Eat a balanced amount of protein every day. Protein is essential for healthy hair growth. Just make sure you eat the right amount.
Hair is largely composed of keratin, a protein made up of amino acids. To grow new hair, your body must produce more amino acids, which it can only do from consuming protein.
Maintain good general health and avoid stress. Eat well, exercise regularly, and get enough sleep to reduce general physical stress levels. Intense physical or emotional stress can cause hair growth to slow or shut down completely. In severe cases, stress can cause hair loss.
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There is a joke. A bald man wanted to grow hair very fast. Some one administered him an oil. He applied it on the head overnight and slept. When he got up in the morning, his head was full of hair and he was very happy to look himself before the mirror. But one thing shocked him. When he saw both his palms, lot of hair had grown on his palms. He started crying. The lesson is that, nothing can go against nature. If one has to become bald, he has to accept it. Nothing can make hair grow artificially. People exploit the expectations and fool the people. Don't fall a prey for all these things.