Hello and welcome to the Nutrition Diva podcast. I'm your host Monica Reinegel, and I have

a question about digestive enzymes from Jennifer. But first a question from Melissa who wants

to know, are there supplements that can prevent graying hair? I have seen some for sale

on cosmetics websites, and I'm wondering whether there's any science behind them.

Yes, and no. I checked out a half a dozen or so of these supplements or serums that claim to

delay the graying of hair. And many of them cited a long list of scientific studies to support

their claims. But a closer look at the science left me unconvinced. Most of these citations had

to do with premature graying. So people who start to go gray in their 20s and for whom early graying

doesn't run in the family, because graying is a highly heritable trait. Some of these cases of

premature graying were eventually linked to deficiencies of certain nutrients, such as copper

or B12. However, for people who are starting to go gray in their 40s or 50s, which is when this

typically happens, nutrient deficiency is a much less likely explanation. And accordingly,

supplementing with more of those nutrients isn't likely to do much for you.

Almost all humans will eventually end up with gray or white hair, unless, of course, they end up

with no hair. And this is because the production of melanin, that's the pigment that gives hair

its color, tends to decrease with age. Some of these formulas claim to provide nutrients that are

essential for the biosynthesis of melanin, which sounds pretty scientific, but there is a logical

fallacy here. Imagine a factory full of aging workers who can't build widgets as quickly as they

did when they were younger. Well, bringing more and more raw materials into the factory isn't going

to make your elderly workers move any faster. And similarly, loading the body up with melanin

precursors won't necessarily result in higher melanin production. Once hair has turned gray or white,

there's really nothing you can do to restore its former color, sort of dying it. So the only

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