Last updated on 7-7-2025 by Thérésa Lebacq
Why do we study the total water (nutrient) intake?
- Water is vital for the body to function properly, as it makes up about 50% to 70% of body weight and up to 75% in children.
- It plays a key role in regulating body temperature, lubricating joints, protecting organs, transporting nutrients, supporting digestion, and eliminating waste through urine, stool; sweat and breath functions.
- The body continuously loses water through these processes which must be compensated through fluid intake.
- Water intake mostly comes from food, water, and other beverages.
- Water requirements can vary depending on factors such as age, physical activity level, and environmental temperature. For example, needs increase during intense physical activity or in hot climates.
- Drinking sufficient amount of water is essential for maintaining overall health. Recommendations for the adequate daily water intake are set by the European Food Safety Authority (EFSA).
How do we study it?
- Habitual intake of water (nutrient) was analysed using the SPADE® program. The detailed methodology can be found here.
- Habitual water (nutrient) intake is expressed in grams per day.
- To assess whether the intake in the population is adequate, the distribution of the total water (nutrient) intake was evaluated against the dietary reference values set by EFSA: an adequate intake (AI) of:
- 1300-1600 g/day for children depending on age;
- 2100-2500 g/day in adolescent boys and 1900-2000 in adolescent girls;
- 2500 g/day in adult men and 2000 g/day in adult women.
KEY RESULTS
The mean water (as nutrient) intake in Belgium is 2130 g/day
Men (2256 g/day) have higher mean water intake than women (2007 g/day)
Wallonia (2033 g/day) have lower mean water intake than Flanders (2177 g/day)
There is no significant change in the mean water intake between 2014-2015 and 2022-2023
The three main sources contributors of water (nutrient) in the diet are non-alcoholic beverages, vegetables and dairy products and substitutes.
By age and sex
Mean water (nutrient) intake (g/day) in the population aged 3 years and older, by age and sex, Belgium: 2022-2023
- Crude = results weighted for season, age, sex, and socioeconomic status.
- Older adults (65 years and above) do not include those residing in care facilities, hospitalised individuals, or those who would have required significant assistance during interviews (e.g., people with cognitive impairments).
- The mean water (nutrient) intake in Belgium is 2130 g/day
- Overall, men (2256 g/day) have higher mean water intake compared to women (2007 g/day), a pattern that holds true across all age categories.
- Mean water intake increases with age, from children to young adults. Specifically, it increases from an average of 1446 g/day in children aged 3-9 years to a peak of 2313 g/day in younger adults aged 18-64 years. The mean water intake however drops to 2130 g/day in older adults aged 65 and older.
- Among the different age and sex groups, the mean water intake is lowest for girls aged 3-9 years at 1400 g/day, while is highest for men aged 18-64 years, at 2468 g/day.
Comparison of the water (nutrient) intake in the population aged 3 years and older with the adequate intake value, by age and sex, Belgium: 2022-2023
- The results do not allow us to determine whether water intake for children, adolescents and men aged 18 years and older is adequate. Therefore, the possibility of inadequate intake cannot be ruled out.
- Women aged 18 years and older have an adequate water intake.
By educational level
Mean water (nutrient) intake (g/day) in the population aged 3 years and older, by educational level, Belgium: 2022-2023
- Crude = results weighted for season, age, sex, and socioeconomic status.
- The educational level is calculated at the household level by considering the highest diploma obtained by: (i) the respondents or their partner for adults (aged 18 years and above), or (ii) the father and mother (or carer, if applicable) for children and adolescents (aged 3 to 17 years). However, for simplicity, we refer to the educational level of individuals rather than the educational level of their households.
- Individuals with low educational level have the lowest mean water intake at 2057 g/day while those with high educational level have the highest mean water intake at 2207 g/day.
Comparison of the water (nutrient) intake in the population aged 3 years and older with the adequate intake value, by educational level, Belgium: 2022-2023
- The results for this subgroup do not allow us to determine whether water intake is adequate. Therefore, the possibility of inadequate intake cannot be ruled out.
By region
Mean water (nutrient) intake (g/day) in the population aged 3 years and older, by region, Belgium: 2022-2023
- Crude = results weighted for season, age, sex, and socioeconomic status.
- Brussels is excluded from the regional comparison due to an insufficient number of participants, but is included in the national data for Belgium.
- Individuals from Wallonia (2033 g/day) have a lower mean water intake than those from Flanders (2177 g/day).
Comparison of the water (nutrient) intake in the population aged 3 years and older with the adequate intake value, by region, Belgium: 2022-2023
- The results for this subgroup do not allow us to determine whether water intake is adequate. Therefore, the possibility of inadequate intake cannot be ruled out.
By year
Mean water (nutrient) intake (g/day) in the population aged 3 to 64 years, by year, Belgium: 2022-2023
- Crude = results weighted for season, age, sex, and socioeconomic status.
- Adults aged 65 years and older are not included as they were not part of the target population of the 2014-2015 survey.
- There is no significant change in the mean water intake in the Belgian population between 2014-2015 and 2022-2023.
Comparison of the water (nutrient) intake in the population aged 3 years and older with the adequate intake value, by year, Belgium: 2022-2023
- The results for this subgroup do not allow us to determine whether water intake is adequate. Therefore, the possibility of inadequate intake cannot be ruled out.
- Women aged 65 years and above have a low risk on inadequate intake of omega-3 fatty acids.
- However, the results do not allow us to determine whether the intake of omega-3 fatty acids by the general population aged 3 years and above is adequate. Therefore, the possibility of inadequate intake cannot be ruled out.
Contribution of foods to water intake
Contribution of foods to water (nutrient) intake, in the total population aged 3 years and older, Belgium: 2022-2023
- Crude = results weighted for season, age, sex, and socioeconomic status.
- Over 61% of the populations’ water intake comes from non-alcoholic beverages, followed by vegetables and dairy products and substitutes, each contributing around 7%. Fruits and alcoholic beverages account for 5% and 4%, respectively of the populations water intake.
Please cite this page as: Sciensano. Macronutrients: Water, Food Consumption Survey 2022-2023, June 2025, Brussels, Belgium, https://www.sciensano.be/en/results-national-food-consumption-survey-2022-2023/macronutrients/water