Mehendi, or henna, has long been a preferred natural dye for hair colouring. Used for centuries, it is cherished for its ability to impart a rich reddish-brown hue while also conditioning the hair. Unlike synthetic dyes, mehendi is often perceived as a safe and chemical-free alternative. However, using mehendi frequently to colour hair can have adverse effects that are often overlooked. While it may seem like a natural and harmless solution, excessive use can lead to severe hair and scalp issues. Below, we explore some of the hidden dangers of colouring your hair with mehendi too often.

Excessive dryness and brittleness

One of the most common side effects of using mehendi frequently is excessive dryness. Mehendi contains tannins that can strip the hair of its natural oils, leading to rough and brittle strands. While it initially provides a smooth texture, repeated applications can sap the hair’s moisture, making it prone to breakage and split ends. Over time, this can result in unmanageable, frizzy hair that lacks shine and elasticity.

Alteration of natural hair texture

Frequent use of mehendi can change the natural texture of your hair. People with naturally soft and silky hair may notice a coarse and rough texture developing over time. Mehendi coats the hair shaft with its colour, making hair appear thicker. However, excessive coating can weigh down the strands, leading to stiffness and an unnatural, straw-like feel.

This change in texture can make styling difficult and diminish the hair’s overall health.

Hair thinning and breakage

Many believe that mehendi strengthens hair, but overuse can have the opposite effect. The drying nature of mehendi can weaken the hair shaft, making it brittle and prone to breakage. In extreme cases, frequent application may contribute to hair thinning and hair fall, as the scalp struggles to retain its natural moisture and nourishment.

Allergic reactions and scalp sensitivity

Despite being natural, mehendi can cause allergic reactions in some individuals. Continuous exposure to mehendi can lead to scalp irritation, redness, itching, and even rashes. Some people develop contact dermatitis, an inflammatory skin condition triggered by prolonged exposure to certain natural or synthetic substances. Individuals with sensitive scalps are particularly vulnerable to these reactions, making it essential to perform a patch test before every application.

Unwanted colour build-up and uneven tones

Frequent use of mehendi can lead to excessive build-up of colour on the hair, resulting in an unnatural and uneven hue. Since mehendi does not fade easily, repeated applications can cause darker and sometimes patchy staining, which can be difficult to correct. Unlike chemical dyes that can be toned down, mehendi’s stubborn colour makes it hard to switch to a different shade or remove entirely without causing further damage.

Difficulties in switching to other hair colours

One of the biggest drawbacks of frequent mehendi use is that it makes it nearly impossible to colour hair with synthetic dyes later. The natural henna coating creates a barrier that prevents chemical dyes from penetrating the hair shaft. This often results in unpredictable colour outcomes, such as green or orange tints, when trying to transition to synthetic hair colours. To remove mehendi, harsh chemical treatments or multiple bleaching sessions may be required, which can severely damage the hair.

Presence of impure or adulterated mehendi

Not all mehendi is pure. Many commercial mehendi powders contain added chemicals, metallic salts, or synthetic dyes to enhance colour longevity and intensity. These additives can cause severe allergic reactions, scalp burns, and hair damage over time. Black henna, often marketed as an alternative to pure mehendi, contains para-phenylenediamine (PPD), a harsh chemical that can cause severe skin irritation, blistering, and long-term allergic sensitivities.

Overburdening the scalp and hair follicles

Frequent applications of mehendi can clog hair follicles, leading to buildup on the scalp. This buildup prevents essential nutrients and oxygen from reaching the hair roots, potentially causing hair thinning and hindering new hair growth. A scalp that is constantly coated with mehendi may also suffer from excessive dryness or irritation, disrupting the natural balance required for healthy hair growth.

How to minimise the side effects of mehendi

While mehendi can be a great natural alternative to chemical dyes, moderation is key. Here are some ways to mitigate its side effects:
Limit application Frequency: Use mehendi only once every two to three months to prevent excessive dryness and buildup.

Choose pure mehendi: Always opt for 100% pure, organic mehendi without chemical additives.
Deep conditioning treatments: Follow up with deep conditioning or oiling treatments after using mehendi to restore moisture.
Avoid black henna: Stay away from products labeled as “black henna,” as they often contain harmful chemicals.

While mehendi remains a popular choice for natural hair colouring, using it frequently can lead to a variety of hair and scalp issues. From excessive dryness to difficulty in switching hair colours, overuse can take a toll on hair health. Being mindful of application frequency and ensuring the use of pure mehendi can help maintain hair’s natural beauty while avoiding unwanted side effects. As with any beauty treatment, balance and caution are essential to achieving the best results without compromising hair health.