Remember to drink enough in hot weather

It is particularly important that children and elderly people stay adequately hydrated.

Water is the best thirst-quencher. In hot weather, make sure to drink one or two extra glasses of water with meals compared to usual. It is also a good idea to drink a few extra glasses between meals. However, take care not to drink too much fluid. More than five litres a day is generally too much for the body.

More continuous fluid intake is particularly important if the heat causes heavy sweating, for example when doing physical work. If physical exertion is prolonged and sweating is heavy, you can use drinks containing salt.

Why is it important to drink in the heat?

Water is essential for the human body. Water

  • maintains fluid balance
  • regulates body temperature
  • supports digestion
  • supports the transport and absorption of nutrients
  • removes metabolic waste products.

What is good to drink?

Choose as your mealtime drink

  • tap water
  • unsalted mineral water
  • skimmed milk
  • skimmed buttermilk
  • fortified, unsweetened plant-based drink.

If you drink juice with your meals, dilute it. Juices contain a lot of added sugar.

Avoid coffee and alcohol as thirst-quenchers, as they dehydrate the body. If you drink coffee or alcohol, always have a glass of water alongside it. If sweating is heavy, it may be justified to drink a beverage containing a small amount of salt.

Pay attention to your drinking bottle

Single-use bottles are intended to be used only once. For regular use, it is worth choosing a bottle designed for that purpose.

Plastic is a more porous material than glass or metal, which means that when scratched it can collect microbes more readily. Although a plastic bottle does not last as long as a glass or metal one, when used correctly it is a safe choice.

If your drinking bottle becomes damaged or the water stored in it tastes unusual, it is time to replace it with a new one.

Wash your drinking bottle daily

Drinking directly from the bottle increases the number of microbes in the bottle and in the water stored in it. You can avoid the health risks caused by microbes by washing your drinking bottle every day.

  • Use a bottle brush, warm water, and a drop of washing-up liquid.
  • Avoid boiling water, which can damage plastic.
  • Rinse the bottle thoroughly and leave it upside down to dry, so that the inside dries properly.

Fluid tips for different stages of life

Babies and children

  • For a small baby (under 4 months), breast milk or infant formula is generally sufficient as a source of fluid. In hot weather, however, breast milk or formula should be offered to the baby more frequently than usual. It is particularly important for a breastfeeding mother to remember to drink more than usual herself.
  • Once a baby has started solid foods, water can also be given in hot weather. Water can be offered, for example, from a bottle with a teat or a sippy cup.
  • In hot weather, babies should be protected from direct sunlight and heat, as their ability to regulate body temperature is not yet fully developed. Children too should avoid spending long periods in direct sunlight.
  • Under normal conditions, a child needs 1–1.5 litres of fluid per day. In hot weather, fluid requirements may be even higher.
  • Offer children drinks regularly throughout the day.
  • A child has not drunk enough if they are urinating less frequently than usual and their urine is darker in colour than normal. Dehydration can also cause headaches and irritability.

Adults

Pregnant individuals

  • Remember to drink enough, as your blood volume increases during pregnancy and requires more fluid. Adequate hydration supports metabolism, reduces swelling, and helps prevent constipation.
  • In addition to water, recommended drinks include, for example, low-fat or fat-free dairy products and fortified plant-based drinks, which help to ensure adequate intake of nutrients such as calcium, vitamin D, and iodine.
  • Do not drink alcohol. Alcohol can harm the foetus at every stage of pregnancy.

Breastfeeding individuals

  • When breastfeeding, you lose fluid. You should therefore drink roughly the equivalent of the amount of milk you produce. However, drinking more than necessary does not increase the volume of breast milk.
  • Do not drink excessive amounts of fluid. More than five litres per day is clearly too much for the body.
  • Suitable drinks include, for example, water, low-fat or fat-free dairy products, tea, low-sugar diluted juices, and fortified, unsweetened plant-based drinks.
  • Drink coffee in moderation. Excessive coffee consumption may make your baby restless, as some caffeine passes into breast milk.
  • Avoid alcohol whilst breastfeeding. Alcohol leaves breast milk at the same rate as it leaves the blood. Levels are at their highest approximately 30–60 minutes after drinking alcohol.

Older people

  • It is advisable to drink 1–1.5 litres (5–8 glasses) of fluid per day, in addition to the fluid obtained from food. In hot weather, when sweating increases, it is worth drinking a few extra glasses. Drink even if you do not feel thirsty.
  • Good drinks include, in addition to water and dairy products, fortified plant-based drinks, pure fruit juices, fruit drinks, and soft drinks. Eat foods with a high water content, such as salads and cold soups.
  • Keep a litre jug of drink in the fridge every day. This also allows you to monitor how much you are drinking.
  • Drink more fluid in the morning and during the day. Drinking large amounts in the evening increases the need to urinate at night.
  • Dehydration is particularly serious for older people, as the body contains less water than in younger people.
  • Dehydration can develop very quickly. It can lead to, amongst other things, a drop in blood pressure and falls. Some medications also increase fluid requirements.
  • Nutrition recommendations for older people (Finnish Food Authority)