What is skin?

Your skin is your body's largest organ. It works as a protective covering for your body. Your skin is tough and flexible and helps protect your internal organs from the outside world.

What are the parts of the skin?

Your skin covers your body and has 3 layers:

• The top layer is called the epidermis. This is a thin layer that provides a waterproof barrier for your body. It also contains cells called melanocytes that give your skin colour.
• The dermis is the middle layer of skin. It is much thicker than your epidermis. It contains tough connective tissue, blood vessels, nerves, hair follicles and sweat glands.
• Under the dermis is the subcutaneous layer. This layer contains fat and large blood vessels.

What are the functions of skin?

Your skin has many functions:

• Your skin protects you against bacteria, viruses, and parasite infections as a part of your immune system.
• It shields your body from harm caused by injuries and chemicals.
• By preventing loss of water and body fluids, skin helps control your body temperature.
• Skin allows you to feel things, such as heat, cold, touch, pain, and vibration.

Skin absorbs ultraviolet (UV) light from the sun, which you need to make vitamin D. Vitamin D is important for good bone health. Most Australians can get enough vitamin D through safe exposure to the sun.

The Sunshine Map tells you how much sunlight you need depending on where you live.

What are some common skin problems?

Skin conditions affect people differently. Some common skin conditions include:

• acne
• cellulitis
• eczema or dermatitis
• psoriasis
• rosacea
• hives (urticaria)
• warts

Skin conditions can be caused by:

• allergies or irritants
• insect bites
• bacterial, fungal or viral infections
• stress
• hormonal imbalance
• a build-up of sweat or oil on the skin

Skin conditions can also occur due to problems with your immune system. Smoking, drinking alcohol, and some medicines may worsen your skin condition.

Treating acne early can reduce the impact on your mental health and reduce the risk of scarring.

Moles, lesions, and skin cancer

Skin cancer occurs when skin cells are damaged, for example, by too much UV radiation from the sun.

Your risk of skin cancer increases with age, and factors like sunburn, tanning, and using solariums (sun beds).

Common skin cancers include:

• basal cell carcinoma
• squamous cell carcinoma
• melanoma

You might have freckles, moles, and other lesions such as skin tags on the surface of your skin. Most moles and marks on your skin are harmless, or benign. Some types of moles have a higher chance of developing into cancer. These moles may:

• change in size, shape, texture or colour
• look different from other moles
• be itchy or bleed
• be a sore that doesn't heal within a few weeks
• appear crusty or flaky

See your doctor if you have any suspicious skin lesions.

CHECK YOUR SYMPTOMS — Use the Symptom Checker and find out if you need to seek medical help.

How does ageing affect your skin?

As you age, your skin changes. There are less elastic and collagen fibres and more obvious wrinkles. These changes can be increased by too much sun exposure.

As skin ages, it might show:

• fine lines and wrinkles
• thinner skin
• more visible blood vessels
• dryness, due to less oil being produced

How can you maintain healthy skin?

Here are some tips to help keep your skin healthy:

• Protect your skin from the sun.
• Don't smoke.
• Treat your skin well by keeping it moisturised.
• Eat a balanced diet.
• Manage your stress.
• Check your skin for any suspicious moles regularly.

Protect your skin from the sun

Exposure to UV radiation from the sun is the most common cause of skin cancer.

Skin cancers are the most common types of cancer in Australia. If you need to go out in the sun, it's important to protect your skin if the UV index is 3 or above.

How often should you get your skin checked?

It's important to check your skin regularly. If you have any health concerns with your skin or notice any changes, you should see your doctor. Early treatment of cancers can provide a better outcome.

Your doctor can:

• give you a skin check
• take a skin sample (biopsy) to help diagnose skin problems
• remove moles and benign lesions on your skin
• treat or remove any skin cancers
• treat and manage other skin conditions

Your doctor can also refer you to a dermatologist, a skin specialist, if needed.

FIND A HEALTH SERVICE — The Service Finder can help you find doctors, pharmacies, hospitals and other health services.

Resources and support

The Cancer Council has resources about skin cancer and how to check your moles.

Skin Cancer Hub details the importance of regular skin checks and the risk factors for melanoma.

For more information about ageing skin visit The Australasian College of Dermatologists.

All about acne has easy to read resources about acne.

The Australasian College of Dermatologists 'Find a dermatologist' search tool helps you locate a dermatologist nearby and learn about their specialties.

Languages other than English

Health Translations has translated resources about skin conditions and how to be sun safe.

You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with you 24 hours a day, 7 days a week.