - as a result of ceasing to sweat because of dehydration, brain tissue starts to cook. The worst affected part is the cerebellum, which governs movement and co-ordination. Even if someone survives this, they can be left with brain damage affecting their movement.