Phosphatidyl Serine: Safety Assessment

Scientists demonstrated in several studies that a daily intake of 300 mg phosphatidyl serine (PS) from bovine cortex was tolerated by patients. In addition, a clinical trial evaluated human tolerance to phosphatidyl serine from soy.

The researchers described an intake of 200 mg of soy phosphatidyl serine three times daily as safe in elderly subjects. Further studies showed that no side effects were associated with an intake of 300 mg phosphatidyl serine daily for 15 weeks.

The Norwegian Scientific Committee for Food Safety (VKM) evaluated the safety of intake of L-serine, an acetylated derivative of N-acetyl-serine and phosphatidyl-serine, based on several studies. Side effects, such as mild histopathological changes, were evident in one animal study at doses 3,400 mg/kg body weight/day. This value corresponds to 1,666 mg/kg body weight PS.Taking this into account, an intake value (No Observed Adverse Effect Level, NOAEL) could be determined with which no side effects were observed from the intake. This amounts to 1,029 mg/kg body weight/day PS.

The VKM concluded that adverse effects are very unlikely at L-serine intakes of up to 1,750 mg daily in adults (≥ 18 years) and up to 1,500 mg in young adults (14-18 years).