01/20/2026
What Is the Skin and how it affects my health?
Your skin is the largest organ of your body. It's made up of several different substances, including water, protein, lipids, minerals and chemicals. The average adult's skin weighs about 6 pounds. Its job is crucial — to protect you from infections and germs. Throughout your life, your skin changes constantly, for better or worse. In fact, your skin regenerates itself approximately every 27 days. Proper skin care is key to maintaining the health and vitality of this crucial organ.
Functions of Skin
The skin has many more functions than you might imagine. Here are some of them:
1. Protective barrier. This is the most obvious function. The skin protects your body against water
loss, invasion of bacteria and other germs, physical injuries, chemical damage, and UV light.
2. Immune defense. Your skin helps your immune system fight off infections by producing substances that kill bacteria and fungi. Your skin contains cells that alert the body’s immune system to threats.
3. Keeping your body in balance. That means regulating your body temperature and its water balance. Sweat glands and blood vessels in your skin try to make sure you don't get too hot or too cold.
4. Production of Vitamin D. When exposed to sunlight, your skin produces vitamin D. This vitamin is important for healthy bones and helps the immune system fight off infections.
5. Sensory function. Your skin has sensors that can detect touch, heat, cold, and pain. This helps protect you against harm and allows you to interact with your surroundings without injuring yourself.
Your skin is a complex organ. Explore its layers and how each functions, from the epidermis to the subcutis. Learn key tips for healthy skin and the roles of collagen, elastin, and keratin.