A target that just wouldn't budge
If you've logged your water intake in FunTastyQ Fit, you've probably seen a target that felt more like a challenge than a daily habit. The old formula was simple: 35 ml per kilogram of body weight. For a 70-kilogram person, that came to 2.5 litres; for a 100-kilogram person, it was already 3.5 litres.
The data showed that this wasn't working. Our users drank an average of about one and a half litres a day and reached their target only about once every six days. When you miss your target five days out of six, it stops being motivating. It starts to feel like failure.
The number wasn't wrong, but the tracking method was
35 ml per kilogram is not a wrong number. But it represents all the water your body needs in a day, including the water you get from food. Soup, porridge, fruit and vegetables, yoghurt and even bread contain water. According to the European Food Safety Authority (EFSA), food provides about 20–30% of daily water intake.
The other problem is that water needs do not increase linearly with body weight. Fat tissue contains little water, so a heavier person does not automatically need proportionally more to drink. EFSA recommends a total daily water intake of about 2.0 litres for adult women and 2.5 litres for adult men. Once the amount from food is subtracted, that leaves about 1.6–2 litres to drink.
The new goal: only what you drink
The app now shows a drinking goal based on an updated method, and you only need to log drinks. Here is how it works:
Your basic goal depends on your weight, but always stays between 1.5–2 litres. At 70 kg, it is about 1.6 litres, at 80 kg, 1.8, and from 90 kg upwards, 2 litres.
On training days, half a litre is added for each hour of exercise, up to a total of one litre. The app automatically takes your logged workouts into account and increases your water goal accordingly.
During pregnancy and breastfeeding, the goal is a quarter of a litre and half a litre higher, respectively. The app also shows this automatically.
What counts: water, tea, coffee, milk and juice. Coffee does not dehydrate you, as you may have read somewhere. It is a fluid and counts just like any other drink.
Eight glasses of water is just enough on most days. It is easy to remember and an achievable goal.
Why this is more motivating
A good goal is one you can realistically achieve every day. When the virtual water bottle in the app is full by evening, you get a small sense of achievement, which helps you keep up the habit. If the goal is always out of reach, you soon stop logging altogether.
The new goal also adapts to your day. It is lower on a quiet day and higher on a training day. This way, the number truly reflects what you need today, rather than showing the same large number every day. The same goal is also used to calculate your daily score.
Listen to your body too
The number in the app is a useful guide, not a rule. In hot weather, in the sauna or during a long workout, you sweat more and can naturally drink more, just as your thirst dictates. Pale yellow urine is a sign of good hydration. If you have kidney, heart or other health problems, consult your doctor about how much to drink.
Open FunTastyQ Fit and see your new hydration goal in the daily view →
Source: EFSA, Scientific Opinion on Dietary Reference Values for water (2010).
