The dosage of NMN may vary from person to person. Some people may feel high energy levels after 250mg of NMN intake while others may need at least 500mg. A study in mice showed that 100 mg/kg per day mitigated most age-related physiological decline. Based on that dosage, for an average adult weighing 62 kg (about 137 pounds), an optimal dosage would be about 500 mg per day. This calculation is based on dividing the human dosage by a factor of 12.3 to match the rodent “volume of distribution.” In the same manner, larger adults weighing 90 kg should take about 750 mg per day.