There are some common beauty product ingredients that can cause adverse side effects if used carelessly or excessively. Some should be avoided altogether because research has shown that they are not safe. The Saturday Magazine beauty team spoke to Dr Peninah Kitili, a dermatologist in private practice. She said that there are indeed cosmetics products that are contraindicated for use.

This means that they ought to be used with utmost care. Some of the most commonly used include:

1.Black henna:  This is a chemical dye with a misleading name, totally different from real henna which is orange with red or brown undertones.

It is often used to decorate or tattoo skin in salons, but it contains a chemical called paraphenylenediamine which can cause irritation or allergic reaction. Option:  Use natural henna or proper tattooing ink.

2. Acetone: This is a liquid solvent found in nail polish removers. While removing the polish, it also dissolves the oil from your nails and fingers leading to dry and brittle nails. Constant use of acetone-based nail polish remover leads to weak nails. Option: Use acetone-free remover or add oil to your remover. Do not use remover more than once a week. After using, ensure that you massage some oil into your nails and cuticles.

3. Formaldehyde: This ingredient is used as a preservative in shampoo. When you read the labels, you should look out for ingredients like formaldehyde, quaternium-15, diazolidinyl urea, imidazolidinly urea and DMDM hydantoin which release formaldehyde. Research has proven that it is carcinogenic. Option: Use shampoo that has been preserved with ingredients such as citric acid.

4. Talc: This is the ingredient used to formulate powders. A naturally occurring mineral, it can sometimes contain traces of asbestos, a substance that can cause cancer when inhaled. It is suspected to cause respiratory problems when inhaled. Option: Use natural cornstarch as an alternative to (baby) powder.

5. Synthetic fragrances: Fragrance can cause allergies, watery eyes and minor skin irritation. People with sensitive skin are prone to these effects when they use products with strong perfumes. Option: Opt for fragrance-free products, or products with very mild scents.

6. Essential oils:  These oils are used for their therapeutic benefits to the body. However, incorrect use can lead to severe skin irritation. Sometimes, they are used like perfume.  For example, bergamot oil, but this should never be applied directly to sun-exposed skin. Others should not be used during pregnancy. Option: Select the oils carefully and dilute them with carrier oils according to the instructions. 

7. Sodium and calcium hydroxide/ammonium thioglycolate: These are the chemical names for hair relaxers. They are caustic and are known to cause various side effects such as chemical burns and blindness (if they come to contact with the eyes), due to their alkaline content. Do not use them at home. Avoid contact with eyes and unprotected skin and always ensure that you have neutraliser on standby when using.