Why does hair loss occur? Is there any way to prevent it?

為什麼會脫髮?有沒有方法可以預防脫髮?

Hair loss is a common problem that not only affects appearance but can also negatively impact a person's self-esteem. So, why does hair loss occur? And what can be done to prevent it?

Why does hair loss occur?

1. Genetic factors:
Genetics are one of the main causes of hair loss. Many studies have shown that hair loss may run in families. 1 A study published in Nature Genetics found that a common form of hair loss called androgenetic alopecia (male-pattern baldness) is associated with variations in a specific gene. 2 This means that if someone in your family has hair loss, you may also be at risk.

2. Hormone imbalance:
Hormonal imbalances are another factor that can contribute to hair loss. In men, a hormone called DHT (dihydrotestosterone) can cause male pattern baldness. This hormone negatively affects hair follicles, causing hair to become fine and prone to falling out. 3 In women, hormonal changes, such as those during pregnancy or menopause, can also contribute to hair loss.

3. Stress and Malnutrition
Stress and malnutrition are also known to be triggers of hair loss. Stress can cause hair follicles to become dormant, hindering normal hair growth. 4 Additionally, malnutrition and a lack of essential nutrients such as iron, protein, and vitamins can also cause hair to become brittle and prone to breakage. 5

4. Other factors:
In addition to the factors listed above, there are other factors that may contribute to hair loss. For example, certain medications (such as chemotherapy drugs), autoimmune diseases (such as alopecia areata), and head injuries can all cause hair loss. These factors are related to the individual's specific situation and lifestyle.

How to prevent hair loss?

1. Maintain good living habits:
Good living habits are essential for healthy hair. Here are some recommended habits67 :

  1. Eat a healthy diet: Make sure you eat a balanced diet with adequate nutrients, especially protein, iron, vitamins, and minerals. These nutrients are essential for hair growth.
  2. Moderate exercise: Maintaining moderate exercise helps promote blood circulation, including blood supply to the scalp, thereby promoting hair growth.
  3. Get enough sleep: Make sure you get enough sleep each night to promote repair in your body and growth of your hair.

2. Avoid excessive combing and pulling:
Over-combing and pulling on your hair can cause it to break and fall out. Therefore, avoid over-combing and using harsh combs, choose a comb with wide teeth, and comb your hair gently .

3. Use chemical products appropriately:
Hair dyes, perms, and certain chemical products contain harsh ingredients that can cause hair damage and hair loss. Use these products moderately, follow directions, and get regular hair repair treatments to reduce the risk of damage. 9

4. Reduce stress:
Stress is considered a trigger for hair loss. Effective stress management techniques, such as exercise, meditation, and relaxation techniques, can help reduce the negative effects of stress on hair. 10

Ways to Prevent Hair Loss - Is Caffeine Okay?

Some research suggests that caffeine may have a positive impact on hair loss. A study published in the International Journal of Dermatology found that caffeine can inhibit the production of a hormone called DHT (dihydrotestosterone), which is associated with male pattern baldness. 11 This suggests that caffeine may help slow the progression of male pattern baldness. Additionally, a study conducted by researchers at the University of Munich in Germany found that applying caffeine directly to the scalp can promote hair growth. 12

Notes:

  1. Hillmer AM, Brockschmidt FF, Hanneken S, et al. Susceptibility variants for male-pattern baldness on chromosome 20p11. Nat Genet. 2008;40(11):1279-1281. doi:10.1038/ng.248
  2. Heilmann-Heimbach S, Herold C, Hochfeld LM, et al. Meta-analysis identifies novel risk loci and yields systematic insights into the biology of male-pattern baldness. Nat Commun. 2017;8:14694. doi:10.1038/ncomms14694
  3. Trueb RM. Molecular mechanisms of androgenetic alopecia. Exp Gerontol. 2002;37(8-9):981-990. doi:10.1016/s0531-5565(02)00098-5
  4. Arck PC, Handjiski B, Hagen E, Joachim R, Klapp BF, Paus R. Indications for a 'brain-hair follicle axis (BHA)': inhibition of keratinocyte proliferation and up-regulation of keratinocyte apoptosis in telogen hair follicles by stress and substance P. FASEB J. 2001;15(13):2536-2538. doi:10.1096/fj.01-0314fje
  5. Schweiger ES, Boychenko O, Bernstein RM. Update on the pathogenesis, genetics and medical treatment of patterned hair loss. J Drugs Dermatol. 2010;9(11):1412-1419.
  6. Blume-Peytavi U, Vogt A. Hair loss: different pathophysiological aspects and some therapeutic approaches. J Dtsch Dermatol Ges. 2011;9(10):789-797. doi:10.1111/j.1610-0387.2011.07772.x
  7. Guo EL, Katta R. Diet and hair loss: effects of nutrient deficiency and supplement use. Dermatol Pract Concept. 2017;7(1):1-10. doi:10.5826/dpc.0701a01
  8. Messenger AG, Rundegren J. Minoxidil: mechanisms of action on hair growth. Br J Dermatol. 2004;150(2):186-194. doi:10.1111/j.1365-2133.2004.05785.x
  9. Draelos ZD. Hair care: an illustrated dermatologic handbook. 2nd ed. CRC Press; 2014.
  10. Arck PC, Handjiski B, Peters EM, et al. Stress inhibits hair growth in mice by induction of premature catagen development and deleterious perifollicular inflammatory events via neuropeptide substance P-dependent pathways. Am J Pathol. 2003;162(3):803-814. doi:10.1016/s0002-9440(10)63876-2
  11. Fischer TW, Hipler UC, Elsner P. Caffeine's mechanisms of action and its cosmetic use. Skin Pharmacol Physiol. 2007;20(4):195-202. doi:10.1159/000101807
  12. Otberg N, Teichmann A, Rasuljev U, Sinkgraven R, Sterry W, Lademann J. Follicular penetration of topically applied caffeine via a shampoo formulation. Skin Pharmacol Physiol. 2007;20(4):195-202. doi:10.1159/000101807