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Losing pigmentation in your color-producing hair cells is normal with aging. But when your hair starts to gray earlier than you might expect, it could be related to your thyroid. The thyroid is responsible for regulating your metabolism, so when your thyroid is not working correctly, it can affect every cell in your system - including your hair. Ahead, why hypothyroidism and gray hair often go hand in hand and what you can do to get your color back.
Hypothyroidism, also known as an underactive thyroid, is when your thyroid gland does not produce enough thyroid hormone to maintain a healthy metabolic rate.
The thyroid is a butterfly-shaped gland situated just below the Adam's apple of the neck. This tiny gland is part of the endocrine system because its job is to make and secrete hormones. The thyroid produces thyroxine, or T4, which is then converted to triiodothyronine, or T3, to be used by your cells.
Thyroid hormones tell cells what to do and how fast to do it. So, when you do not make enough thyroid hormone, it can slow down all your cells and systems. Because every cell relies on thyroid hormone, there are numerous symptoms associated with hypothyroidism.
Common signs and symptoms of hypothyroidism:
- Fatigue and lethargy
- Cold intolerance
- Weight gain
- Muscle and joint pain
- Dry skin and brittle nails
- Hair thinning and changes in texture
- Slowed heart rate
- Irregular menstrual bleeding
Because every cell relies on thyroid hormone to regulate its functions, hair cells are equally affected by low circulating thyroid hormone. To understand how an imbalance in thyroid hormones can affect hair health, it helps to understand the hair growth cycle.
The hair growth cycle has four main phases: anagen, catagen, telogen, and exogen.
Anagen is the growth phase, where a new shaft grows from the follicle. This phase generally lasts 4-7 years, where the duration of growth is primarily determined by genetics. People who can grow long hair typically have longer anagen phases. Health problems can also interfere with this cycle.
Catagen is a short, transitional resting phase lasting about 14 days, where the hair shaft stops growing and begins to transition into the final phase.
Telogen, the last phase, is where the follicle no longer nourishes the shaft and stops growing. Lasting around three months, this phase ends with the hair shedding.
Fortunately, every hair does not go through each phase simultaneously. Otherwise, we would have long periods where we do not have hair.
Most studies show that an imbalance in thyroid hormone can throw off the hair growth cycle. As a result, one of the most common hair problems in thyroid conditions is hair loss. This symptom is likely the result of hair follicles having a decreased metabolism, causing it to take longer to grow new hair after it sheds. And when the hair does grow back, it is often brittle, thin, and lacking in color.
In a study examining scalp hair follicles, T4 was found to up-regulate the production of hair matrix keratinocytes - the cells that make hair strands. Likewise, apoptosis (or cellular death) is down-regulated by T3 and T4. T4 lengthens the anagen phase by suppressing TGF-β2, a receptor that suppresses cellular growth. Further, T3 and T4 also stimulate the production of intrafollicular melanin synthesis, which gives you hair color.
Intriguingly, people with hyperthyroidism also have similar hair struggles, where the hair is thin and lacking in color. Hyperthyroidism is a condition where there is too much thyroid hormone in the circulation. Thus, too little or too much thyroid hormone can affect hair color, volume, and texture.
Having hypothyroidism does not mean you have to live with lackluster hair. However, given how long it takes hair to grow under normal circumstances, it can take time to better your hair health and appearance.
An essential part of reversing hair symptoms associated with hypothyroidism is restoring your thyroid hormone levels to normal. For most people, this involves taking thyroid hormone medication to increase the amount of T4 circulating in your bloodstream. Some people benefit from combining T4 and T3, or even T3 alone.
You will need thyroid testing to determine what type of medication and dose is best to treat your underactive thyroid.
Next, giving your hair (and body) the proper nutrients to support healthy hair growth is important. Hair follicles need plenty of iron, protein, vitamins, and minerals for optimal growth. The best way to get these nutrients is through your diet. Still, some people with nutrient absorption issues (which often happens to people with hypothyroidism) may benefit from taking additional supplements. Fortunately, many nutrients your hair needs (like selenium and vitamin D) are also crucial for thyroid health. As with any supplementation, it is essential to consult your doctor before adding anything new to your medication regimen.
Healthy hair habits are also essential. For example, it may help to use a hydrating shampoo and conditioner designed for people with dry hair. Spacing out how often you wash and style your hair with hot styling tools can also help. Additionally, if you dye gray hair, it may help to take a break from coloring to decrease any inflammation surrounding the hair follicles.
Lastly, our hair is just as prone to the adverse effects of stress as our skin and other organ systems. The benefits of getting plenty of rest, reducing stress, and taking care of yourself mentally and physically can evolve into a healthy head of hair.
A note from Paloma Health
The first step toward treating a thyroid condition is getting accurate, comprehensive thyroid testing that looks at TSH, free T4, free T3, and TPO antibodies. Check your thyroid levels with a Paloma at-home thyroid test kit that is simple, accurate, and complete. Our thyroid doctors can follow up with you on a tailored plan of care to treat everything hypothyroid-related, from your fatigue to your hair.