Like carbohydrates, lipids, proteins, vitamins, and minerals, water is an essential nutrient for the human body. The main sources of water for the body obviously include water itself, but also other beverages such as tea and coffee, as well as foods, especially fruits and vegetables. However, throughout the day, the body loses water through urine and stool, as well as through breathing, skin, and sweat. This water loss can lead to dehydration and symptoms such as dry mouth, headaches, and difficulty concentrating. It is therefore important to regularly replace water losses during the day to reduce the risk of dehydration.
How much water should we consume daily?
The amount of water to drink each day varies depending on several factors such as physical activity level, age, and sex, but also ambient temperature and humidity, as well as the presence or absence of certain symptoms such as fever, vomiting, or diarrhea.
In Canada, recommendations are presented in the form of adequate intakes (AI). These take into account total water intake, which includes drinking water and water provided by beverages and foods. The recommended AI for total water for women aged 19 and over is 2.7 L/day and 3.7 L/day for men in the same age group. The recommended AI increases to 3 L/day for pregnant women and 3.8 L/day for those who are breastfeeding. However, water and beverages generally represent the majority of intake for most individuals. Excluding foods, the recommended AI for women aged 19 and over is 2.2 L/day and 3 L/day for men in the same age group. The recommended AI increases to 2.3 L/day for pregnant women and 3.1 L/day for those who are breastfeeding.
Finally, as mentioned earlier, other factors besides age and sex influence the amount of water needed. For example, daily needs increase with physical activity, ambient temperature, and the presence of fever, vomiting, and diarrhea. Since water losses are increased in these situations, additional water intake is necessary to replace them and maintain an adequate hydration level.
Which beverages contribute to total water intake?
Several beverages can contribute to total water intake. This includes beverages such as tea, herbal tea, coffee, milk, plant-based drinks, juices, etc. However, there are a few points to consider before choosing a beverage, including free sugar, caffeine, and alcohol content.
First, it is important to pay attention to the free sugar content of different beverages. Free sugars include monosaccharides (e.g., glucose, fructose) and disaccharides (e.g., sucrose or table sugar) added to foods and beverages, as well as sugars naturally present in honey, syrups, fruit juices, and fruit juice concentrates (WHO, 2015). For health, the World Health Organization (WHO) recommends limiting free sugar intake to 50 grams (4 tablespoons) per day. According to WHO, it would be even better for health to reduce free sugar intake to 25 grams (2 tablespoons) per day. Knowing that beverages such as iced teas, fruit juices, chocolate milk, soft drinks, and energy drinks can contain a high amount of free sugars, it is preferable to limit their consumption and replace them with water or unsweetened tea, herbal teas, and coffee daily.
Second, attention should be paid to the caffeine content of caffeinated beverages. Beverages like tea and coffee are mainly composed of water and are good sources of hydration. Indeed, research does not confirm that caffeine has a diuretic effect leading to dehydration. Studies observe that beyond 180 mg per day, it can transiently increase urination in some people, but not necessarily lead to dehydration. Therefore, caffeinated beverages, such as tea and coffee, contribute to total water intake. However, some beverages, like energy drinks, can contain a high amount of caffeine. As a reminder, Health Canada recommends limiting caffeine consumption to 400 mg per day for adults, about eight cups of tea or two to three cups of coffee, and to 300 mg per day for pregnant or breastfeeding women, about six cups of tea or one to two cups of coffee.
Finally, the alcohol content of alcoholic beverages is another important aspect to consider. Indeed, alcohol facilitates water elimination by the body by suppressing arginine vasopressin, an antidiuretic hormone that signals the kidneys to reduce urination and reabsorb water in the body. Therefore, alcoholic beverages can increase the risk of dehydration and do not count among beverages that contribute to total water intake. If you drink alcoholic beverages, it is recommended to consume them in moderation, with food, and alternate with water to reduce the risk of dehydration.
Some tips to drink more water
Water should be the beverage of choice daily. However, some people may have difficulty consuming enough. Here are some tips to drink more:
- Drink a glass of water upon waking.
- Always have a reusable water bottle with you.
- Flavor your water with fruits, cucumber, lime, lemon, fresh herbs, etc.
- Drink water during meals.
- Drink unsweetened herbal tea, tea, or coffee.
- Use an app to track your daily water intake.
- Be attentive to dehydration symptoms: thirst, dry mouth, headaches, dark yellow urine, etc.
References
- https://www.canada.ca/content/dam/hc-sc/migration/hc-sc/fn-an/alt_formats/hpfb-dgpsa/pdf/nutrition/dri_tables-fra.pdf
- https://www.nchpad.org/1242/5916/Water~~The~Essential~Nutrient
- https://www.unlockfood.ca/fr/Articles/Eau/L-hydratation,-ca-coule-de-source.aspx?aliaspath=%2fen%2fArticles%2fWater%2fFacts-on-Fluids-How-to-stay-hydrated
- https://www.hsph.harvard.edu/nutritionsource/water/
- https://www.nap.edu/read/10925/chapter/6#134
- https://www.hsph.harvard.edu/nutritionsource/healthy-drinks-full-story/
- https://www.hsph.harvard.edu/news/hsph-in-the-news/the-importance-of-hydration/
- https://www.cdc.gov/healthyweight/healthy_eating/water-and-healthier-drinks.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fhealthywater%2Fdrinking%2Fnutrition%2Findex.html
- https://www.unlockfood.ca/fr/Articles/Cafeine/Jusqu’a-la-derniere-goutte!.aspx