Simply put, our skin is a protective barrier between our inner organs and the outside world. As the body’s largest organ, it plays a crucial role in maintaining our overall well-being. Whenever our skin shows signs of imbalance or irritation, it serves as a mirror reflecting potential underlying health issues. To understand how to take better care of our body and skin, it’s important to first understand the basics of how it works, how it heals, and how it protects us. So let’s delve into the magnificent world of skin.
Skin in numbers
- Skin’s area is approximately 2 square metres (22 square feet) for grown ups.
- Your skin weight is about 6-9kg (13.2-19.8 pounds), which makes up about 15% of our total body weight.
- Thickness varies from 0.5mm (0.02 inches) on eyelids to 4mm (0.16 inches) on your heels.
- One square inch of your skin has approximately 19 million skin cells, 1,000 nerve endings, 20 blood vessels and 100 oil glands.
- On average, your skin renews itself every 28 days, depending on a person’s age.
- Your skin sheds about 50,000 dead skin cells every minute, which adds up to around 8 pounds of skin cells per year.
- The skin has 3 layers.
What is skin made of?
This apparently thin layer covering our body actually consists of 3 different layers, each playing an important role.
1. EPIDERMIS
The most outer layer of your skin, also known as the skin barrier.
Consists of: Skin cells, which are like bricks; and proteins and lipids, which act as the mortar. 90% of epidermis cells are keratinocytes – they’re responsible for skin repair.
Function: acts as a waterproof barrier, that protects your body from UV radiation, heat, parasites and viruses; keeps your body hydrated; produces new skin cells and contains melanin, which determines the color of your skin.
New skin cells are formed in the deepest layer of the epidermis, called the basal layer, and gradually move up to the surface until they become dead cells. The entire process takes about 28 days and then repeats.
2. DERMIS
The middle, and the thickest, layer of skin.
Consists of: Collagen, an elastic tissue, that provides support and structure to your skin. Dermis is also home to vasculature, nerve endings, hair follicles and glands.
Function: protects your body from harm, supports your epidermis, feels different sensations and produces sweat and hair. Supports your skin’s overall structure and keeps it moisturized.
3. HYPODERMIS (Subcutaneous Tissue)
The bottom layer of the skin.
Consists of: fat tissue, blood vessels, fluid called bursa, protein and collagen, hair follicles, lymphatic vessels, white blood cells, nerves and sweat glands.
Function: protects your body from harm, produces D vitamin, stores energy and connects your skin smoothly to your muscles and bones. Without the hypodermis, your skin would rub against tissues and muscules underneath it.
If you have a third-degree burn, this means that the injury has penetrated beyond the first two layers of the skin (epidermis and dermis) and has deeply affected the underlying hypodermis.
How does the skin protect the body?
There are more ways you can probably first think of, how exactly skin protects our bodies.
- By forming a physical barrier, epidermis acts as a shield against pathogens, allergens, toxins and other irritants.
- Melanin protects us from ultraviolet light, that can damage skin cells. When spending time in the sun, our bodies start to produce melanin. This is what makes us tanned. It’s actual function is to absorb harmful rays
- Blood vessels in the dermis protect our body from cold temperature. As skin’s blood vessels constrict, warm blood in the body bypasses the skin and conserves the heat inside the body. Meanwhile skin itself remains cold. In case of hot weather, the vessels dilate, helping to maintain optimal body temperature.
- Microbiota on your skin’s surface is a home to a community of microorganisms, that protect the body by competing with harmful bacteria. They help maintain a healthy balanced skin and prevent the overgrowth of potentially harmful microbes.
- Oils and sweat on your skin also have a protective role. Sweat is actually antimicrobal, so it can kill the growth of bacteria on skin’s surface.
- Sensory receptors play a crucial role in how we experience the world. They allow us to feel sensations like touch, pressure, temperature, and pain. By doing so, they provide us with important information about our surroundings, helping us stay safe and react in potentially hazardous situations.
What are Free Redicals in skin?
Free radicals are often talked about in terms of aging, but what are they really? Let’s try to explain it with a simple parallel. Imagine having a group of mischievous, energetic children playing in a room. They love bouncing around and can occasionally knock things over, causing a bit of chaos. In this analogy the room symbolizes your skin cells, the children represent free radicals and the bouncing and knocking over objects represent the free radicals damaging your skin cells. Just like these lively children, free radicals are highly reactive molecules that are missing a stabilizing electron. This results in skin damage, that can affect DNA, proteins, and cell membranes.
What causes free radicals in the skin? They form as body’s natural byproduct of normal metabolism, but they’re also triggered by smoking, sunlight, pollution and stress. To fight them, you need antioxidants – chemicals that neutralize free radicals. So to reduce free radicals, eat a diet rich in antioxidants (blueberries, broccoli, spinach, carrot etc), limit exposure to UV rays, exercise regularly and try to avoid stress.
The stages of wound healing
Our skin, being the brave front-line defender against all sorts of dangers, is still susceptible to harm. However, it possesses an extraordinary ability to heal itself when injured. Let’s explore how the self-repair process of wound healing works step-by-step.
- Hemostasis aka Blood Clotting: If the injury penetrates deeper layers of the skin, platelets within our blood come together at the wound site to create a blood clot. The clot acts as a temporary seal, preventing further bleeding and providing framework for the healing process that follows.
- Inflammation: When the skin is injured, the body triggers an inflammatory response. Blood vessels in the damaged area constrict to reduce bleeding, followed by vasodilation to increase blood flow. This process results in redness, swelling, and warmth at the injury site. Inflammation helps remove debris, pathogens, and damaged cells, creating an optimal environment for healing.
- Cell Proliferation and Migration: Cells near the wound site start dividing and multiplying to create new tissue. Fibroblasts, specialized cells responsible for collagen production, migrate to the wound area and begin the process of synthesizing new collagen fibers. These fibers provide strength and support to the healing tissue.
- Granulation Tissue Formation: When a wound starts healing, a new kind of tissue forms, which is made up of new blood vessels and connective tissue. You might notice that it looks reddish and bumpy, but it’s actually a good sign, as granulation tissue is an important foundation for the next stages of healing.
- Epithelialization: Epithelial cells at the edges of the wound start to multiply and move, working together to cover the wound and create a fresh layer of skin. This remarkable process, known as epithelialization, plays a vital role in restoring the skin’s protective barrier.
- Remodeling: During the remodeling phase, which can span over several weeks or months, the newly formed collagen fibers undergo reorganization and restructuring. This crucial stage involves strengthening and restructuring the healed tissue, leading to gradual smoothening and reduced visibility of the scar tissue.
During the healing process, several factors play a role in how quickly and effectively the skin repairs itself. These factors include the size and depth of the wound, your overall health, and any underlying medical conditions you may have. It’s crucial to give your skin the care it needs by keeping the wound clean, protecting it from further injury, and creating a healthy environment to aid in healing. Remember, taking care of your skin is essential for optimal recovery.
Skincare: what your skin really needs?
For your skin to be a powerful protector, an expert healer, and to maintain its beauty, softness, and smoothness, it requires its resources. There is even a study confirming that people tend to evaluate a person’s overall health based on their facial skin texture. Those with blemished complexions are perceived as less healthy, while people with smooth skin are viewed as healthier. This evaluation probably happens subconsciously, so we can’t deny the importance of healthy-looking skin.
An average person with no serious skin issues doesn’t really need any extra supplements, fancy expensive lotions or even exfoliators to keep the skin healthy. The most basic must-have list for your skin is:
- Sunscreen. Dermatologists suggest using sunscreen with at least 30 SPF.
- Cleanser. It’s recommended to prefer non-soap cleansers, that are labeled “PH-neutral”, “non-soap”, “soap-free”, “sulfate-free”.
- Moisturizer. This should be chosen based on your skin type, but what you could ideally avoid on your moisturizer are colorings and perfumes; alcohol and too many acids; steroidal ingredients in regular every-day products.
Special care for skin problems
The product list is longer if you have some serious skin issues. In case of eczema and psoriasis, most commonly prescribed medication are steroid creams. But please be careful, because what dermatologists usually don’t tell you, is that using Topical Steroids might have serious consequences, such as Topical Steroid Withdrawal. Read more about it here.
Besides medication (that you might or might not decide to use), there is a lot you can do and use to heal and relieve your symptoms. During hard times your skin needs all the support it can get, whether its supplements, natural remedies, healthy nutrition and lifestyle. This is a wider topic and we’ll cover it separately.
Researchers are constantly making new discoveries about skin – what influences its health and appearance, how to treat different conditions, etc. But there’s still a lot we don’t know and that large complex organ still has secrets to reveal. Don’t forget to observe your skin and be open to learning new things about it. And remember, you are your first doctor – so listen closely to what your body is telling you!
Sources:
https://www.histology.leeds.ac.uk/skin/skin_layers.php
https://my.clevelandclinic.org/health/articles/10978-skin
https://my.clevelandclinic.org/health/body/21902-hypodermis-subcutaneous-tissue
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8481181/
https://medlineplus.gov/ency/imagepages/8912.htm
https://journals.sagepub.com/doi/10.1177/0301006618767258
https://www.nationalgeographic.com/science/article/vitamin-c-retinol-biotin-skin-care-needs