Skin: The Largest Organ of The Human Body
Which is the largest organ of the human body is? The brain? Heart? Liver? Intestines? It’s none of these.
The largest organ is the skin. Yes, the skin is an organ and one of the most complex!
Alongside its role in protecting us from many different environmental challenges, it is an extremely active structure.
The skin is both the source and target of several hormones, has its own immune system, is our largest sensory organ, and so on. Without this remarkable organ, human life as we know it would not be possible.
Human skin is really amazing. Even at its thickest point, our skin is only a few millimeters thick. But it is our largest and heaviest organ, making up about one seventh of our body weight.
Depending on your height and body mass, the skin weighs between 7.5 and 22 pounds) and has a surface area of 1.5 to 2 square meters. On the average human, the skin weighs about 8 to 9 pounds, covers an area of over 22 square feet, and has 300 million skin cells (19 million per square inch).
The skin contains over 11 miles of blood vessels and 45 miles of nerve cells.
Functions of the Skin
Every single day of our lives, our skin acts as a shield between us and the outside world.
Our skin is our first line of defense against the outdoor elements like air pollution as well as other chemicals that touch our skin in laundry detergents, personal care products, and even swimming pools.
Some functions of the skin include:
- protects against pathogens (germs)
- prevents excessive water loss from our body
- insulates us from heat and cold
- aids in temperature regulation
- provides a protective barrier against mechanical, thermal and physical injury and hazardous substances
- prevents loss of moisture
- produces vitamin D
- acts as a sensory organ (touch, heat, cold and pain)
- provides an airtight, watertight and flexible barrier between the outside world and the highly regulated systems inside the body
And along with all of those awesome things it does, our skin is so sensitive that we can feel the weight of a fly.
The Skin Has Three Main Layers
These three layers are well defined but work together to allow the skin to function effectively.
Epidermis: This is the outermost layer of your skin.
The epidermis is the thinnest layer of skin. It protects you from the outside world by acting as a barrier against foreign substances. The epidermis prevents bacteria and viruses from entering the deeper layers of the skin.
The epidermis continually makes new skin cells needed to replace the approximately 30,000 to 40,000 old skin cells that your body sheds every day.
Since new skin cells last for about a month before they fall off, you actually have new skin about every 30 days. The epidermis also contains melanin, the pigment that gives skin its color.
The outermost parts of the epidermis consist of 18 to 30 thin layers of dead cells which prevent water loss from the skin.
Dermis: The middle layer of skin, the dermis, lies beneath the epidermis, makes up 90% of skin’s thickness and has many functions.
- Contains collagen and elastin for skin strength and flexibility
- Contains the roots of hair follicles
- Contains the nerves that help you feel pain and tell you when something is hot, itchy or super soft.
- Contains oil glands that help keep the skin soft and smooth. Contains
- Contains the sweat glands which help regulate your body temperature.
- Contains blood vessels that provide nutrients to the epidermis, keeping the skin layers healthy.
Hypodermis (Subcutaneous Layer): The bottom fatty layer of skin. The thickness of this layer varies dramatically depending on the site and the body shape and weight of the person. This fatty layer:
- cushions the body from external trauma which helps protect muscles and bones from injuries
- insulates from the cold
- stores energy (fat)
- contains connective tissue that connects layers of skin to muscles and bones.
- contains larger blood vessels and nerves and helps regulate body and skin temperature.
What Is The Skin Barrier?
While the skin is made up of the three main layers described above, each of these layers has several sublayers, most of which perform unique, specialized functions. For any discussion about skin care, the focus is really on the epidermis.
The epidermis is actually subdivided into five layers. The outermost layer, called the stratum corneum, functions as the physical protective barrier.
The structure of the stratum corneum is like a brick wall in which the actual skin cells are the bricks and everything else is the cement that fills in between the bricks and holds it all together.
Since this "cement" is made up of fats and other essential nutrients it referred to as the "lipid layer or lipid barrier" and prevents water from easily entering or leaving your body. As we get older, our lipids naturally decrease, which is why skin tends to get drier as we age.
Your "skin barrier" is the outer surface of your skin made up of the Lipid Layer plus the Acid Mantle and the Microbiome.
The Acid Mantle: This is a very thin, slightly acidic, moist layer caused by normal secretions from sweat glands and sebaceous (oil) glands, dead skin cells, the breakdown of fatty acids by good bacteria that live on our skin and other skin secretions. The acidic pH allows beneficial bacteria to live happily on our skin while it deters bad bacteria.
The Microbiome: It is estimated that our skin is home to about 1 trillion beneficial microorganisms (skin flora) which make up a tiny ecosystem called the skin microbiome. Although science is just starting to understand everything the skin microbiome does, we know that it is an essential part of the body’s immune system. Similar to those in our gut, our skin microorganisms have key roles in the protection against infection.
Does Our Skin Really Absorb Everything We Put On It?
One of the ongoing controversies is the effect of synthetic chemicals in personal care products on our skin and our bodies.
To better understand the controversy, let’s talk about the concepts of skin penetration and skin absorption. While these two terms are often used interchangeably that is just not correct.
- If a chemical or substance is applied to the skin, it may only penetrate the first of the three layers of skin. With penetration, the systems of the body are not affected.
- If a chemical or substance is absorbed through the skin, it goes through all three skin layers, reaches the bloodstream and can affect internal body systems.
- For example, olive oil only penetrates the skin, while the drugs in a transdermal nicotine patch are absorbed.
When choosing skincare products both concepts are important. While many chemicals can penetrate into the deepest levels of the skin, many are too large to be absorbed directly into the bloodstream or their absorption rates are very slow.
So what about synthetic chemicals in soap, detergents, body creams, and other such products? Do they merely penetrate, or are they absorbed?
And, if absorbed, what is the long-term effect on our bodies? At this time there is no definitive answer.
We don’t agree with the scare tactics used by some companies concerning skincare ingredients. I have read comments like “up to 75% of what you put on your skin is absorbed into your bloodstream."
It would be great if I could absorb enough calcium into these old bones by simply taking a bath in milk--but it can't happen--the calcium molecules are too large.
However, there have been studies revealing that some synthetic chemicals in personal care products, like phthalates and parabens, show up in blood and urine tests, which means they are absorbed.
There is not enough research on the skin absorption rates of many chemicals nor on the effects of years of daily use of these chemicals.
The problem is that chemicals come in different sizes and have different absorption rates over time. To complicate that even further, we, as human beings are not all the same. Your precise chemical makeup is not exactly the same as everyone else which presents a real challenge for accurate research on absorption rates or the long-term effects of chemicals and their components on "every" body.
Whether the claims about links to serious health issues are true or not, it is that “unknown” factor that always worries me the most.
So, Why Are We Discussing Skin?
Chagrin Valley Soap & Salve manufactures natural organic soap, shampoo, and other personal care products. Naturally, we care about how our products interact with our largest organic.
Our Company was created because of a sincere concern about the chemicals present in personal care products and the potential adverse effects of these chemicals on us, our children, and our planet.
We believe that we do not need synthetic chemicals to have effective soap, skin, and hair care products
It's all about ingredients! Our products have always, and will always, contain nothing but natural ingredients.
There is nothing artificial, nothing synthetic, no GMOs, just wholesome natural ingredients you can trust.