Psst… Your hair’s trying to tell you something.

From premature graying to male pattern baldness, from thinning tresses to red locks, the state of your mane holds clues about your current and future health. Read on to learn how to decode them.

Thinning hair in women

Estrogen promotes the growth of thick, lustrous hair. That’s why women’s hair often looks fantastic during pregnancy. But when estrogen drops after childbirth or during menopause or the years leading up to it, a woman’s hair often thins.

The hair-health connection: As estrogen falls during perimenopause, the balance between a woman’s natural levels of “female” and “male” hormones shifts. Androgens (so-called “male’ hormones, though both men and women have them) become more influential, causing hair loss for some women. But androgens can also fuel the growth of hair in places like a woman’s upper lip, chin and cheeks, according to the North American Menopause Society.

Related: What’s Lurking in Your Family Health History?

Male pattern baldness

If you’re in your mid-40s and have male pattern baldness — a combination of moderate hair loss from the crown of the head plus a receding hairline in front — watch out: You have a 40 percent higher risk for aggressive prostate cancer later in life than men with a fuller head of hair, according to a 2014 study from the National Cancer Institute. The study involved 39,700 men, age 55 to 74, who were asked how much hair they had at age 45 and were monitored for prostate cancer.

The hair-health connection: Men with male pattern baldness often have higher levels of male sex hormones (androgens) and more androgen receptors, which may the risk for aggressive prostate cancer, the researchers say. 

Related: 11 Health Symptoms Men Should Never Ignore

Top-of-the-head baldness

Baldness also increased risk for heart disease by 30 to 40 percent compared to men with plenty of hair, University of Tokyo researchers found. Men with severe “vertex baldness,” as this top-of-the-head baldness pattern is called, had a 48 percent higher risk, while those with minimal hair loss on top had an 18 percent higher risk. Women luck out here: Females with thinning hair weren’t at greater risk for heart disease.

The hair-health connection: The researchers note that other studies found links between male baldness and high blood pressure and higher-than-normal levels of insulin (the hormone that tells cells to absorb blood sugar). They advise men with vertex baldness to keep an eye on blood pressure, cholesterol and blood sugar levels.

Redheads

If you have naturally fiery hair, anesthesia may not work as well on you. The same gene variant that produces red or auburn tresses may increase susceptibility to pain while reducing the effectiveness of anesthetics used by dentists, studies show. As a result, carrot tops may be more anxious about dental procedures. They were twice as likely to avoid the dentist as people with blonde, brown and black hair in a 2009 Cleveland Clinic study.

The hair-health connection: University of Louisville researchers report redheads need about 20 percent more anesthesia and are more resistant to lidocaine than those with other hair hues. If you’re skipping dental exams because you’re worried about pain, talk to your dentist. 

Related: 10 Health Symptoms Women Should Never Ignore

Fair-haired folks

Redheads, blondes and people with light-brown hair are at higher risk for skin cancer. A mutation in the melanocortin-1 (MC1R) gene receptor is responsible for red hair, light skin, and a higher risk for melanoma, the deadliest form of skin cancer. Melanoma starts in pigment-producing skin cells called melanocytes, often due to damage caused by the sun’s ultraviolet rays.

The hair-health connection: In people with this MC1R variation, sun exposure activates a pathway inside cells that promotes cancer, report researchers from Harvard Medical School. Meanwhile, Australia’s Queensland Institute of Medical Research found melanoma risk was tripled for redheads, doubled for blondes and 46 percent higher for those with light brown hair compared with the risk in people with dark hair. Lower your risk by wearing sunscreen, a broad-brimmed hat, long-sleeved shirts and long pants and avoiding the sun between 10 a.m. and 4 p.m.

Premature gray

Stressed-out parents often blame their kids for their gray hair (mostly jokingly). But the early onset of gray hair can be a symptom of a sluggish thyroid gland, say New Jersey Medical School dermatologists.

The hair-health connection: German researchers reported in a 2013 study that changes in thyroid hormones affect hair follicles, leaving hair dry, brittle and dull if thyroid levels drop. Talk with your doctor if you have signs of a potential thyroid problem such as fatigue, increased sensitivity to cold, joint or muscle pain, unexplained weight gain or weakness, the National Institutes of Health (NIH) suggests. 

Related: Could You Have Polycystic Ovary Syndrome?

Lack of hair on toes, legs

Though shaving-weary women may welcome less hair on their legs, little or no hair on your toes or legs could signal a circulation problem. Peripheral arterial disease (PAD) squeezes or even blocks blood flow in legs and arms, thanks to a build-up of gunky plaque in artery walls. Smoking, diabetes, high blood pressure, high cholesterol and simply being older than 50 all raise your risk. Symptoms include leg pain, slow-to-heal sores on your legs or feet, pale or bluish skin and poor hair and nail growth, according to NIH.

The hair-health connection: Reduced blood flow robs hair follicles of oxygen and fuel needed to keep growing hair. If you have any signs of PAD, talk with your doctor. Healthy lifestyle changes and medications for high blood pressure, cholesterol and diabetes, if needed, can reduce symptoms and help you stay active.

Sari Harrar is an award-winning health, medicine and science journalist whose work appears in Dr. Oz The Good Life magazine, Good Housekeeping, O--Oprah Magazine, Organic Gardening and other publications.