Read archived articles written by Palo Alto Medical Foundation doctors.

Puberty for Boys

From Holly M. Ginsberg, M.D., Pediatrician

Puberty is the period during which a body changes from a boy or girl into a young man or woman. Or, as a doctor might say, the body physically matures from childhood into adolescence.

Puberty begins at different ages. On average, boys begin puberty between ages 10 to 15 and the entire process can take up to four years. The body goes through many changes during puberty that are often unpleasant. Skin may get oilier and sweatier, which can lead to acne and body odor. Changing hormone levels cause our emotions to feel out of control at times. You may also have a lot of questions - what is happening to my body? Is this normal? Are other people going through the same thing? On a more positive note, the beginning of puberty also means you will grow taller.

A growth spurt is the first sign of puberty in boys. The later a growth spurt starts, the later it will continue. Thus, the smallest boy in the ninth grade can end up the tallest man in his graduating class. Along with this increase in height is a rapid gain in weight and shoulder width. Muscles get bigger without even lifting weights. Many boys and their families wonder if weight lifting and changes in diet will increase muscle mass. It is generally not recommended to do any heavy weight-lifting before 16 years of age. Instead, teenagers should focus on eating a healthy variety of foods and being physically active. Do not be tempted by supplements, powders or pills that promise leaner and stronger bodies; they are not well-regulated, and have the potential for being very dangerous.

Boys are often surprised by how their breasts change during puberty. A lot of boys will feel a swelling in the nipple area, and sometimes it is even a little painful. It is normal and only temporary. During puberty boys' vocal cords will get longer as they grow taller, which is why their voices crack and eventually deepen. Body hair and whiskers grow longer and darker. The thin, fine hairs that start growing in the pubic area (above the penis) will get darker and coarser like the rest of the body hair.

In the earliest stage of puberty, the testicles start to get larger. Next, the penis itself grows, and the scrotum becomes darker. Increasing levels of hormones cause erections, often for no reason at all. Boys also start producing sperm at this time. Sperm and whitish fluid called semen are released from the penis during ejaculation and "wet dreams", or nocturnal emissions, can occur when boys are asleep. This is normal and decreases with time. However, boys should see a doctor if they find any lumps on their testicles or any bulges (hernias) in their groin area.

As much growing as boys experience physically, they have even more "growing up" to do emotionally. Their minds and questions are becoming more complex, and they are less likely to ask their parents for help than before. Fortunately, doctors are sensitive to this - they were once kids themselves. Most will ask their teen patients if they want to be seen alone, for the sake of privacy. They are prepared for all kinds of questions boys may have, and they will try their best to help boys (and their parents) understand their bodies and their health.
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