In one sentence
Three daily amounts VT works out for you from your size and your goal, shown on the nutrition screen as a guide to log against, not as a prescription.
Protein
Set from your lean mass, or from your body weight when VT has no body-fat reading, and raised when you are in a deficit, training for muscle, or past 40. The reference points are the literature's: the Morton meta-regression found no further gain in lean mass from resistance training above about 1.6 grams per kilogram a day, and a smaller effect of extra protein with increasing age (Morton 2018). VT's figure sits in the range the sports-nutrition literature supports and is labeled with it; the exact rule is in the method section.
Fiber
Set at 14 grams for every 1,000 kcal you burn, from your seven-day energy estimate, which for most adults lands in or above the band where the Lancet series found the largest associations, 25 to 29 grams a day, with its dose-response suggesting more may be better (Reynolds 2019). Many people eat less than that without knowing it, which is why the target is shown at all.
Water
Scaled to your size and shown as a guide. The evidence for a precise daily amount in healthy adults is thin, thirst is a good guide for most people, and the figure is a starting point, raised for the minutes you train; it is not a medical fluid target, and anyone with a condition their doctor manages should take the doctor's figure.
How Vitality Tracker uses it
Shown with your Calories Goal and on the nutrition charts, where the day's protein is drawn against its target; nothing scores you on them.
How far to trust the number
Calculated from your profile through published ranges; the ranges are population findings and your own needs may sit anywhere within or outside them.
Sources
- Morton RW, et al. Br J Sports Med 2018;52:376–84. doi:10.1136/bjsports-2017-097608
- Reynolds A, et al. Lancet 2019;393:434–45. doi:10.1016/S0140-6736(18)31809-931809-9>)
- Vitality Tracker, What VT measures (catalogue of 15 October 2026).