The Connection Between Weight Loss and Hair Loss

The American Academy of Dermatology (AAD) reports that there are a few potential reasons for hair loss. But first, it stresses that there is a difference between hair shedding and hair loss. While shedding some hair is normal—everyone loses 50 to 100 hairs each day—hair loss occurs when you see unusual thinning or patches of hair loss on your head.

If you are experiencing actual hair loss, what could be the cause? Weight loss hair loss is one possibility. So too are hormone changes, stress, medications, and more. Does this mean that you have to deal with hair loss if one of these reasons exist? Not necessarily. Several treatment options, depending on the type of hair loss and cause.

Types of Hair Loss

There are several types of hair loss. However, two of the most common are androgenetic alopecia and telogen effluvium.

Androgenetic alopecia is a type of hair loss that is largely genetic and affects up to one half of males and females both. People with androgenetic alopecia have higher levels of hormones called androgens in their hair follicles. These androgens not only shorten the hair growth cycle but they also cause shorter and thinner hair strands that don't immediately start to regrow once they are shed.

Telogen effluvium is another type of hair loss and is more of an excessive shedding. Although its exact occurrence rate isn't known, telogen effluvium is thought to be quite common with many adults experiencing this condition at some point in their lives. Sometimes it is acute, occurring for a short period of time, and in other instances it is chronic, or longer-lasting.

Reasons for Hair Loss

The first step to deciding how to best handle your specific type of hair loss is to identify its cause. And there are many potential reasons for losing hair.

Heredity

You've probably heard of male-pattern baldness but did you know that women can also experience this genetic condition? Female pattern baldness, which falls under the androgenetic alopecia type of hair loss, can run in families and looks slightly different than male-pattern baldness.

Women usually experience this hair loss on the top and crown of the scalp and often describe seeing a widening part. You're more likely to experience female-pattern baldness if you have a family history of the condition.

Hormone Changes

Changes in your hormone levels can cause hair thinning. A change in your androgen levels may cause the hair on your head to thin and the hair on your face to feel more coarse.

You might notice changes in both your hormones and your hair during menopause. Approximately two-thirds of women experience some postmenopausal hair loss.

Nutritional Deficiency

If you are lacking in certain nutrients, you may experience hair loss. Nutritional deficiencies have been linked to both androgenic alopecia and telogen effluvium, with lower levels of some vitamins and minerals leading to the loss of more hair.

Low iron is one to consider. If you are a vegetarian, have heavier than normal periods, or have a history of anemia, you may experience hair loss from iron deficiency. Some women take iron supplements to reverse the condition but there is no evidence to support their effectiveness for hair loss.

Low levels of zinc, niacin, selenium, vitamin D, and several other nutrients are additional diet-related considerations that might be explored if you are experiencing hair loss. Low protein intake has also been found as a potential cause of hair loss and very low-calorie diets, in general, don't provide enough nutrition to allow your body—including your hair follicles—to function normally.

Physical or Emotional Stress

It is not unusual to experience hair loss when you are also experiencing elevated stress or anxiety levels. The increase in stress triggers the release of hormones (like cortisol) that increase inflammation and can cause hair growth to slow or stop, also causing some hair to fall out.

Some people eat less when stressed or emotionally upset. If food intake becomes too low, this can further contribute to hair loss, also potentially increasing the risk of becoming deficient in the vitamins and minerals needed to support healthy hair growth and function.

Thyroid Disease

Thyroid dysfunction is another possible cause of hair loss. Any thyroid patient may experience hair loss, including those with Hashimoto's disease and Basedow's disease as up to 28% of people with these conditions experience hair loss.

Your physician can run tests to see if your thyroid gland is functioning properly. In fact, some health professionals recommend that any patient with alopecia (hair loss) be screened for thyroid issues to determine if this is the possible cause.

Medications

The taking of some medications has been linked to hair loss. Among these medications are:

• Allopurinol, sometimes prescribed for people with gout or kidney stones
• Bromocriptine, which can be used to treat Parkinson's disease, tumors, or type 2 diabetes
• Cyclophosphamide, a chemotherapy drug
• Doxorubicin, another chemotherapy drug
• Levodopa, a medication-based treatment for Parkinson's disease
• Nitrosoureas, sometimes used for cancer or brain tumor treatment
• Tamoxifen, used to treat breast cancer

Medication-related hair loss typically resolves itself within one to three months after no longer taking the drug.

Weight Loss

Weight loss, alone, isn't always listed as a potential hair loss cause. But that doesn't mean you won't experience hair loss when you lose weight.

Dieting can be stressful and exhausting. It can also lead to nutritional deficiencies that result in hair loss. Additionally, many women experience weight gain as they age or during menopause and may go on a diet as a result. This combination of factors may cause your hair to thin.​

Treatments

If you notice unusual patterns of hair loss, see your doctor. Your healthcare provider can tell you if a related medical condition can be the potential cause of changes to your hair.

You may get referred to a dermatologist who can run additional tests to find out why you might be losing hair and what can be done about it. They may also refer you to a registered dietitian or behavioral health specialist if nutrition problems or stress is the cause.

There are medications that can improve thinning hair. They include:

• Minoxidil: You've probably seen products like Rogaine (minoxidil) advertised on television or in magazines. This medication is widely used and has been shown to be effective in clinical trials. The over-the-counter medication is available in pharmacies.
• Spironolactone: This prescription medication has not been approved by the FDA to help women with thinning hair but it is a common treatment for hair loss in women because it has been shown to be effective, according to the American Academy of Dermatology.

There are a few other medications that can be used off-label to treat hair loss during weight loss. Your dermatologist can determine if one of them is right for you. Lasers and hair transplantation are also methods used by some to treat hair loss, but these treatments are not appropriate for everyone and don't always work.

A Word From Verywell

While hair loss can be upsetting, depending on the cause, it may be short-lived or even reversible. Your doctor can help you determine what is leading to your hair loss while also providing treatment options that are likely to provide the best hair restoration results.