Water [1]
Why do we study the consumption of water according to guidelines?
- A balanced diet plays an important role in maintaining and promoting health. The Superior Health Council provides food-based dietary guidelines [2] tailored to the Belgian population, aiming to reduce illness, premature death, and the overall disease burden caused in part by unhealthy eating habits.
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Water is an essential nutrient, involved in almost every function of the human body. Water is the main component of the human body, accounting for around 60% of the weight of an adult male and 50-55% of the weight of an adult female. Water plays a particularly important role in thermoregulation and appropriate hydration. Drinking “plain” water provides essential fluid intake without the calories. Depending on its mineral content, water can also contribute to calcium, magnesium and sodium intakes.
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Total water intake (i.e. water from food and drink) should be 2 litres per day for adult women and 2.5 litres for adult men. Since adults take in about 1 to 1.5 litres of water a day from food, they should drink 1 to 1.5 litres of beverages per day. Water is preferable, but coffee and tea without added sugar and/or sweeteners can also be included.
How do we study the consumption of water?
- Trained interviewers conducted two non-consecutive 24-hour dietary recalls to record all the foods and drinks participants had consumed on the previous day. These recalls were carried out in a standardised manner using a specialised computer program (GloboDiet®).
- The intake of water was assessed as habitual intake (also known as usual or long-term intake), representing the average daily intake over the long term. This method accounts for natural day-to-day variations in what and how much people eat, offering a more accurate picture of typical dietary habits over time. This is particularly important when evaluating whether a population meets dietary recommendations. All intakes mentioned in the results below refer to the mean habitual intake, unless stated otherwise.
- The statistical tool Statistical Program to Assess habitual Dietary Exposure (SPADE) was used to estimate habitual intake distributions based on the short-term data collected through the 24-hour dietary recalls.
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Only water intake was evaluated, not water including coffee or tea without added sugar and/or sweeteners, due to limitations in the collection of the sugar content of coffee and tea.
- The detailed methodology can be found here [3].
What did we include as “water”?
- Based on the recommendation of the Superior Health Council, “water”:
- includes tap water and spring or mineral water (carbonated or non-carbonated);
- does not include flavoured water without added sweeteners or sugars, or water added in recipes.
KEY RESULTS
The population aged 3 years and older in Belgium drinks on average 896 ml of water per day
63% of adults aged 18 years and older drink less than 1 litre of water per day
Children and older adults drink less water than adolescents and adults aged 18-64 years
The proportion of adults aged 18-64 years drinking less than 1 litre of water per day has decreased between 2014-2015 and 2022-2023
The proportion of adults aged 18 years and older drinking less than 1 litre of water per day is higher in Flanders than in Wallonia
By age and sex
Mean habitual intake of water (ml/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.
- Mean intake refers to the estimated mean habitual intake, calculated from two non-consecutive 24-hour dietary recalls.
- 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).
- In Belgium, the mean intake of water is 896 ml/day among the population aged 3 and older. The median intake is 822 ml/day.
- Overall, the mean water intake is the same for women (896 ml/day) and men (895 ml/day). However, among adolescents, boys drink more water (991 ml/day) than girls (898 ml/day). In contrast, among older adults aged 65 years and above, women drink more water (770 ml/day) than men (643 ml/day).
- The mean water intake is higher for adolescents aged 10-17 years (946 ml/day) and adults aged 18-64 years (987 ml/day) than for children aged 3-9 years (715 ml/day) and older adults aged 65 years and above (712 ml/day).
Proportion of the population aged 18 years and older drinking less than 1 litre of water per day, by age and sex, Belgium: 2022-2023
- Crude = results weighted for season, age, sex, and socioeconomic status.
- Children (3–9 years) and adolescents (10–17 years) are not included, as the dietary guideline set by the Superior Health Council applies only to adults.
- 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).
- Two third (63%) of the adults in Belgium drink less than 1 litre of water per day.
- Overall, this proportion is similar for men and women (63%). However, among older adults aged 65 years and above, men are more likely to drink less than 1 litre of water per day compared to women (84% versus 75%).
- Older adults aged 65 years and above (79%) are more likely than adults aged 18-64 years (57%) to drink less than 1 litre of water per day.
By educational level
Mean habitual intake of water (ml/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.
- Mean intake refers to the estimated mean habitual intake, calculated from two non-consecutive 24-hour dietary recalls.
- 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.
- The mean water intake in the population aged 3 years and older is lower for people with a low level of education (814 ml/day) than for those with a medium (931 ml/day) or high level of education (976 ml/day).
Proportion of the population aged 18 years and older drinking less than 1 litre of water per day, by educational level, Belgium: 2022-2023
- Crude = results weighted for season, age, sex, and socioeconomic status.
- Children (3–9 years) and adolescents (10–17 years) are not included, as the dietary guideline set by the Superior Health Council applies only to adults.
- 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.
- The proportion of adults drinking less than 1 litre of water per day is higher among people with a low level of education (70%) than among those with a medium (60%) or high level of education (54%).
By region
Mean habitual intake of water (ml/day) in the population aged 3 years and older, by region, Belgium: 2022-2023
- Crude = results weighted for season, age, sex, and socioeconomic status.
- Mean intake refers to the estimated mean habitual intake, calculated from two non-consecutive 24-hour dietary recalls.
- Brussels is excluded from the regional comparison due to an insufficient number of participants, but is included in the national data for Belgium.
- The mean intake of water in the population aged 3 years and older is higher in Wallonia (957 ml/day) than in Flanders (847 ml/day).
Proportion of the population aged 18 years and older drinking less than 1 litre of water per day, by region, Belgium: 2022-2023
- Crude = results weighted for season, age, sex, and socioeconomic status.
- Children (3–9 years) and adolescents (10–17 years) are not included, as the dietary guideline set by the Superior Health Council applies only to adults.
- Brussels is excluded from the regional comparison due to an insufficient number of participants, but is included in the national data for Belgium.
- The proportion of adults drinking less than 1 litre of water is higher in Flanders (68%) than in Wallonia (56%).
By year
Mean habitual intake of water (ml/day) in the population aged 3 to 64 years old, by year, Belgium: 2022-2023
- Crude = results weighted for season, age, sex, and socioeconomic status.
- Mean intake refers to the estimated mean habitual intake, calculated from two non-consecutive 24-hour dietary recalls.
- Adults aged 65 years and above are not included as they were not part of the target population of the 2014-2015 survey.
- The mean intake of water in the population aged 3 to 64 years old has increased between 2014-2015 (773 ml/day) and 2022-2023 (949 ml/day).
Proportion of the population aged 18 to 64 years old drinking less than 1 litre of water per day, by year, Belgium: 2022-2023
- Crude = results weighted for season, age, sex, and socioeconomic status.
- Children (3–9 years) and adolescents (10–17 years) are not included, as the dietary guideline set by the Superior Health Council applies only to adults.
- Adults aged 65 years and above are not included as they were not part of the target population of the 2014-2015 survey.
- The proportion of adults aged 18-64 years drinking less than 1 litre of water has decreased between 2014–2015 (70%) and 2022–2023 (56%).
Please cite this page as: Sciensano. Food-based dietary guidelines: Water, Food Consumption Survey 2022-2023, October 2025, Brussels, Belgium, https://www.sciensano.be/en/results-national-food-consumption-survey-2022-2023/food-based-dietary-guidelines/water [4]