What to Eat and Drink During a Heatwave to Stay Cool and Nourished
Skip the heavy meals and sweltering oven. Discover which foods and drinks will keep you cool, hydrated, and energized when temperatures soar.
Eating Smart When the Temperature Rises
When a heatwave hits, the last thing most people want to do is stand over a hot stove — and appetite often takes a nosedive too. But does extreme heat actually call for a change in what we eat? Nutrition experts say yes, and the adjustments are simpler than you might think.
Here are four key things to keep in mind when you're hot, hungry, and looking for relief.
1. Should You Eat More Protein in a Heatwave?
The short answer is no. According to Aisling Daly, senior lecturer in nutrition at Oxford Brookes University, there is no increased need for protein during a heatwave.
What's more, protein-rich foods like meat, poultry, and fish typically require cooking — which is the last thing anyone wants to deal with in scorching heat. Even firing up an outdoor BBQ can feel unbearable.
Smarter Ways to Cook When It's Hot
If you do need to cook, consider reaching for your air fryer. Research from Radio 4's Sliced Bread found that air fryers use less than half the energy of a conventional oven. They're also smaller and faster, meaning they generate significantly less ambient heat in your kitchen.
Don't overlook your slow cooker either. Despite running for longer periods, slow cookers are typically more energy-efficient and produce even less heat than air fryers — making them a surprisingly smart choice during a hot spell.
Why Protein Actually Heats You Up
Here's a lesser-known fact: digesting protein causes your body to generate more internal heat than digesting carbohydrates or fats. That's because the stomach, intestines, and liver have to work harder to break down and absorb complex protein molecules — a process that produces heat as a byproduct.
In other words, that sizzling steak might leave you feeling even hotter. Opt for fruits, vegetables, and carbohydrates instead, as they're far easier to digest.
Best Protein Options for Hot Weather
Dr. Daly recommends leaning on pre-cooked meats, bean salads, eggs, and Greek yogurt — which can even be enjoyed frozen. Blending a smoothie with fruit, vegetables, yogurt, and a spoonful of peanut butter is an easy way to get a nutritious, balanced meal without breaking a sweat.
Lighter fish options like tuna, salmon, and prawns are also excellent choices. Vegetarians can meet their protein needs through lentils, nuts, milk, tofu, and cheese.
2. Hydration Is Everything — But It's Not Just About Water
When temperatures climb, your body loses water through sweat at a much faster rate. Failing to replace that fluid leads to dehydration, which can quickly become dangerous.
The NHS typically recommends six to eight glasses of fluid per day, but during a heatwave, your requirements can increase substantially. Dr. Charlotte Mills, a food and nutrition scientist at the University of Reading, notes that individual fluid needs vary widely based on age, body size, activity level, and overall health.
Athletes, pregnant women, and breastfeeding mothers are among those who need to be especially vigilant about staying hydrated.
Eat Your Water
Rehydration isn't limited to what's in your glass. As Dr. Daly explains, "We need to eat our water as well as drink it" — and most fruits and vegetables are between 80% and 90% water by weight.
Foods with over 90% water content include:
- Cucumber
- Tomatoes
- Lettuce
- Celery
- Watermelon
- Strawberries
Apples, carrots, cooked broccoli, pears, oranges, grapes, and pineapple all fall in the 80–89% range. By contrast, boiled eggs are about 75% water, while digestive biscuits contain just 2.8%. Even a cheese and tomato pizza is 38% water, and takeaway chips come in at roughly 51%.
How to Tell If You're Dehydrated
A quick and reliable indicator of hydration status is the color of your urine. Dark orange or brown urine signals that your kidneys are conserving water — meaning your body is running low. Feeling fatigued, unfocused, or dizzy are also warning signs. Left unaddressed, heat exhaustion can progress to heatstroke, which is a serious medical emergency.
3. Hot Drinks Can Actually Help Cool You Down
It might seem counterintuitive, but reaching for a warm cup of tea on a hot day is actually backed by science. According to Dr. Daly, warm or room-temperature drinks are just as effective at cooling you down as cold ones.
Research indicates that consuming a hot drink prompts your body to sweat more rapidly in order to shed the excess heat. Cold drinks, on the other hand, slow down the sweating response. Either way, your body is working to maintain its core temperature at around 37 degrees Celsius — so that beloved cup of tea might not be such a strange choice after all.
Final Takeaway
Navigating a heatwave doesn't mean abandoning nutrition — it just means being smarter about what you reach for. Prioritize hydrating foods, keep protein sources light and pre-cooked where possible, and don't underestimate the power of a good smoothie. Your body will thank you for it.
