Health experts are warning of the signs of a serious health problem in the very hot weather.

As forecasters warn to stay indoors and that temperatures could reach 40 degrees, medical experts say it’s important to look after your wellbeing – making sure you’re drinking enough water, and not spending too much time in the sun.

A rare amber warning has been issued across a large part of the UK, stating there could be a danger to life or potential serious illness due to the high temperatures.

Dr Angela Rai, GP at The London General Practice says: "“Signs of heat exhaustion include dizziness, headaches, excessive sweating and pale, clammy skin, cramps in your arms and legs, fast breathing or pulse, breathlessness and feeling very thirsty.

"“However, these symptoms can also indicate other health conditions."

“In hot weather, you may notice a decrease in your appetite,” says Dr Bryony Henderson, lead GP at digital healthcare provider, Livi.

“This is because our bodies are trying to regulate our body temperature by cutting down on heat-generating functions like the digestion of food. However, if you have been experiencing a persistent loss of appetite that doesn’t seem to be related to a simple explanation, such as the hot weather, consult with your GP.

If breathlessness persists – or you suspect it’s not due to the heat – Rai says it can also be a sign of heart or lung conditions. She recommends watching out for signs of wheezing, as this could potentially signal “an underlying lung condition”.

Feeling sweaty is part and parcel of extreme temperatures. However, if your normal sweating is coupled with pale and clammy skin, Rai says this can be associated with heart conditions, especially if there is also chest pain.

She says: “If there is chest pain and sweating, this could be angina or even signs of a heart attack, and urgent medical attention is required.”