What is Homocysteine: How to Support Balanced Levels Seeking Health Oxidized glutathione hi res stock photography and images Alamy Homocysteine and methionine are key amino acids with a vital connection to glutathione one of your body's most important substances! Methionine is abundant in many foods, so protein isn't the culprit, 87 studies. 9,000+ children. and most parents have never heard this conversation. A meta analysis of 87 studies involving over 9,000 children found consistently lower glutathione levels and higher oxidative stress in children