10/07/2025
Our antioxidant defenses decline over time. The "free radical theory of graying" suggests that, as we age, the free radicals naturally produced during pigment production aren’t cleaned up as effectively. Eventually, this damages our pigment-producing cells, leading to gray hair.
Graying is thought to be mainly genetic. Up to 90% of people with premature graying have a family history of it.
If the rate of graying is caused by oxidative damage, though, what role might antioxidants play?
People with premature graying tend to have higher circulating markers of oxidative damage and lower levels of antioxidants in their blood. The link between smoking and premature graying supports the possibility that free radicals may speed up the graying process. Interestingly, alcohol consumption, which also causes oxidative stress, is not significantly associated with premature graying.
For those eating a plant-based diet to boost their antioxidant intake, vitamin B12 is the Achilles’ heel. Without supplements or fortified foods, B12 deficiency is a real risk.
Vitamin B12 deficiency is one of the rare reversible causes of hair graying. Thankfully, hair can repigment after B12 levels are restored.
Hypothyroidism is another reversible cause of premature graying. Hair can return to its natural color once properly treated.
Watch the video “Why Does Hair Turn Gray?” at see.nf/3XUlqS8 and “Reversible Causes of Prematurely Graying Hair” at https://bit.ly/3ONF7ab to learn more.
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