Dehydration Lines

Dehydration lines are a sign of a lack of water in the epidermis. They are fine, shallow lines that look like fine lines or wrinkles but are only there temporarily when the skin is not hydrated enough. They most commonly form around the eyes and forehead. You can reduce dehydration lines through increased water intake and applying hydrating products topically to the area.

Dermal Fillers

Dermal fillers are substances that are injected into the face to reduce wrinkles and increase volume. They can also be injected into the lips. Dermal fillers are usually made from hyaluronic acid and they are broken down by the body. They last around 6-18 months. Brand names of fillers include Juvederm, Restylane and Profhilo. Dermal fillers can and should only be performed by a licensed medical practitioner in the UK.


Dermatitis is a general term for skin irritation. It comes in many forms and has multiple causes but often presents itself as redness, dry skin, rashes, swelling or blistered skin. Dermatitis is not contagious.


The dermis is the middle layer of skin also known as the ‘true skin’. It is mostly comprised of collagen and elastin and is responsible for the strength and flexibility of the skin. The dermis also contains nerve endings, blood vessels, lymph nodes, sweat and sebaceous glands as well as hair follicles. Reduced collagen levels in the dermis result in loss of skin laxity, and wrinkles.


Dimethicone is a type of silicone that is used in personal care products to create a smooth product feel. It is also able to smooth the skin texture temporarily which is why it’s commonly used in primers. Dimethicone acts as a barrier over the skin so it can be used as a protective ingredient for harsh conditions such as strong winds or cold weather. 

Dry Skin

Dry skin is a skin type that does not retain enough moisture or produce enough oil. Symptoms of dry skin include flaking, tightness, itchiness and rough skin texture. Dry skin can be genetic or caused by lifestyle factors such as harsh skincare, pollution, medication, medical conditions, and other environmental stressors.