Spermidine recommended daily dosage
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Spermidine Supplementation Dosage: Human Safety and Efficacy
Human Clinical Trials: Safe Dosage Ranges
Recent clinical studies have tested a wide range of spermidine dosages in humans. A high-purity spermidine supplement at 40 mg per day for up to 28 days was found to be safe and well-tolerated in healthy older men, with no significant changes in clinical or laboratory parameters and no adverse events reported . Another study in older adults with subjective cognitive decline used a much lower dose—1.2 mg per day from a spermidine-rich wheat germ extract—for three months, also reporting excellent safety and tolerability, with no differences in health markers compared to placebo . Additionally, a year-long study in older adults with dementia used a daily dose of 3.3 mg, showing positive effects on memory performance and no safety concerns .
Pharmacokinetics and Short-Term Effects
A pharmacokinetic study administering 15 mg per day of spermidine for five days in healthy adults found that this dose did not increase spermidine levels in blood plasma or saliva, though it did increase levels of its metabolite, spermine. The study suggests that doses below 15 mg per day are unlikely to have short-term effects on spermidine levels in the body .
Lower Dosages in Combination Supplements
Some supplements combine spermidine with other compounds. For example, a blend containing 0.6 mg of spermidine per day, along with AM3 and hesperidin, was given for two months and showed improvements in immune function and biological age, with no reported safety issues .
Animal Toxicology and Safety Margins
Animal studies support the safety of spermidine at much higher doses. In a 90-day toxicity study in rats, no adverse effects were observed at doses up to 728 mg/kg body weight per day, indicating a wide safety margin for human supplementation . Preclinical studies in mice also found no toxicity or negative effects at doses used in supplementation studies .
Conclusion
Human studies have safely used spermidine doses ranging from 0.6 mg to 40 mg per day for periods from several weeks to a year, with no significant adverse effects reported 12346. The most commonly studied and recommended daily dosages in clinical trials are between 1.2 mg and 3.3 mg per day, especially for cognitive benefits in older adults 24. Higher doses, such as 40 mg per day, have also been shown to be safe for short-term use in healthy older men . Animal studies suggest an even wider safety margin . However, the optimal dosage for specific health outcomes may vary, and longer-term studies are needed to confirm efficacy and safety for different populations.
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