Identifying the underlying cause of hair thinning or loss is often a diagnosis of exclusion.
Thinning hair is a common complaint clinicians receive in the dermatology office. According to Medline Plus, it is estimated that 50 million men and 30 million women in the United States experience androgenetic alopecia alone.1 As we know, identifying the underlying cause of hair thinning or loss is often a diagnosis of exclusion and needs ample time with the patient. Reasons to rule out the cause include not only androgenetic alopecia but also telogen effluvium, anagen effluvium, alopecia areata, cicatricial alopecia, tinea capitus, hair shaft abnormalities, hypotrichosis as well as any underlying diseases. Hair loss is divided into scarring or non-scarring alopecias, and the workup, such as blood tests, a hair pull test, or light microscopy, can frustrate the patient, especially if all is normal. However, a biopsy may still give the clinician the answer. For the simplicity of this discussion, the focus will be on a common cause seen with medications and whether the recommendations for hair supplements and diet modifications can help support healthy hair growth once a diagnosis is made.
Commonly, certain medications can cause hair thinning or loss, and it is always essential to get a detailed history of current medications and supplements or other drugs the patient has taken in the past 6 months. As a general rule of thumb, if the drug causes a toxic insult to the hair follicle, then anagen effluvium will follow at least 2 weeks after introducing the agent. This type of hair loss, a fracture of the hair shaft, is seen with chemotherapy drugs, which patients are very familiar with due to the education involved when exposed to these drugs. This form of non-scarring alopecia commonly associated with chemotherapy provides reassurance that the hair will grow back once the offending agent is removed.2 Other anagen effluvium drugs include tamoxifen, allopurinol, levodopa, bromocriptine, and arthritis medications such as methotrexate, which the patient may not expect.
Other drugs that can induce hair loss, known as telogen effluvium, happen more gradually and are unknown to the patient, which includes retinoids, anti-depressants, long-term use high-dose NSAID use, or other anti-coagulants, along with beta-blockers and anti-thyroid medications. Though with some drugs, it is postulated to be a condition of telogen effluvium, the exact cause is unknown.3 Again, the hair will grow back once the offending drug is discontinued, however, that may not be an option for many patients because of their medical condition. One option may be to provide patients with products that have the potential to alleviate some of the thinning such as supplements and diet modifications. Often, the patient will seek supplementation to lessen the hair loss they are experiencing before making an appointment at a dermatology clinic.
Though diet can play a significant role in our overall health, sometimes the food we consume may not be enough to meet the demands of the body's optimal hair growth. It is known that nutritional deficiency can impact hair structure and growth and contribute to thinning. A common deficiency seen is low ferritin levels, resulting in low iron levels, a well-known cause of hair loss. Other hair-thinning nutritional deficiencies include zinc, niacin, fatty acids (omega 3 and 6), selenium, vitamins A, D, and E, folic acid, biotin, amino acids, proteins, and antioxidants.4 Consumption of eggs, seeds (flax, chia, sunflower), fish oils, berries, bone broth, and seaweed/kelp can help prevent hair loss. Avoidance of foods that can increase DHT, such as alcohol, processed foods, and sugars, should also be suggested. However, patients often want a more straightforward fix than adjusting their nutritional intake and turning to supplements, even though the appropriate food intake is recommended.
Hair supplements are a billion-dollar industry, and there is much controversy about whether they work. With information readily available on the internet and social media, and the marketing dollars spent to entice the consumer, they often turn to this advice before seeking professional help. In 2020, a retrospective study found that over 80% of women used hair supplementation, with 63% between 18 to 39 years old.5 According to the FDA, "Dietary supplements are intended to add to or supplement the diet and are different from conventional food."6 However, how many are proven to provide the benefits they promise? The goal is to provide the necessary nutrients for optimal health. As with anything, adverse events may occur by taking too much or interactions with current medications. As always, the consumer should discuss any supplementation with their provider. Many patients present at the clinic have already tried one or are seeking advice on which hair growth supplement they should consume. Despite limited data on efficacy and safety, some small studies point to positive outcomes.
An objective and subjective systemic review from January 2022 regarding the safety and efficacy of popular brands on the market "with the highest-quality evidence showed the potential benefit of Viviscal, Nourkrin, Nutrafol, Lamdapil, Pantogar, capsaicin and isoflavone, omegas 3 and 6 with antioxidants, apple nutraceutical, total glucosides of paeony and compound glycyrrhizin tablets, zinc, tocotrienol, and pumpkin seed oil."7 Another study found that a combination of arginine, silicon, magnesium, and biotin significantly increased hair thickness and even improved wrinkle depth on the skin without any adverse events.8 The studies noted that more research should focus on large randomized clinical trials and future studies are needed for justification, respectfully.
With many patients seeking to treat their hair loss before coming into the clinic, as dermatology clinicians, we see firsthand how hair loss "significantly has a psychological impact, resulting in symptoms of depression that impact the quality of life."8 It is imperative to work together with the patient and discuss all the risks and benefits of appropriate supplementation with the understanding that more research is needed and nothing can be promised to significantly impact the hair loss the patient is experiencing, especially if they are taking a medication that is contributing to the loss.