Hot weather often leaves us feeling more fatigued than usual as our bodies have to work harder to cool themselves down.

The body’s natural cooling mechanism involves increasing blood circulation near the skin’s surface and promoting sweat production.

These physiological changes can lead to fatigue and a feeling of lethargy and this normal response to heat is typically temporary.

However, doctors are urging people to keep an eye out for warning signs that could indicate medical emergencies.

Dr Zulqarnain Shah, medical director at SSP Health and GP at SSP Health practice Colne Road Surgery, explained: “Hot weather increases the rate of fluid loss through sweating, leading to dehydration. Dehydration can contribute to fatigue and make you feel even more lethargic.

“To avoid this, it’s important to stay adequately hydrated by drinking plenty of fluids, especially water.

“Aim to drink even when you’re not feeling thirsty, as thirst is not always an accurate indicator of dehydration.”

Dr Shah added: “Prolonged exposure to heat can result in heat exhaustion, a condition characterised by symptoms such as heavy sweating, weakness, dizziness, nausea, headache, and muscle cramps.

“If you experience these warning signs, it’s crucial to move to a cooler environment, drink fluids, and rest. If symptoms persist or worsen, seek medical attention promptly.”

It is vital to look out for these warning signs, including headaches, dizziness and nausea, as they can develop into heat stroke, which is a medical emergency.

“Heat stroke is a severe and potentially life-threatening condition that requires immediate medical intervention. It occurs when the body’s temperature regulation fails, and the core temperature rises dangerously high,” said Dr Shah.

“Symptoms may include a high body temperature – above 39.4C, altered mental state, confusion, rapid breathing, rapid heartbeat, and even loss of consciousness. If you suspect heat stroke, call emergency services immediately.”

High temperatures can also lead to a lack of sleep, which is another explanation as to why we often feel more tired during hot weather.

“Hot temperatures can disrupt sleep and lead to poor sleep quality. The body needs to cool down to initiate sleep, and the excessive heat can make it difficult to reach the optimal sleep temperature,” explained Dr Shah.

Dr Shah’s advice to improve sleep in hot weather is to “consider using fans or air conditioning, wearing lightweight and breathable sleepwear, keeping your bedroom well-ventilated, and using lighter bedding”.

Heatwaves and hot weather can worsen and intensify the fatigue often experienced by people living with chronic or long-term health conditions.

Dr Shah concluded: “Hot weather can exacerbate symptoms and increase fatigue in individuals with certain chronic health conditions.

“Conditions such as heart disease, kidney problems, and respiratory issues can be particularly sensitive to heat.

“It’s vital to be aware of your specific health condition and consult with your healthcare provider for personalised advice on managing your symptoms during hot weather.

“They may recommend staying in cooler environments, adjusting medications, or monitoring your fluid intake more closely.”

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