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- Clinical and Experimental Dermatology: Nutritional Factors and Hair Loss
- Clinical and Experimental Dermatology: Nutritional Factors and Hair Loss
- International Journal of Cosmetic Science: Causes of Hair Loss and the Developments in Hair Rejuvenation
- International Journal of Cosmetic Science: Causes of Hair Loss and the Developments in Hair Rejuvenation
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Can Amino Acids Affect Hair Loss?
You usually lose about 100 hairs per day naturally, but if you find yourself losing a lot more, nutrition could be to blame. While hormones, such as low thyroid or high levels of testosterone, may be the cause, too little protein or iron can also affect hair's health. Protein is made up of amino acid building blocks, some of which your body can produce and others that you must get from your diet. If your doctor determines you're low in iron, your hair loss may also be compounded by a less-than-optimal intake of the amino acid L-lysine.
About L-Lysine
L-lysine is one of eight essential amino acids, those that your body cannot produce on its own. It's found in complete proteins, including red meat, poultry, pork, eggs, cheese, certain fish -- particularly cod and sardines -- and soybeans. Nuts, legumes and brewer's yeast are vegetarian sources of the amino acid. If you're following a very-low-calorie diet without a lot of protein or a vegan diet that doesn't contain adequate nuts and beans, you could be deficient in this amino acid.
- L-lysine is one of eight essential amino acids, those that your body cannot produce on its own.
- If you're following a very-low-calorie diet without a lot of protein or a vegan diet that doesn't contain adequate nuts and beans, you could be deficient in this amino acid.
Effects on Hair Loss
Does Red Meat Cause Thinning Hair?
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Hair loss is a known symptom of iron deficiency. A paper published in a 2002 issue of "Clinical and Experimental Dermatology" noted that increased hair loss corresponds with iron deficiency and suboptimal intakes of L-lysine 4. When subjects are given iron supplements and lysine supplements, hair shedding decreased. It may take several months, though, to notice changes in your hair after you start taking these supplements.
- Hair loss is a known symptom of iron deficiency.
- A paper published in a 2002 issue of "Clinical and Experimental Dermatology" noted that increased hair loss corresponds with iron deficiency and suboptimal intakes of L-lysine 4.
Overall Low Protein
L-lysine is one major amino acid that could explain hair loss, but an overall protein deficiency may as well. Because proteins are made up of amino acids, including L-lysine, the hair loss could result from low L-lysine levels or from a deficiency in any one of the other essential amino acids. The Institute of Medicine recommends you get 10 percent to 35 percent of your daily calories from protein or a minimum of 0.36 grams of protein per pound of body weight each day. If you weigh 140 pounds, you should aim for about 50 grams per day. Those with eating disorders, on crash diets or with certain conditions that prevent nutrient absorption are prone to not getting enough protein, and potentially losing hair as a result.
- L-lysine is one major amino acid that could explain hair loss, but an overall protein deficiency may as well.
Too Much of a Good Thing
Recommended Dose of L-Lysine
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Getting too much of particular supplements can also cause excessive hair loss. Excessive vitamin A supplementation, for example, is one potential cause. Consult with your doctor to ensure you have a true deficiency before adding supplemental amino acids or vitamins and minerals to your diet.
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References
- Hair Care: An Illustrated Dermatologic Handbook; Zoe Diana Draelos
- Nutrition ATC: Hair Loss in Women Has Contributing Factors
- University of Maryland Medical Center: Lysine
- Clinical and Experimental Dermatology: Nutritional Factors and Hair Loss
- Dr. Oz: Fight Fatigue: Reverse Your Iron Deficiency
- International Journal of Cosmetic Science: Causes of Hair Loss and the Developments in Hair Rejuvenation
- Fabbrocini G, Cantelli M, Masarà A, Annunziata MC, Marasca C, Cacciapuoti S. Female pattern hair loss: A clinical, pathophysiologic, and therapeutic review. Int J Womens Dermatol. 2018;4(4):203-211. doi:10.1016/j.ijwd.2018.05.001
- Mirmirani P. Managing hair loss in midlife women. Maturitas. 2013;74(2):119-22. doi:10.1016/j.maturitas.2012.10.020
- Trost LB, Bergfeld WF, Calogeras E. The diagnosis and treatment of iron deficiency and its potential relationship to hair loss. J Am Acad Dermatol. 2006;54(5):824-44. doi:10.1016/j.jaad.2005.11.1104
- Park SY, Na SY, Kim JH, Cho S, Lee JH. Iron plays a certain role in patterned hair loss. J Korean Med Sci. 2013;28(6):934-8. doi:10.3346/jkms.2013.28.6.934
- 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
- Vincent M, Yogiraj K. A Descriptive Study of Alopecia Patterns and their Relation to Thyroid Dysfunction. Int J Trichology. 2013;5(1):57-60. doi:10.4103/0974-7753.114701
- Davis SR, Castelo-branco C, Chedraui P, et al. Understanding weight gain at menopause. Climacteric. 2012;15(5):419-29. doi:10.3109/13697137.2012.707385
- Gupta AK, Charrette A. Topical Minoxidil: Systematic Review and Meta-Analysis of Its Efficacy in Androgenetic Alopecia. Skinmed. 2015;13(3):185-9.
- American Academy of Dermatology. Thinning hair and hair loss: Could it be female pattern hair loss?
- Harvard Health Publications. Treating female pattern hair loss - Harvard health.
- U.S. National Library of Medicine. Female pattern baldness.
Writer Bio
Andrea Cespedes is a professionally trained chef who has focused studies in nutrition. With more than 20 years of experience in the fitness industry, she coaches cycling and running and teaches Pilates and yoga. She is an American Council on Exercise-certified personal trainer, RYT-200 and has degrees from Princeton and Columbia University.