How much taurine do you need per day?
There is no established daily figure for taurine alone. Anyone who regularly eats fish, meat or dairy is probably getting enough. A supplement is unnecessary for healthy people and is not recommended.
Taurine occurs naturally in fish, seafood and meat. Your body also produces it on its own, from the sulphur-containing amino acids methionine and cysteine. The WHO recommendation of 13 mg per kilogram of body weight per day for healthy adults applies to the sulphur-containing amino acids, the building blocks your body uses to make taurine. No minimum has been set for taurine itself.
How little taurine you can take in is seen most clearly in people who consume none at all. Vegans who had avoided animal products for an average of more than four years had measurably lower taurine levels in the blood than people who did eat them (45 versus 58 micromol per litre), and excreted far less taurine in their urine. Yet no clinical complaints were reported in that small study (12 vegans). Whether a lower blood level is harmful in itself therefore remained unanswered.
In children and adults who receive long-term intravenous nutrition without taurine, deficits accumulate further. In eight children who were studied, retinal measurements were abnormal. Once taurine was added to the nutrition, retinal values improved in three of the four children. This makes clear that taurine must not be absent from fully artificial nutrition. If you have questions about this for yourself or a family member in a hospital setting, discuss them with your doctor.
Taking taurine as a standalone supplement has no proven benefit in healthy people. There is no established figure for how much extra you would need, and apart from long-term intravenous nutrition, supplementation is not recommended. How much extra taurine you can safely take was not studied in this research.
This answer is based on a small observational study in vegans, two studies in patients receiving intravenous nutrition, a WHO dietary guideline and two review articles. The evidence is narrow and predominantly older. The researchers measure blood values and excretion, but in most cases no hard health outcomes. For healthy people who eat normally, there is very little research into what an optimal taurine intake looks like.
How much lithium do you need each day?
There is no official daily recommendation for lithium; scientists cite 1 mg per day as a cautious guideline, but evidence for benefits in healthy people is largely absent, so supplementation is not yet substantiated.
How much green tea do you need per day?
Two to three cups per day is the amount at which most studies show health benefits, but a scientifically established optimal dose does not exist.
How much vitamin D should you take per day?
For healthy adults under 75, extra vitamin D is probably not necessary. For children, adults aged 75 and over, pregnant women, and people at high risk of diabetes, there are indications that supplementation helps, but discuss this with your doctor.
How much water do I really need to drink per day?
There is no magic number: for a healthy adult who is not very active, thirst is a reliable guide, with a total fluid intake of roughly 2 to 3 litres per day from all sources as a reference point. Drink more as soon as you exercise, when it is warm, or as you get older.
How much iron do you need per day?
For healthy adults without a deficiency, 1 to 2 mg of iron per day through food is sufficient. When a deficiency or anaemia is confirmed, requirements are much higher; discuss that with your doctor.
How many vegetables do you really need per day?
Five servings of vegetables and fruit per day offers the best protection, with non-starchy vegetables counting and juice and potatoes not. More than five servings adds nothing.