Methionine is metabolised to homocysteine and raised plasma homocysteine is associated with birth defects, pre-eclampsia, spontaneous abortion and placental abruption.
15, 16
Schizophrenic patients
Schizophrenic patients given 10–20 g methionine daily developed functional psychoses.
17
Patients with pre-existing cancer
Animal studies have shown that restriction of methionine intake blocks division and metastasis of tumour cells.