L-Methionine
L-methionine is an essential sulfur-containing amino acid that has to come from food. The body uses it to make proteins, cysteine and SAMe.
What happens to homocysteine?
A German crossover trial in 20 women tested 500 mg three times daily for four weeks. Blood homocysteine rose by about 2 µmol/L despite adequate vitamin status. This is a biochemical finding; the trial did not show that supplementation caused heart attacks. 1
What did a tolerance study find?
Fifteen healthy older adults received increasing doses for four weeks each. Homocysteine increased at the highest dose, 91 mg/kg daily. The authors estimated a no-observed-adverse-effect level of 46.3 mg/kg daily. A small, short study cannot establish a universal long-term upper limit. 2
Effects by health goal
Open an effect to see the studies behind its rating. Bars show the size of the effect; the letter grades the evidence.
Immune Support1 effect
No study is linked to this rating.
Bone & Joint1 effect
No study is linked to this rating.
Organ Function1 effect
No study is linked to this rating.
Hair & Skin2 effects
No study is linked to this rating.
No study is linked to this rating.
Weight Management1 effect
No study is linked to this rating.
Longevity1 effect
No study is linked to this rating.