It is unlucky for an old man to have black hair.

1, turning white hair to black in the elderly is probably a disease signal. Sometimes the elderly will occasionally rejuvenate. Many people think that this is a good sign of health and longevity, but it is not. Medical experts pointed out that these phenomena are often signals of disease occurrence and should be paid enough attention. Vision improvement, early signs of cataract, vision improvement. Some old people have suddenly improved their eyesight after wearing reading glasses for a period of time. This abnormal phenomenon is an early sign of cataract.

2. Some elderly people's hair suddenly turns black and white, especially with delicate skin and sexual hyperfunction. Many old friends are very excited and think that they are getting younger and younger, but in fact, this is probably an early signal of serious diseases such as pituitary adenoma and adrenal cell carcinoma.

3. Some old people's hair suddenly turns black, especially accompanied by skin tenderness and sexual hyperfunction, which is probably caused by pituitary abnormalities and lesions.

4. It may also be due to dietary changes such as eating black sesame paste, some basic cells of hair are overnourished, or the surrounding water quality and air quality have changed, and nutrient metabolism, trace element metabolism and vitamin metabolism are in an abnormal balance state. This is a normal physiological change.

5. It is necessary to observe the situation in detail. Generally speaking, when people get old, their hair will gradually turn white, which is a kind of physiological aging. It should be noted that if the white hair turns black again, especially with "rejuvenation" such as delicate skin and hypersexuality, it is likely to be related to serious diseases such as pituitary adenoma and adrenal cell carcinoma. It is recommended to go to the hospital for a detailed examination. If it is only blackening without other diseases, it may be a sign that the elderly are in a good mood, balanced nutrition and healthy.