Dr Sarah Jarvis has advised who should be most careful amid the UK heatwave, and which people are most "at risk".
The Good Morning Britain doctor said that heatstroke and heat exhaustion were common amid high temperatures, and that certain groups of people were more likely to get it.
Speaking to GMB hosts Kate Garraway and Adil Ray, she explained why the elderly are most vulnerable to being affected by the heat.
She also revealed that babies and menopausal women were also most likely to struggle and suffer in the heat.
Sarah said on the show: "Older people are at a much higher risk because they're not aware when they become dehydrated.
"They're more at risk of heatstroke and heat exhaustion. Babies [too].
"Also of course at this time, give a thought to menopausal women. There's an awful lot of them out there, and night sweats as well as hot flushes are a real thing.
"They are only too used to being able to have different layers that they can throw off at night, and putting sheets in the fridge or freezer in a plastic bag and bringing them out earlier."
She added: "For them I think this is gonna be a real issue."
Earlier on in the show, Sarah revealed that high evening temperatures would stop a common hack to cool down our homes from working.
She said: "For a lot of people the heatwave can be tricky, particularly at night.
"One of the big problems we have got is the temperature is not going down at night.
"Most people, even if they find it very hot during the day, we always say keep your curtains shut during the day and then as soon as it gets cooler, you open your windows and curtains to cool things down.
"We can't really do that anymore as it is constantly so hot at night."
On Tuesday, discussing what hacks you could follow, Sarah said: "[The viewers] stole my idea about the cold hot water bottles, but please don't forget; never put ice directly onto your skin because that can cause ice burns.
"But a cool flannel around your neck, and possibly putting sheets in the freezer, but not again risking any ice burns, can help."
Good Morning Britain airs weekdays at 6am on ITV.
