The speed at which a man's facial hair grows is generally determined by genetics, with most men beginning to grow facial hair during puberty and continuing to grow it thicker and fuller as they age. Still, it is thought that getting plenty of sleep, exercising regularly and eating a diet high in protein and certain vitamins may help facial hair grow more quickly.
Vitamins A, B-1, B-6, B-12, C and D each play an essential role in hair growth, which is why eating foods that contain high levels of these vitamins or taking supplements may help increase the rate of facial hair growth. Keeping the face clean and well moisturized also encourages facial hair growth.
Protein is one of the major building blocks of hair, which is why it is also essential for rapid growth. On the other hand, sugary foods should be avoided as they can make the hair brittle and easily broken. Testosterone levels also affect the rate of hair growth, which is why exercise is so important, as it is one of the best methods for increasing testosterone.
One common myth is that shaving will make facial hair grow faster, but there is no evidence to support this claim.