Guidelines for Hydration Management

Some people completely overlook the importance of proper hydration, while others focus excessively on calculating the exact amount of fluids needed for optimal functioning. Adults have the ability to rely on their own feelings to tell them when they need to drink due to fluid deficiency. However, relying on this indicator for children is problematic, and for infants and toddlers, it is even impossible. Children are much more sensitive to water loss than adults. Their body water percentage during this period is significantly higher (75-80%) than in the adult population (55-60%), for example, a loss of 10% of body weight (0.5 kg for a child weighing 5 kg) is already a health-critical situation. It is therefore advisable to monitor fluid intake, with the understanding that the generally recommended fluid intake volume, which depends on age and body weight, is not a guarantee of optimal levels. Situations that significantly increase the need for fluid intake occur in everyone's life, and small children are no exception.

The following rules generally apply to hydration:

1. Infant Period.

During the first 6 months of life, fluid intake is adequately ensured through breastfeeding or formula feeding. Under normal temperature conditions, it is recommended not to offer additional fluids (water, teas, milk...). In hot weather, when the risk of dehydration increases, it is sensible to slightly increase the fluid intake. Teas are presented as suitable, but always fruit teas, not green or black. We do not add sugar to tea, and we always prefer infant-quality water as a source of hydration.

2. Period of Introducing Complementary Foods.

Standard hydration recommendations for the age category of 7-12 months aim for 100–140 ml of fluids per 1 kg of body weight. For a child weighing 8 kg, this means at least 800 ml of fluids, where the quality should also be considered:

It is commonly recommended to provide approximately 500 ml of milk (preferably breast milk), which besides fluids will also ensure an important amount of proteins and calcium. The rest should be high-quality (infant) water, or teas (fruit and herbal). It is important for the child to take in fluids at regular intervals throughout the day and not in large amounts all at once.

3. Preschool Period.

At this age, recommendations guide to 80-120 ml per 1 kg of body weight. The proportion of milk in the total fluid intake decreases, but some debates on its intake persist due to the need for adequate calcium (replacement with fermented products, such as yogurts, seems more beneficial). This period is also characterized by the child's ability to express thirst. This is very important as it eliminates the need for parents to strictly monitor fluid intake, reducing the risk of dehydration, which is typically characterized by increased fatigue, headache, or decreased urine production. 

Since today's market is inundated with an overwhelming variety of drinks that also target the children's population, there is a common dilemma regarding which fluids are most suitable:

For infants and toddlers, it is unequivocally infant-quality water. From this, teas are prepared, preferably fruit teas for the youngest, and suitable herbal teas for older children. It is always preferable not to add sugar.

As children grow older, there are recommendations to also include mineral waters. However, it is important to avoid carbonated (CO2) ones and simultaneously consider whether there is any benefit in burdening the metabolism with unnecessarily high doses of inorganic mineral salts.

Preschool-age children enjoy consuming sweetened drinks. The most suitable option is juices - but always without sweeteners, colorings, and other additives, ideally diluted with water.

Drinks that are clearly unsuitable include:

• sweetened and carbonated drinks,
• drinks containing stimulant substances, most commonly caffeine (black tea, coffee, mate...)
• drinks containing quinine,
• drinks containing alcohol,
• energy drinks (even those with concentrated amounts of vitamins).

The suitability of green tea is often debated. It is presented as a "healthy" liquid due to its content of antioxidant substances. However, it is also a source of caffeine, albeit in relatively small amounts. Children at least up to 1 year should avoid it; for older age categories, it can be a regular part of their fluid intake.

A responsible parent should be aware that in situations of increased physical activity or when in a hot or excessively dry environment, the fluid requirement increases significantly, often to more than double the basic recommended amount. The same applies during illnesses accompanied by elevated body temperature.