Research Measurements
NNT
Number Needed to Treat
How many people need to take a supplement for one additional person to benefit.
Number needed to treat (NNT) expresses the number of patients who need to receive a treatment for one additional patient to benefit compared to control. It is calculated as 1 / absolute risk reduction. An NNT of 1 would mean every patient benefits (ideal); NNT of 10 means 10 must be treated for 1 to benefit. NNT provides an intuitive measure of practical clinical impact. In supplement research, NNTs tend to be higher than for pharmaceutical drugs, reflecting more modest effect sizes. NNT should always be considered alongside potential harms (number needed to harm, NNH) for risk-benefit assessment.