Thinning hair isn't just a problem for men—like many women, Kristin is experiencing hair loss. "I want to know how to slow it down, how to prevent it, and what are my options to try to get the thickness back," she says.

Dr. Northrup says that Kristin's thinning hair may be a result of a hormonal imbalance. "You can get it back by eating a low-glycemic diet, making sure that you are on supplements," she says.

According to Dr. Northrup, glycemic foods can cause dramatic changes in the body. "One of the things that often happens in mid-life to people is if they have a lot of stress hormones in their system and they're eating a high-glycemic diet, and the high insulin is in their blood from the high sugar ... that actually changes the way hormones are metabolized. So you actually begin to shoot your estrogen and progesterone into androgen-like substances that produce male pattern baldness in women. Have you seen this—where [women] start to get a beard and they get thinning of the hair at the temples and so on?"

Other than a low-glycemic diet, Dr. Northrup has one other recommendation for thinning hair. "Acupuncture can be very, very helpful for it," she says.