Why You Feel More Tired in Summer: 5 Causes of Summer Fatigue and How to Feel More Energised

Summer fatigue is common, but simple lifestyle changes can help you beat tiredness during hot weather

When summer arrives, many people expect to feel happier, healthier, and more energetic. Longer days, warmer weather, holidays, and more time outdoors are often associated with feeling refreshed. However, many people experience the opposite. Instead of feeling energised, they feel unusually tired, sluggish, and drained.

This phenomenon is often referred to as summer fatigue, and it can happen for several reasons. Changes in temperature, disrupted sleep patterns, dehydration, allergies, and increased alcohol consumption can all affect how well your body functions during the warmer months.

Medical doctor and wellness expert explains that summer tiredness is not unusual. The body has to constantly adapt to environmental changes, and these adjustments can use energy. If you are wondering why you feel exhausted despite enjoying sunny weather, these five common causes may explain it.

1. Hot Weather Can Leave You Feeling Exhausted

Heatwaves and rising summer temperatures can put extra stress on the body. Your body works hard to maintain a stable internal temperature, and when the weather becomes extremely warm, this process can affect your energy levels.

The human body functions best within a narrow temperature range. When temperatures rise significantly, the body needs to use additional energy to cool itself down. This can leave you feeling tired, slow, and less focused.

One way to reduce heat-related fatigue is to help your body cool down naturally. Cooling areas such as your palms, forehead, and the soles of your feet can help lower body temperature more effectively.

Try using a cool, damp cloth on these areas or placing your feet in cool water. The goal is to cool the body gradually rather than using extremely cold temperatures, which can cause blood vessels to tighten and reduce the cooling effect.

Other ways to manage heat fatigue include:

• Staying indoors during the hottest part of the day
• Wearing lightweight, breathable clothing
• Keeping your home cool and well ventilated
• Taking regular breaks when exercising outdoors

2. Dehydration Can Reduce Energy Levels

One of the most common causes of summer tiredness is dehydration. Hot weather increases sweating, which means your body loses more fluid than usual. If you do not replace those fluids, even mild dehydration can affect your physical and mental performance.

Many people wait until they feel thirsty before drinking water. However, thirst is actually a late warning sign that your body needs more fluids.

Even mild dehydration can contribute to:

• Low energy
• Headaches
• Dizziness
• Difficulty concentrating
• Feeling generally unwell

A simple way to monitor hydration is to check the colour of your urine. Pale yellow usually indicates good hydration, while darker shades may suggest that you need to drink more water.

During hot weather, make a habit of drinking regularly throughout the day rather than relying only on thirst. If you are exercising, spending time outdoors, or sweating heavily, you may need additional fluids.

3. Alcohol Can Affect Summer Sleep Quality

Summer often brings more social events, holidays, outdoor gatherings, and celebrations. As a result, some people drink alcohol more frequently during the warmer months.

Although a drink may help you relax, alcohol can interfere with the quality of your sleep. You may fall asleep quickly after drinking, but your sleep can become less restorative, leaving you tired the next morning.

Poor sleep caused by alcohol may lead to:

• Feeling tired after waking up
• Reduced concentration
• Lower mood
• Less energy during the day

This does not mean you must completely avoid alcohol. However, keeping consumption moderate and avoiding drinking close to bedtime can help protect your sleep quality.

If you notice that you regularly wake up feeling exhausted after summer evenings involving alcohol, reducing your intake may make a noticeable difference.

4. Longer Summer Days Can Disrupt Your Sleep Routine

One of the best things about summer is the extra daylight. However, those longer evenings can also interfere with your body’s natural sleep rhythm.

Your circadian rhythm is your internal clock that helps regulate when you feel awake and when you feel sleepy. Exposure to bright light late in the evening can delay the signals that tell your body it is time to rest.

Early sunrises can also make it harder to sleep in, especially if your bedroom receives lots of morning sunlight.

To improve summer sleep, consider:

• Using blackout curtains
• Wearing an eye mask
• Keeping your bedroom cool
• Following a consistent bedtime routine
• Reducing bright light exposure before sleep

You do not need to avoid summer evenings completely, but creating a darker and calmer sleeping environment can help your body maintain a healthier rhythm.

5. Hay Fever Symptoms Can Make You More Tired

For many people, summer means increased pollen levels and uncomfortable allergy symptoms. Hay fever can cause sneezing, itchy eyes, congestion, and difficulty breathing, all of which can interfere with sleep.

A blocked nose can make it harder to breathe comfortably during the night. Poor-quality sleep caused by allergies may leave you feeling tired even if you spend enough hours in bed.

Managing hay fever symptoms can help improve your sleep. Helpful strategies may include:

• Keeping windows closed when pollen levels are high
• Washing your face and hair after being outdoors
• Changing bedding regularly
• Using suitable allergy treatments recommended by healthcare professionals

Some people also find nasal strips or saline nasal rinses helpful for improving airflow through the nose.

How to Beat Summer Fatigue Naturally

Feeling tired in summer does not always mean something is wrong. Often, your body is responding to changes in temperature, light exposure, routines, and lifestyle habits.

Small adjustments can make a big difference. Stay hydrated, protect your sleep, manage allergies, avoid excessive alcohol, and take steps to stay cool during hot weather.

If tiredness is severe, lasts for a long time, or affects your daily life, it is worth speaking to a healthcare professional to rule out other possible causes.

Summer should be a season for enjoying life, not constantly fighting exhaustion. Understanding what causes summer fatigue can help you make simple changes and feel more energised throughout the warmer months.

Source: The Independent (23 July 2026)e.

Disclaimer: This article is for general informational purposes only and does not replace professional medical advice, diagnosis, or treatment. If you have ongoing or unexplained fatigue, speak with a qualified healthcare professional. Individual health needs vary, and advice from a doctor or specialist should be followed where appropriate.