Surviving the Heat – The Best Tips for Hot Days and High Temperatures

Hot summers and heatwaves are becoming more frequent – and at high temperatures the body works hard to keep its core temperature stable. Anyone who understands how the body's own cooling works, who is particularly at risk and what really matters when it comes to fluids, minerals and nutrition will get through the hot season more comfortably and in better health. This guide summarises what current research shows – and offers practical tips for hot days.

How the body regulates heat – and where its limits lie

The human body keeps its core temperature within a narrow range around 37 °C. As the ambient temperature rises, thermoregulation kicks in: the blood vessels in the skin dilate so that more heat is released to the outside, and the sweat glands produce sweat, whose evaporation cools the skin. Both mechanisms cost the circulation effort – the heart has to work harder, and with sweat the body loses fluid and minerals.

During prolonged heat, high humidity or physical exertion, this system reaches its limits. When evaporation can no longer dissipate enough heat – for example in humid air – body temperature rises. This brings the risk of heat exhaustion and, in extreme cases, the life-threatening heat stroke.

Why some people are particularly sensitive to heat

Not everyone copes with heat equally well. A systematic review (Núñez-Rodríguez et al., Healthcare, 2025) summarises why older people are particularly at risk: with age, sweat production and the ability to dilate blood vessels decline, cardiovascular adjustment becomes more sluggish and the sense of thirst diminishes. The result is slower cooling, a faster rise in body temperature and a higher risk of dehydration. The review also confirms a clear epidemiological link between high temperatures and increased hospital admissions and deaths among older people – particularly women, the very old and those with pre-existing conditions.

Young children, pregnant women, the chronically ill and people who work outdoors are also among the risk groups. Children have a larger skin surface relative to their body weight and a less mature temperature regulation system – they dehydrate faster.

Fluids and electrolytes – why water alone is not always enough

Drinking enough is the most important measure in the heat. Yet dehydration is widespread, especially among older people: a review (Pence et al., Nutrients, 2025) points to a meta-analysis showing that nearly one in four older people is dehydrated – in care facilities even one in three. Since the sense of thirst declines with age, drinking regularly is more important than waiting for thirst.

With heavy sweating, the body loses not only water but also electrolytes – above all sodium, potassium and magnesium. These minerals control fluid balance and muscle and nerve function. Anyone who sweats a lot should replace the loss. This is usually best achieved through diet: mineral-rich vegetables and fruit, a pinch of salt in food, unsweetened drinks. Heavily sugared sports drinks are rarely necessary for everyday life and can even slow gastric emptying.

Cooling foods and plants for hot days

Diet can contribute a great deal to wellbeing in the heat – above all through water-rich, light and mineral-rich foods. They provide fluid and electrolytes at the same time and burden the metabolism less than heavy, fatty meals.

Herbs play a role too: peppermint provides a refreshing mouthfeel, and unsweetened herbal or fruit teas are a sensible alternative to sugary drinks. A cool cucumber-yoghurt soup, a vegetable gazpacho or a salad with mint are classic summer dishes that combine fluid, minerals and lightness.

Recognising heat exhaustion and heat stroke

It is important to know the warning signs of overheating – and the difference between heat exhaustion and the more dangerous heat stroke.

At signs of heat stroke – confusion, impaired consciousness, very high body temperature – call the emergency services immediately and begin cooling. Heat stroke is a medical emergency.

Practical tips for hot days

• Drink regularly – spread over the day, not only when thirsty. Water and unsweetened teas are ideal.
• Avoid the heat – schedule activities for the cooler morning and evening hours, avoid the midday heat.
• Keep your home cool – ventilate at night and early morning, darken and keep windows closed during the day.
• Eat light – several small, water-rich meals instead of heavy food.
• Airy clothing – loose, light-coloured, breathable; headwear and sun protection outdoors.
• Look out for others – older people, children and the chronically ill need particular attention.

Conclusion

Heat challenges the body – but with the right behaviour the hot season can be managed well. What matters is drinking regularly, replacing electrolytes through a light, plant-rich diet, avoiding the worst of the midday heat and keeping a cool home. Older people and other risk groups, whose temperature regulation works less well, deserve particular attention. Knowing the warning signs of overheating means being able to react correctly in an emergency.

This article is intended for general information and does not replace medical advice. At signs of heat stroke – confusion, impaired consciousness, very high body temperature – call the emergency services immediately.