You notice more hair on the brush. A little more scalp showing than last year. Easy to chalk it up to getting older, but that may not be the whole story.
Yes, age-related pattern baldness is common. It affects up to 80% of men and 50% of women over a lifetime. But several medical conditions can also cause hair loss, and many of them become more likely as we get older. Knowing the difference matters, not just for your hair, but for your overall health.
Gretchen Dueñas-Tanbonliong, MS, MPH, RDN, MCHES, Associate Director of Health and Wellness at the National Council on Aging, put it plainly: “There are several illnesses that commonly cause hair loss. And some of them go hand-in-hand with getting older. Meaning: it sometimes can be hard to tell whether our hair loss is because of age or something else.”
Your Thyroid Could Be the Culprit
About 20 million Americans have a thyroid disorder, and the odds of developing one go up as we age, especially for women 60 and older.
Your thyroid gland runs your metabolism, the process your body uses to turn food and oxygen into energy. A healthy thyroid produces three hormones (T3, T4, and calcitonin) that keep things running smoothly.
When the thyroid is underactive (hypothyroidism), it doesn’t make enough of those hormones. When it’s overactive (hyperthyroidism), it makes too many. Either way, the hair growth cycle gets thrown off. In hypothyroidism, new hair grows much more slowly than normal while shedding continues at the usual pace. In hyperthyroidism, new hair grows normally but shedding speeds up. Both result in diffuse thinning across the scalp and sometimes the eyebrows, pubic region, and other areas of the body too.
Here is the part that should give you pause: an estimated 60% of people with thyroid disease don’t know they have it. Paying attention to hair changes could prompt a conversation with your doctor that uncovers something important.
Two common thyroid conditions, Graves’ Disease (a form of hyperthyroidism) and Hashimoto’s thyroiditis (a form of hypothyroidism), are also autoimmune conditions, which brings us to the next piece of the puzzle.
Autoimmune Conditions and Hair Loss
About 15 million Americans live with one or more autoimmune conditions. With autoimmunity, the body’s immune system mistakenly attacks its own healthy cells and tissues instead of outside threats like bacteria and viruses. Increasing age appears to be a possible risk factor, though researchers are still working out exactly why.
Several autoimmune conditions are closely linked to hair loss:
- Alopecia areata — The immune system attacks the hair follicles directly, causing small round bald patches. In some people, hair loss is more widespread. It tends to happen suddenly. Hair often does grow back, but timing is unpredictable.
- Celiac disease — In celiac disease, gluten triggers an immune attack on tiny hair-like structures in the intestine called villi, which absorb nutrients from food. Vitamin D and B12 deficiencies, common in celiac, may be linked to hair loss. People with celiac are also more likely to develop alopecia areata.
- Lupus (systemic lupus erythematosus) — Lupus can affect the kidneys, heart, joints, and skin. It can cause rashes and sores on the scalp that damage follicles. Some medications used to treat lupus, including steroids and immune-suppressing drugs, can also trigger hair loss.
Diabetes Is Another Common Connection
More than 40 million Americans live with diabetes, including nearly 30% of people age 65 and older. Both Type 1 and Type 2 affect the pancreas, the organ that produces insulin to control blood sugar. Type 2 is most common in older adults, and the risk for developing it increases with age.
When blood sugar stays high over time (a condition called hyperglycemia), it can damage blood vessels and slow circulation throughout the body, including on the scalp. Hair follicles get less of the oxygen and nutrients they need. More hair falls out, and new hair grows back more slowly than normal. In some cases, people with diabetes also lose hair from their arms and legs.
The good news: managing diabetes with medication and lifestyle changes can help slow that hair loss or even reverse it.
Other Conditions and Causes Worth Knowing
A few more conditions and situations can lead to thinning hair, and several of them are especially relevant as we get older:
- Cancer treatments — It’s typically chemotherapy, radiation, and immune-suppressing drugs, not the cancer itself, that cause hair loss. The stress of a serious illness can also play a role.
- PCOS (polycystic ovary syndrome) — This condition, which mainly affects women, involves high levels of androgens (male hormones) that often cause pattern baldness. Up to 50% of people with PCOS also develop Type 2 diabetes.
- Psoriasis — This inflammatory skin condition causes cells to grow too fast, creating itchy, scaly patches. Psoriasis itself doesn’t make hair fall out, but scratching the scales on your scalp can. This type of hair loss is not permanent.
- Medications — Some prescription and over-the-counter drugs can cause hair loss, including medications for high blood pressure, high cholesterol, and heart arrhythmias like atrial fibrillation (A-fib).
- Stress — Big life changes like retirement and the loss of a loved one can trigger stress-related shedding. This is a known cause of hair loss and becomes more likely as we experience more of those significant moments.
- Surgery — Any major operation can trigger hair loss. Physical stress from the procedure, effects of anesthesia, and other factors can cause significant shedding, often several months after the surgery, and usually temporary.
- Poor nutrition — Hair follicles are sensitive to nutrient shortages. When the body is short on calories or key nutrients, it prioritizes vital organs. Hair gets pushed into a resting phase. This typically shows up as diffuse shedding about two to three months after the nutritional deficit began.
What You Can Do About It
The most important first step is simple: talk to your doctor. A health care provider can help figure out why your hair is thinning and that process might uncover a condition you didn’t even know you had.
If there is an underlying medical cause, treating it gives your hair a real chance to recover. Beyond that, some people do respond well to specific hair loss treatments, including prescription and over-the-counter options, supplements, and topical products. What works for one person may not work for another, and what’s right for women may differ from what’s right for men. Your doctor can help you sort through those options safely and realistically.
Hair loss can feel discouraging. But it can also be a signal worth paying attention to, one that leads you somewhere more important than you expected.