How thinking too much could give you gray hair

There is an old proverb "If you think too much, your hair will go gray at young age". Gray hairs are a symptom of aging, but some young people already have it. Though this phenomenon is commonly related to genetic problem, it sometimes has relevance to diseases such as hyperthyroidism, hypothyroidism, diabetes and so on. According to this, the saying is correct that psychological stress can disrupt blood flow and it can cause abnormal hormone production to arouse a decrease in melanin pigment.

Before reading this article, I believed that the old saying was just a myth. I thought of my parents' gray hair after reading it. My parents' hairs turned gray earlier than other people, and I think it was due to trouble that I and my sister made. The change of hair color is not likely to be reversible, so I will try my best to be nice to my parents, and I also control stress well to avoid gray hairs.

Lee Dong-youn, How thinking too much could give you gray hair. The Korea Herald. April 11. Web.
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