Everyone loves soft, bouncy hair that’s strong and doesn’t break easily. But increasing the hair’s tensile strength can be quite challenging and demands a proper hair care routine.
Hair fall is a common issue in many people. One of the reasons behind hair loss is an increase in hair breakage due to the lessening of tensile strength of the hair fiber. (1)
Your hair is made of a natural fiber composed of keratin, which is a protein that contains a higher concentration of sulfur derived from the amino acid cysteine.
Keratin is a laminated compound with different structures that gives your hair strength, flexibility, sturdiness, and functionality. (2) The hair cuticles enclose the cortex, the central part of hair mass. The cortex is the one that provides hair tensile strength. (3)
What Do You Mean by the Tensile Strength of Hair?
The hair’s tensile strength is the maximum stress level (force per unit area) that the hair can bear while being stretched or pulled before breaking.
Elasticity is solid materials’ tendency to return to their original shape after getting deformed. Hair fiber is elastic. Its elasticity increases with the hair keratin’s affinity for water.
When hair remains dry, it can stretch up to 20%–30% of its original length, and when it comes in contact with water, it can stretch up to 50% of its original length. Water in the hair can be retained if oil is applied immediately after washing it.
Oil can elevate hair elasticity as it is a conditioner that can help in locking in moisture into the hair strands. The presence of both oil and moisture in the hair has an impact on its tensile strength and breaking point. (1)
Tips for Increasing Hair Tensile Strength
You can increase the tensile strength of your hair by following these measures.
1. Following a balanced diet and adequate nutrition
A balanced diet rich in essential nutrients helps to raise the tensile strength of your hair.
Include iron-rich fruits in your diet, such as pomegranate, amla, dried figs, dates, and leafy vegetables, which can upgrade the strength and quality of your hair.
Also, include vitamins A, B, C, D, E, and H (biotin) in your daily intake to repair your weak hair roots. It would help if your everyday meals consisted of dry fruits and nuts such as walnuts and almonds. (4)
According to a small study done in 2015, cystine is a candidate when considering the right nutritional intake for enhancing hair growth in humans. Taking dietary supplements is the best way to fulfill all your nutritional requirements.
Taking L-cystine with B complex vitamins is best for your hair’s optimal growth. Some studies have shown that dietary supplements with such a combination resulted in great improvements in the trichogram and hair tensile strength. (5)(6)
2. Protecting your hair from UV rays
Exposure to UVB radiation is never healthy for your hair and can pose severe damage, such as breaking down the disulfide bonds that are necessary for hair structural integrity.
These disruptions can cause severe damage to your hair’s mechanical properties, instantly resulting in loss of tensile strength, enhancing porosity and thus irregularities on the hair surface. (7)
3. Using your fingers to untangle hair
Hair tangling occurs when your hair gets damaged and dry. When the hair cuticle layer is damaged and excessively porous, the follicle breaks easily and cannot restore moisture, causing frizz and hair dryness.
Use your fingers to work on your tangles first before brushing them out. This is a gentle way of untangling and will cause less damage. Start detangling your hair from its ends and slowly work upward to prevent hair damage.
4. Effectively washing your hair
When your hair is porous and damaged, proper hair care, including properly washing the hair, is needed. Water absorption results in swelling of the hair shaft.
Excessive or repetitive chemical treatments, damaging grooming habits, exposure to environmental agents, and other such factors can bring negative changes in the hair texture (8) and consequently hair breakage.
So properly washing your hair is recommended as a recent research study done in 2021 showed higher wash frequency (5 times per week) is both beneficial for scalp and hair condition. (9) Use mild shampoo for washing your hair.
5. Limiting the use of heating tools
Using heating tools frequently on your hair dries it out due to the excessive heat. It has been observed that using a hair dryer causes more damage to the hair surface than natural drying.
These heating techniques are harmful to the integrity of your hair fiber protein and can compromise your hair’s tensile strength. (8)
6. Avoiding bleaching
Recent studies have shown that the hair cortex has the most significant effect on hair tensile strength. The melanin responsible for hair color is present in the hair cortex. Using bleaching agents on your hair has harmful effects as it destroys the hair structure through the cortex and fades the hair color. (10)
Regular bleaching involves the use of chemicals such as hydrogen peroxide, ammonia, and persulfate salts, which lightens the hair color permanently. These oxidizing agents in alkaline solutions penetrate the hair cortex, elevating the scales of the hair cuticles and thus modifying the melanin chemically.
Repetitive bleaching treatments can lead to increased hair porosity and permanently elevated scales. They can lead to hair weathering, which in turn reduces the hair’s tensile strength. (11)
What Is the Maximum Tolerable Tensile Strength for Human Hair?
The maximum tensile strength of human hair is in the range of 200–250 MPa, beyond which hair can break and may not be able to regain its strength.
You can measure the tensile strength of your hair by handling the single strands of hair which must have a diameter of around 0.025 mm to 0.076 mm. (12)
Factors Affecting the Tensile Strength of Hair
Hair’s tensile strength is influenced by:
- Twisting and stretching
- Hair diameter
- Weaving and grooming
- Physical stress during hair styling and combing (13)(14)
General Queries Related to the Tensile Strength of Hair
Does the tensile strength change with hair size?
Yes, the hair’s tensile strength can increase with the reduction in the diameter of the hair. (12)
Does hair have tensile strength?
Hair displays a high tensile strength of 150–270 MPa, which depends on the external pressure rate (such as stretching, pulling, and combing), humidity, and temperature. (15)
Weak hair roots need to be managed internally and externally. Your diet and hair care routine are equally essential to increasing the tensile strength of your hair.
Hair strength largely depends on the nature of the intermolecular bonds in your hair. The more intermolecular bonds, the firmer the hair and, thus, the higher its tensile strength. Give the above-given tips a try to increase your hair’s tensile strength.
- Kavitha S, Natarajan K, Thilagavathi G, Srinivas CR. Effect of oil application, age, diet, and pigmentation on the tensile strength and breaking point of hair. International journal of trichology. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5387873/. Published 2016.
- Hair fiber characteristics and methods to evaluate hair … – scielo. https://www.scielo.br/j/bjps/a/XZrwDJrKKXh4Q3JwswHJ4vq/?format=pdf.
- Cruz CF, Costa C, Gomes AC, Matamá T, Cavaco-Paulo A. Human hair and the impact of cosmetic procedures: A review on cleansing and shape-modulating cosmetics. MDPI. https://www.mdpi.com/2079-9284/3/3/26/htm. Published July 25, 2016.
- Guo EL, Katta R. Diet and hair loss: Effects of nutrient deficiency and supplement use. Dermatology practical & conceptual. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5315033/. Published January 31, 2017.
- Rizer RL, Stephens TJ, Herndon JH, Sperber BR, Murphy J, Ablon GR. A marine protein-based dietary supplement for subclinical hair thinning/loss: Results of a multisite, double-blind, placebo-controlled clinical trial. International journal of trichology. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4738482/. Published 2015.
- Trüeb RM. “Let food be thy medicine”: Value of nutritional treatment for hair loss. International journal of trichology. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8647708/. Published 2021.
- James.firstname.lastname@example.org, James.email@example.com. Impact of environmental stressors on hair. NYSCC. https://nyscc.org/blog/impact-of-environmental-stressors-on-hair/. Published July 12, 2021.
- Gavazzoni Dias MFR. Hair cosmetics: An overview. International journal of trichology. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4387693/. Published 2015.
- Punyani S; Tosti A; Hordinsky M; Yeomans D; Schwartz J; The impact of shampoo wash frequency on scalp and hair conditions. Skin appendage disorders. https://pubmed.ncbi.nlm.nih.gov/34055906/.
- Effect of phyllanthus emblica Linn. on tensile strength of virgin and … https://www.researchgate.net/publication/344423595/.
- Alessandrini A, Piraccini BM. Essential of hair care cosmetics. MDPI. https://www.mdpi.com/2079-9284/3/4/34/html. Published September 27, 2016.
- Yang W, Yu Y, Ritchie RO, Meyers MA. On the strength of hair across species. Matter. https://www.sciencedirect.com/science/article/pii/S2590238519302346. Published December 11, 2019.
- Tensile strength of scalp hair in women with hair loss – researchgate. https://www.researchgate.net/publication/347382097/.
- Healthy hair: What is it? – core. https://core.ac.uk/download/pdf/82270141.pdf.
- MA; YYYWWBM. Structure and mechanical behavior of human hair. Materials science & engineering. C, Materials for biological applications. https://pubmed.ncbi.nlm.nih.gov/28183593/.