Does you get all the water you need via food/diet alone?
Check out this answer from Consensus:
While it is possible to obtain a significant portion of daily water needs from food, relying solely on food for hydration may not be sufficient for most people. The combination of water from both food and beverages is essential to meet the body’s hydration requirements. Therefore, it is important to maintain a balanced diet that includes both water-rich foods and adequate fluid intake to ensure optimal hydration and overall health.
Water is an essential component of the human diet, playing a crucial role in various physiological functions. While it is commonly believed that drinking water is the primary way to meet hydration needs, the contribution of water from food is often overlooked. This article explores whether one can obtain all the necessary water through food and diet alone, drawing on findings from recent research studies.
Water from Food vs. Beverages
Research indicates that water intake from food and beverages can have different impacts on health. A study involving Japanese dietetic students found that water intake from foods, but not from beverages, was associated with lower body mass index (BMI) and waist circumference. This suggests that water consumed as part of food may promote satiety and reduce overall calorie intake, potentially aiding in weight management1.
Total Water Intake and Dietary Quality
An analysis of the Australian National Nutrition and Physical Activity Survey revealed that the majority of the population did not meet the Adequate Intake (AI) values for total water intake. The study found that plain drinking water, other beverages, and food moisture contributed 44%, 27%, and 29% of total water intake, respectively, among children and adolescents, and 37%, 37%, and 25% among adults. Higher water intakes were associated with better diet quality, including lower intakes of fat, saturated fat, and free sugars, and higher intakes of dietary fiber, fruits, and vegetables2.
Water Consumption and Weight Loss
Another study focused on middle-aged and older adults found that premeal water consumption could facilitate weight loss when combined with a hypocaloric diet. Participants who consumed 500 ml of water before each meal lost more weight compared to those who did not. This suggests that water consumption before meals can reduce meal energy intake and contribute to weight loss3.
Water Intake in Children and Adolescents
Data from the National Health and Nutrition Examination Survey (NHANES) showed that American children and adolescents generally consumed less than the Adequate Intake for total water. The study also found that plain water intake increased with age, while beverage moisture was positively associated with dietary energy and fat intake. This indicates that while children and adolescents do obtain some water from food, it may not be sufficient to meet their hydration needs4.
Can you get all the water you need via food/diet alone?
Nick Ashton has answered Unlikely
An expert from University of Manchester in Physiology, Nephrology, Cardiovascular Disease, Fasting, Developmental Biology
There are two questions here: can you obtain all of the daily water that you need from your food and should you drink 2 litres of water per day (8×8 glasses)?
The answer to both questions is no.
In order to understand why, we need to think about the ways in which we lose water from the body and how we typically take in water. Bear in mind, these numbers refer to a healthy adult in a temperate climate doing no more than light work (the numbers will increase, for example, in hotter climates or when doing heavy exercise).
The average person makes about 1.5 litres of urine per day and loses around 1 litre as water vapour when breathing air out, in sweat and in faeces. This amounts to around 2.5 litres of water lost per day.
Food typically provides around 1 litre per day and your body generates around 0.3 litres per day as a by-product of normal metabolic processes. Therefore in order to stay in balance (i.e. to match the total amount taken in against the total amount lost) you would need to drink around 1.2 litres per day.
BUT this 1.2 litres of fluid intake does not have to be in the form of pure water, as is often stated. Any beverage will provide you with water, so you do not have to consume your 1.2 litres of fluid per day just in the form of water. Tea, coffee, fruit juice, soft drinks, beer: all provide the fluid that you need.
So, can you obtain all of the water that you need from food alone: probably not.
Do you need to drink 2 litres of water a day: no.