Many things “may vary depending on an individual’s age,” he said...
well, yeah.
I thought the Alphabet People had gone far enough with men posing in women's swimsuits, but animal models is even more hilarious. :-P
if your genome carries one of the (I think the number is 5) MTHFR gene mutations, your body cannot process folic acid and therefore cannot process vitamin B. Almost everybody has at least one genetic mutation. I have three. The more folic acid you add to your diet, and the more processed food you consume, the more toxic you become because the body cannot process it out. And they add it to wheat, to cereals, to just about every processed food. But it also means that no matter how much extra vitamin B you are taking, it’s not being used by the body and you just pee it out. This results in a deficit of vitamin B and can result in numerous problems, chiefly anxiety disorders, sleep disorders, depression, panic attacks and other neurological disorders.
You should test for MTHFR mutations and then take a methyl-folate with your B so the body can absorb it. I was a lifelong nail chewer; I used to bite my nails and cuticles until they bled. A couple of weeks on methyl-folate B Vitamins and that habit completely disappeared, as did my anxiety attacks.
I had no idea about the metabolism part, but it totally makes sense.