Temperatures across the UK are set to reach over 30 degrees celsius today.
Heat stroke and heat exhaustion can occur when people get too hot, during a heat wave or in a hot climate.
They can also occur when people are doing too much strenuous exercise and experts argue possible heatstroke must be treated as quickly as possible.
Heat exhaustion happened when people become very hot and start to lose water or salt from the body, where as heat stroke means the body can no longer cool itself – causing the person’s body temperature to become dangerously high.
Heat stroke usually occurs when the core temperature of the body reaches over 40C.
Heatstroke is less common, but more serious.
It can put a strain on the brain, heart, lungs, liver and kidneys, and can be life-threatening, according to NHS Choices.
Experts warn heat exhaustion or heatstroke can develop quickly – or gradually over several hours or days.
The NHS said symptoms of heat exhaustion include:
dizziness and confusion
loss of appetite and feeling sick
excessive sweating and pale clammy skin
cramps in the arms, legs and stomach
fast breathing or pulse
temperature of 37C or above
Symptoms of heat stroke include dry hot skin, no sweating and a temperature of 40C or above.
People suffering with the condition should be moved to a cool place, and any unnecessary clothing should be removed.
People should lie down and raise their feet and drink plenty of water.
Experts also suggest cooling a patient’s skin with cool water or ice packs.
If their condition does not improve after 30 minutes
Dr Thomas Waite from PHE said: “Much of the advice on beating the heat is common sense and for most people there’s nothing to really worry about.
“For some people, such as older people, those with underlying health conditions and those with young children, the summer heat can bring real health risks.
“That’s why we’re urging everyone to keep an eye on those you know who may be at risk this summer. If you’re able, ask if your friends, family or neighbours need any support.
Unusual levels of UV are also being recorded in the UK at the moment – with the strength of the UV in some spots being as high as that in Cyprus and Gibraltar.
This has prompted warnings that people should take extra care in the sun at the moment and should keep an eye on PHE’s UV monitors.
The top ways for staying safe when the heat arrives are to look out for others, especially older people, young children and babies and those with underlying health conditions, close curtains on rooms that face the sun to keep indoor spaces cooler and remember it may be cooler outdoors than indoors, drink plenty of water as sugary, alcoholic and caffeinated drinks can make you more dehydrated.
Experts said people should never be left in a closed, parked vehicle, especially infants, young children or animals and advised people to keep out of the sun between 11am to 3pm.
Public Health England said people should walk in the shade, avoid physical exertion apply sunscreen and wear a hat if you have to go out in the heat.