The beauty and health of our hair is often linked to one key concept: hair density. Hair density can be influenced by many factors, including heredity, stress and age. Find out how to measure hair density, what causes it to decrease and how to maintain or improve it.
What is hair density?
Hair density refers to the number of hair follicles per square centimetre. This measurement can be important in various contexts, such as assessing hair loss, evaluating the quality of the scalp for a hair transplant, or research into hair health and growth.
Hair density can vary considerably from one person to another depending on various factors, such as age, genetics, ethnicity and general health.
Hair density and hair volume: what are the differences?
Hair density and hair volume are two different concepts. While hair density refers to the amount of hair per square centimetre that a person has on their scalp, hair volume refers to the thickness and fullness of hair in general. It is influenced by hair density, but also by other factors such as hair type (curly, wavy, frizzy or straight), the thickness of each hair, the way the hair is styled or the use of certain styling products that add volume to the hair mass.
It is therefore possible to have high hair density but low volume, or vice versa. Both factors contribute to the overall appearance of the hair, but they are not synonymous.
How do you assess your hair density?
There are two main methods for assessing hair density. The first is to look at your hair from different angles to see how much of your scalp is visible through your hair.
If the scalp is easily visible, this indicates low hair density. If the scalp is partially visible, this suggests average hair density. On the other hand, if the scalp is almost or completely hidden by the hair, it probably means that the hair density is high.
The second technique for determining hair density is to gather all your hair into a ponytail and measure its circumference using a tape measure. A circumference of less than 5 centimetres indicates low hair density, a circumference of between 5 and 7.5 centimetres suggests medium density, while a measurement of over 7.5 centimetres implies high hair density.
What causes loss of hair density?
Loss of hair density can result from a number of factors. If the hair loss in men and female alopecia are mainly influenced by the genetic factor, age can also be blamed for loss of hair density. Over time, it is normal for hair to thin and for hair density to decrease.
Loss of hair density can also be caused by hormonal changes, such as those that occur during pregnancy or the menopause, or due to thyroid imbalances. A diet deficient in protein, iron, vitamin B and other nutrients can also weaken hair and lead to loss of hair density.
Telogen effluvium
Episodes of intense or prolonged stress, serious illness, surgery, childbirth, a drastic change of diet or major weight loss can cause temporary hair loss known as telogen effluvium.
To understand telogen effluvium, we need to look at the hair cycle. The hair growth cycle is divided into three main phases:
- The anagen phase: during this period, hair grows at a rate of 0.3 mm/day. The duration of this phase varies from several months to several years.
- The catagen phase: this is a transition period during which the hair stops growing and the hair follicle shrinks. This phase generally lasts between 3 weeks and several months.
- The telogen phase: this is the resting phase of the hair growth cycle, during which the hair does not grow but remains attached to the follicle. This phase lasts about 3 months, after which the hair falls out and are replaced by new hairs in the anagen phase.
Telogen effluvium occurs when more hair than normal enters the telogen phase of the hair growth cycle.
Telogen effluvium is usually temporary and hair often begins to grow back normally once the underlying cause has been resolved. However, in some cases it can last longer and develop into chronic telogen effluvium.
Traction alopecia
Traction alopecia is a form of hair loss that occurs when hair is constantly pulled and stressed by tight hairstyles or hair treatments. Ponytails, braids, dreadlocks, extensions and tight weaves are examples of hairstyles that can cause this type of hair loss.
How can I increase my hair density?
To increase your hair density, there are several options open to you: medical solutions, aesthetic medicine solutions and natural treatments.
Medical solutions
Many laboratories have developed treatments for hair loss. The two most widely used drugs in this field are Minoxidil and Finasteride.
- Minoxidil: this is a drug widely used to treat hair loss. It was originally developed as a drug to treat high blood pressure, but was found to have a side effect of hair growth.
- Finasteride: commonly used to treat androgenetic alopecia, it works by blocking an enzyme called 5-alpha-reductase, which converts testosterone into dihydrotestosterone (DHT). DHT is an androgen that contributes to the miniaturisation of hair follicles in genetically predisposed individuals, leading to hair loss.
Aesthetic medicine solutions
In aesthetic medicine, there are several solutions for treating hair loss and improving hair density:
- Platelet-rich plasma (PRP) injections: PRP is a platelet concentrate obtained from the patient's own blood, which is injected into the scalp. The platelets release growth factors that can stimulate tissue regeneration and hair growth.
- Mesotherapy: this procedure involves injecting a solution, which may contain vitamins, minerals, amino acids and other ingredients, into the scalp to stimulate hair growth.
- Laser treatment: this stimulates cellular activity in the hair follicles. Thanks to increased cell production, hair fibres can become thicker and healthier.
Natural solutions
If you prefer a more natural approach to improving hair density, there are several solutions to consider:
- Food supplements: although they should not be considered as hair loss solutions in their own right, food supplements are an effective support for hair health and beauty. For example, our Racines Plus vitamins provide your hair with all the nutrients it needs for healthy, balanced growth.
- A healthy diet: hair needs specific nutrients to grow in good health. Eat foods rich in protein, iron, zinc, B vitamins (especially biotin) and vitamin D.
- Hair care: Centre Clauderer offers a treatment based on natural products that are proven to be effective against hair loss, whether you are already suffering from baldness or have recently gone bald, and whatever your hair type. With a diagnosis, Clauderer's hair care programme offers you a specific treatment and tailor-made support to help you quickly regain healthier hair.
Jean-François Cabos is the creator of a unique hair care method based on the research he coordinated, which led to the publication of the book Hair, Roots of Life with Hélène Clauderer published by Robert Laffont (Collection "Réponses/ Santé").
