Taking a daily fish oil supplement may help stave off(避ける、免れる)mental illness in those with a high risk of developing psychosis(精神病). For a recent study, researchers selected 81 people who had a strong family history of mental disorders like schizophrenia(統合失調症)or who were already showing mild symptoms of such a condition and gave them either fish oil supplements or placebos for 12 weeks. At one year, just 5 percent of those taking the supplements had developed a psychotic disorder, compared to 28 percent of those in the placebo group. These findings suggest that fish oil is as effective as antipsychotic drugs in delaying or preventing the onset of psychotic disorders.