Androgens, such as testosterone (T), dihydrotestosterone (DHT), and their prohormones dehydroepiandrosterone sulfate (DHEAS) and androstenedione (A) are the key factors in the growth of terminal hair.
The female sex hormone oestrogen makes body hair fine and soft. Androgens are male sex hormones, including testosterone, which are responsible for masculine characteristics such as facial hair and coarse body hair. A woman's ovaries and adrenal glands naturally make a small amount of androgens.
DHT: The hormone behind hair loss
Dihydrotestosterone (DHT) is made from testosterone by an enzyme called 5-alpha reductase. It can also be made from DHEA, a hormone more common in women.
Lifestyle changes, such as a healthier diet, exercise, and stress reduction will also help you get your hormone levels back on track. Once equilibrium is restored to your hormones, hair loss associated with your hormone issue should slow or cease, and in many cases, hair that was loss may be replaced by new growth.
Estrogen and Progesterone
These hormones also help with hair growth. Estrogen and progesterone can help keep your hair in the growing (anagen) phase. Therefore, these hormones can help your hair stay on your head longer and may even help your hair grow faster.
When the levels of estrogen and progesterone drop, hair grows more slowly and becomes much thinner. A decrease in these hormones also triggers an increase in the production of androgens, or a group of male hormones. Androgens shrink hair follicles, resulting in hair loss on the head.
Elevated estrogen levels are often associated with hair growth during pregnancy. However, in cases of estrogen dominance, too much estrogen can lead to hair loss.
As with male pattern baldness, female pattern baldness comes from hormone imbalances, specifically dihydrotestosterone imbalances, or DHT. This hormone is similar in structure to testosterone, but it is significantly more potent [3]. DHT can attach to receptors on the hair follicles, causing the follicles to shrink.
Estrogen and progesterone levels fall, meaning that the effects of the androgens, male hormones, are increased. During and after menopause, hair might become finer (thinner) because hair follicles shrink. Hair grows more slowly and falls out more easily in these cases.
Dihydrotestosterone (DHT) is an androgen. An androgen is a sex hormone that contributes to the development of what are thought of as “male” sex characteristics, such as body hair. But it can also make you lose your hair faster and earlier.
Biotin. Biotin, also known as vitamin B7, is a complex B vitamin that is often touted for having hair growth benefits. And some of that hype may actually be worth it. Biotin has functions in “creating red blood cells, which carry oxygen and nutrients to the scalp and hair follicles,” says Dr. Green.
As these hormone levels drop, hair may begin to grow more slowly and become thinner. Over time, the decrease in estrogen and progesterone causes an increase in the activity of male hormones (called androgens) that the body makes. Androgens cause the hair follicles on the head to shrink, which leads to hair loss.
In addition to keeping your bones strong, estrogen and progesterone keep your hair healthy. A decrease in these hormones causes an increase in androgen production which causes hair follicles to shrink and contribute to hair loss.
Estrogen Excess
Just like excess testosterone and excess DHT can cause hair troubles, so can too much estrogen. For some women, excess estrogen may trigger hair loss because of a gene variant that affects the functioning of an enzyme (aromatase) that processes estrogen.
Lower estrogen and progesterone levels: Estrogen and progesterone stimulate hair growth, which is why pregnant women—who are producing extra levels of these hormones—tend to experience thickening hair during their pregnancy.
Women's hormone levels decline and then sharply drop off during menopause. As a result, this can throw off the balance of the body's chemistry, and potentially lead to issues with DHT levels. Some women experience increased sensitivity to testosterone and DHT during menopause, which exacerbates hair loss and thinning.
A Fred Hutchinson Cancer Research Center study involving postmenopausal, overweight, and obese women who took 2,000 IUs of vitamin D daily for a year found that those whose vitamin D blood levels increased the most had the greatest reductions in blood estrogens, which are a known risk factor for breast cancer.
It depends on your situation. Not all women need, want or are candidates for estrogen therapy. Estrogen can reduce menopausal symptoms like hot flashes, night sweats and vaginal dryness. If you have a uterus, you'll likely need to take progesterone along with the estrogen.
How much B12 should I take daily for hair growth? The lowest amount recommended that should be traceable in your body is 2.4 mcg. While you are looking for a difference in your hair growth you can increase this dosage to 3 mcg and beyond.