Hydration

Headaches, tiredness and poor focus can simply mean you are not drinking enough water, though sometimes thirst is a sign worth checking.

4 min read · Awareness resource · Reviewed 2026-09-26

Feeling tired, headachy or foggy in the afternoon? Before you reach for another coffee or energy drink, check your water. Many people, especially those working outdoors, driving long hours or working in hot kitchens and factories, simply do not drink enough.

What is happening

About half of your body is water, and your brain is sensitive to even mild dehydration. Losing a small amount of body water can cause headaches, tiredness, poor concentration, irritability and a racing heart. In South Africa's hot months, on building sites, farms, mines, taxis or in a tin-roof home, you can lose a lot of fluid through sweat.

There is no single perfect amount. A common guide is about six to eight glasses of fluid a day for most adults, more when it is hot, when you are active, or when you are breastfeeding. Water, rooibos, weak tea and milk all count. Food like fruit, vegetables and soup adds water too. Sugary drinks and energy drinks add fluid, but also a lot of sugar. Alcohol makes you lose more water.

The simplest sign is your urine: pale yellow usually means you are drinking enough; dark yellow means drink more.

Signs to notice

Dark yellow urine, or passing urine only a few times a day
Headaches that ease after drinking water
Dry mouth, lips and feeling thirsty
Feeling tired, dizzy or foggy, especially in the afternoon
Muscle cramps during work or exercise
Constipation

30-second self-check

Answer yes or no for a typical day.

Is your urine usually dark yellow?
Do you often go more than three hours without drinking anything?
Do you drink fewer than four glasses of fluid on most days?
Do you work or travel in heat without easy access to water?
Do you get afternoon headaches or brain fog?
Do you drink more than two sugary or energy drinks a day?
Do you drink alcohol on most days?

0-1 yes: You are probably drinking enough. Keep it up, especially on hot days.
2-3 yes: You may be mildly dehydrated at times. Build a few water habits into your day.
4 or more yes: Dehydration may be affecting your energy and mood. Start small and steady, and talk to a nurse if you still feel unwell.

What you can do next

Today: Drink a glass of water when you wake up and with every meal.
This week: Carry a refillable bottle. A washed 2-litre cooldrink bottle works fine. Refill it at work or school.
This month: Link drinking to habits you already have, such as every taxi ride, each tea break, or each time you check your phone.
If your tap water is unsafe or cuts out, bring it to a rolling boil before drinking, and store it in a clean, covered container.
On very hot days, drink before you feel thirsty and rest in the shade.
Employers of outdoor workers: provide shaded drinking water and regular rest breaks.

Your tool

Lifestyle Health Check - a short self-check across drinking, eating, movement, sleep, alcohol, smoking and stress that shows which small change could help most.

When to get professional help

See a nurse or doctor today if you are always very thirsty and passing a lot of urine, as this can be a sign of diabetes, or if you have had vomiting or diarrhoea and cannot keep fluids down, especially in children, older people or someone who is pregnant. Oral rehydration solution from a pharmacy or clinic helps. Call 10177 or 112 for signs of heat stroke: confusion, fainting, very hot skin, no longer sweating, or a seizure. Move the person into shade and cool them with water while you wait.

Who can help: doctor, nurse, dietitian

Getting help in South Africa

Your local public clinic can check you for dehydration, diabetes and kidney problems and supply oral rehydration sachets. Pharmacies sell rehydration products and can advise. If you have a heart or kidney condition, ask your doctor how much fluid is right for you, as some people need to limit fluids.