Tag: hair

October’s QOM- Can Apple Cider Vinegar replace shampoo?

 

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Dear Hair Doctor: What is your medical opinion on replacing traditional shampoo with Apple Cider Vinegar? Can it really help with dandruff and itchy scalp? Are there any benefits for tightly coiled black hair?

 

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I don’t think Apple Cider Vinegar is that useful as  a complete replacement for shampoo as it cannot effectively remove oils etc from your hair that well because of its chemical properties.   See this blog post from another scientist :

http://www.thenaturalhavenbloom.com/2014/07/can-you-wash-your-hair-with-baking-soda.html

Apple Cider Vinegar has been used traditionally as a final rinse to close the cuticle, make the hair shiny, and to remove any residual soap deposits from the hair. People used to wash their hair with soap (as well as with other naturally saponin rich plants like soapwort and aloe vera). Because Apple Cider Vinegar is acidic it helps to restore the pH of the scalp and hair, and in the process tackles excess flaking (dandruff). For highly textured hair, in women of African descent, it is quite useful as it helps to restore the pH which would be significantly changed once exposed to high pH shampoos and soaps. This renders this hair type rough and make it extremely unmanageable. Once the pH is restored the hair will be more likely to act better.

 

About 

Dr. Llorenia Muir-Green is a practising dermatologist in Jamaica. She has an avid interest in hair and scalp disorders.  She is a member of the Medical Association of Jamaica,  Dermatology Association of Jamaica and is an Associate Member of the Caribbean Dermatology Association. She was a recipient of the 2013 Fellowship in Hair and Scalp Disorders at the University of British Columbia.

The Hair Growth Cycle

The Hair Growth Cycle has three main phases: Anagen (growth) phase, Telogen (rest) phase, Catagen (degeneration) phase. Recently there has been an additional process described, called Kenogen. Human hair growth cycle is unlike the animal hair growth cycle as each invidual hair cycles independently of those beside it. However, at any point in time, 90% of hairs are found to be in anagen, roughly 10% in telogen and a miniscule amount in catagen.

hair_growth_phases

Anagen

Anagen is also called the “growing phase”.  It is a genetically predetermined time period when the follicle is active. This time period can last from 2-6 years. Each area of the body has a predetermined anagen phase.  This is why your chest hairs don’t normally grow as long as those on your head.

 

Catagen

This is a degenerative process where the dermal papilla (that part of the hair follicle responsible for producing the proteins which will form the hair shaft), will start to degenerate and be destroyed. Typically, hair growth stops and the hair follicle is broken down as the hair shaft detaches from the dermal papilla stem cells. It is typically referred to as the “dying phase” in the hair growth cycle. It usually lasts for a few weeks.

 

Telogen

This is where the hair then goes into a suspended “resting phase” and the club hair is formed. It usually lasts about 3 months. This hair will be gradually pushed out once the new hair in anagen will grow and force it out. Telogen hairs are easily removed from the scalp. This is why when you comb your hair you will remove some. Even more are removed when you wash your hair simply because of the greater amount of manipulation of the hair during the shampoo process. A normal amount that is shed is 50-150 hairs a day.  Naturally shed hairs have a white bulb on them (typical club hair).

 

The Hair Doc

Dr. Llorenia Muir-Green is a practising dermatologist in Jamaica. She has an avid interest in hair and scalp disorders.  She is a member of the Medical Association of Jamaica,  Dermatology Association of Jamaica and is an Associate Member of the Caribbean Dermatology Association. She was a recipient of the 2013 Fellowship in Hair and Scalp Disorders at the University of British Columbia.

August’s QOM- What’s the difference between dry scalp and dandruff?

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Hey Doc, need some help. How do u differentiate between dry scalp and dandruff, and what’s the treatment for each? What causes or aggravates them? Pls help.

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A completely dry scalp i.e. where there is no oil and the skin cracked is actually not common.  There are persons who have genetic and other unusual skin disorders where all of their skin including their scalp is dry. What people often refer to as “dry scalp” is actually dandruff. A flaky scalp does not necessarily mean it is dry. There are also other conditions that can result in a flaky scalp: psoriasis, discoid lupus and other scarring type hair loss.

For most persons they are experiencing  seborrhoeic dermatitis which most often refer to as dandruff. Seborrhoeic dermatitis is caused by inflammation of the scalp caused by a fungus that lives on the scalp that feeds on the sebum that our scalp hairs produce. The scalp produces a lot of sebum even more than the face. Your hair type which is excessively curly does not make you be aware of it. For other races with straighter hair it is quite obvious how oily their hair can get. You actually do not need to oil the scalp ever.

The number one thing to alleviate dandruff is to wash your hair often. Do not go a week without washing your hair. You will see a difference in how your scalp reacts. Antifungal shampoos used directly on the scalp can be helpful. Ketoconazole, Selenium sulfide, Zinc Pyrithione II, and Tea tree oil containing shampoos are helpful. Leave them on for ten minutes. Rinse then wash your hair with the regular shampoo afterwards. 

 

About

Dr. Llorenia Muir-Green is a practising dermatologist in Jamaica. She has an avid interest in hair and scalp disorders.  She is a member of the Medical Association of Jamaica,  Dermatology Association of Jamaica and is an Associate Member of the Caribbean Dermatology Association. She was a recipient of the 2013 Fellowship in Hair and Scalp Disorders at the University of British Columbia.

Have a question you would like to be answered? Send in your question to ask@askthehairdoc.com. Remember to follow me on Facebook, Twitter, Instagram and Google Plus.

Properties of Hair – Part 3

In the third installment of the properties of hair, lipid or fat content of the hair shaft will be our subject. The lipid content of hair is approximately 1-9% .

The lipids found in hair are tightly bound to the proteins via various bonds, and as such, are referred to as Integral Hair Lipids.  They confer resistance  to the hair shaft, protecting it from the environment by forming a lipid envelope. Most of the lipids are found in the the hair cuticle and inner root sheath. Major constituents are fatty acids, phytosphingosine, and ceramide in decreasing order. Minor constituents are cholesterol, cholesterol sulfate and cholesterol oleate. Interestingly the lipid components differ from the skin to hair follicle to the hair shaft.

Table showing lipid constituents in hair and skin compartments

Sebum % Epidermis % Hair mg/g Hair mg/g Follicle %
Free cholesterol 5 26 ± 0.6 0.5 0.5 3.7
Free fatty acid 13.1 ± 1.6 4.0 23.4 29.6
Cholesterol sulfate 3.9 ± 1.4 2.9 0.4 0.3
Triglyceride 57 0.2
Cholesterol esters 5 1.7 ± 1.1
Glucosylceramide 1.0 ± 0.6
Unidentified 5.7 ± 0.9
Sphinghosine 26.3
Wax ester 26 4.1
Squalene 12 <0.2

The major fatty acid, representing 40% of the total fatty acids, is identified as 18-methyleicosanoic acid. The next abundant are palmitic acid and stearic acid. Alkaline treatments (hair colorings, bleaching, perms) or sunlight can lead to a loss of 18-MEA and causes the defatting of hair. As such, the hair becomes dry and brittle and loses its elasticity and luster.

They all serve to decrease the friction between the hair strands. Their role in hair are slowly being delineated. Their presence may indicate something more important with respect to the functioning of the body. Ceramide production has been found to decrease with age. Also, it has been found that errors in lipid metabolism could result in abnormal skin and hair diseases.  As more and more research is done, we shall see the exact role they play in hair.

Properties of Hair- Part 2

Though it may not be that obvious, water is an important component of hair. Its presence helps with the elasticity or pliability of hair. The water content of hair is between 15-35%. The high variability is due to the hairtype and health of the hair fibre. Hair that is damaged is less likely to hold onto water. ‘

Water has the potential to increase not only the weight of the hair fibre but also the diameter. This is referred to as the swelling potential of hair. It can increase to nearly 14% in diameter, but less than 2% in length. Other reagents such as sodium lauryl sulfate, formic acid, and thioglycolic acid have a greater effect on the swelling potential of hair, hence the reason for these products to potentially damage hair.

The more the hair absorbs is the more damaged the hair, indicating that the hair shaft is more porous. This is what is  termed as “porosity”.  Hair that absorbs more water has decreased tensile strength i.e. it easily breaks. The porosity of the hair shaft is about 20%, allowing a weight increase of 12–18% when soaked in water. The absorption rate is very rapid, with 75% of the maximum absorbable water entering the hair shaft within 4 minutes.

However, as quickly as the hair absorbs water, it can quickly lose it. Those with quite porous hair can attest to this. Water has been shown to stay in the hair shaft better if attached to some highly osmotic molecule like sorbitol, or some other hygroscopic (water-loving) substance such as glycerin. These molecules allow water from the atmosphere to stay longer in contact with the hair shaft. This increases the moisture content of the hair shaft and thus allows the hair to not only feel better but to look better as well.

References

Syed AN, Ayoub H. Correlating Porosity and Tensile Strength of Chemically Modified Hair. Cosmet Toil 2002; 117: 57-64.

Draelos MD, Zoe Diana (2007-04-17). Hair Care (Kindle Locations 331-334). Informa Healthcare. Kindle Edition.

Egawa, M., Hagihara, M. and Yanai, M. (2013), Near-infrared imaging of water in human hair. Skin Research and Technology, 19: 35–41