Interestingly, dietary supplementation with high levels of methionine has been shown to attenuate arthritis severity in arthritic rats, and also to increase levels of serum Insulin-like Growth Factor-1 (IGF-I) [71], and to this point, IGF-I was previously found to be significantly lower in female patients with RA than in controls [72]. The gene discussed is IGF1; the disease is arthritic joint disease.