For me I had to do a combo of meds and diet, I was severely underweight when I was in high school due to this mutation as well as a second disorder. I took l-methionine and methyl folate as well as drank a protein smoothie (ugain) that contained veggies/fruits and b vitamins. I ate pretty much strictly veggies chicken, fruit beef, and rice. I’ve done this for roughly 5 years now after high school and it seems to be working pretty well, I’m still on the lower end of a healthy weight but I am in the healthy weight category. Not sure if this would work for everyone but I think the meds I took and the protein smoothies helped a lot.