The Science Behind the Layers of your Skin

 

We might moisturise, exfoliate, and protect it from the sun, but how much do we really know about our skin?

 

Yes, it holds us together, but it also plays a vital role in regulating our body temperature, preventing water loss, and defending our immune systems.

 

In this guide, we will explore the fascinating science behind the three main layers of skin, their functions, and practical ways you can keep them healthy.

 

What is the skin?

 

Skin is the soft, flexible outer layer that covers your body, serving as a shield that protects you. It plays a vital role in many bodily processes, quietly ticking along in the background, even when it may not be on your daily radar.

 

In essence, the skin is not just a barrier; it is dynamic and can reflect our overall health and well-being.

 

Is skin an organ?

 

The skin is the largest organ of the body, covering a surface area of 15-20 square feet. For something to be defined as an organ, it must meet specific criteria – a structure consisting of tissues and cells, which perform a specific function. While made up of tissues and skin cells, there is a lot more that goes into it – including water, protein, fats, and minerals.

 

What are the 3 main layers of skin?

 

1. The epidermis – This is the layer of skin we can see. Did you know that the thickness of our epidermis varies depending on where it is located? For example, the epidermis on the soles of our feet is thickest, whereas the epidermis around our eyes is thinner and more delicate. The epidermis is in a constant state of renewal, with fresh skin cells emerging from the deeper skin layers and migrating to the surface, where they create a protective barrier.
2. The dermis – This is the thickest layer of skin. Like the foundation supports a house, the dermis provides structure and stability to the skin, ensuring it remains resilient and strong. The dermis is host to a rich supply of blood vessels, and it has many nerves that make us feel touch, pressure, pain, and temperature. The dermis is a strong layer that is also very stretchy. If this skin layer gets stretched too much (e.g. during pregnancy), this can cause stretch marks to form.
3. The subcutaneous layer – This is the cushioning layer of fat and connective tissue that lies between the dermis and the underlying muscles. Think of it as your body's built-in shock absorber, not only guarding against injuries but also giving your internal organs a comfy place to chill.

 

What is the main function of skin?

 

The skin acts as a barrier to environmental threats that we face daily. From pollutants, harmful UV rays, chemicals, and bacteria – the skin helps to block out most of these. By maintaining this barrier, the skin not only keeps us safe but also allows our bodies to thrive in a complex and often challenging world. The skin also provides a myriad of other crucial functions, including:

• Serving as a water-resistant barrier
• Guarding against injury
• Producing vitamin D and hormones
• Cultivating its own microbiome, with a healthy balance of different fungi, bacteria, yeasts, and viruses.

 

Why is skin important?

 

Healthy skin can support your confidence, while changes in the skin’s appearance may signal underlying health problems, prompting you to pay attention to your body. With its ability to heal and regenerate, skin showcases the body’s resilience.

 

And let’s not ignore the social aspect, your skin is a canvas for self-expression. It can influence how you feel about yourself and how others see you. Your skin can be the ultimate accessory, making it crucial to treat it right.

 

Does skin regulate body temperature?

 

The skin is your very own thermostat, keeping your body regulated at a breezy 37°C. It keeps you cool when you are warm, with glands producing sweat, which evaporates and cools you down. Blood vessels also dilate, allowing more blood flow to the surface of the skin, releasing heat.

 

The hair on the skin also plays an important role in regulating body temperature. You may have noticed that your hairs stand up on end when you are cold, and there is a reason for this. These hairs are trapping a thick layer of air above the skin, insulating your body. While when it is too warm, the hairs will lie flat, allowing more heat to be lost to the surrounding air. Who knew your body had its own built-in climate control system?

 

What causes skin to age?

 

Smoking - is known to cause premature skin ageing, delayed wound healing, and increased risk of skin infections. It does this by decreasing blood capillary flow to the skin, which prevents oxygen and nutrients reaching the skin. Tobacco also causes oxidative stress, which can induce signs of skin ageing.

 

Lack of quality sleep - can speed up skin ageing. Those who enjoy better sleep quality tend to bounce back from UV exposure like champions. There lies some truth in the term ‘beauty sleep’, research reveals those that catch more quality Z’s are more likely to think of themselves as better looking.

 

Skin-care choices - It’s not all about targeting your skin from the inside out, poor skin-care choices can leave your skin looking dull and prone to ageing faster. Leaving your makeup on, using harsh topical treatments, or not looking after your skin with topical treatments, can all be detrimental to your skin health.

 

Sun damage can cause your skin to age fast, as well as increase your risk for skin cancer. A study found that a staggering 80% of visible signs of ageing can be traced back those sun-soaked days.

 

Want to know more about the common causes of skin ageing? Check out our blog on lifestyle factors that cause skin ageing.

 

How to keep your skin healthy?

 

While extrinsic factors, like genetics, age, and hormones, can all affect the skin, getting beautiful skin from within, can include many modifiable factors.

 

Exercise

 

Working out supports blood circulation, leading to more nourished skin cells, as well as supporting with the removal of toxins. Plus, exercise reduces stress levels, giving your skin a healthier, more vibrant appearance. Want to learn more? Check out our blog on exercise for healthy skin.

 

Hydration

 

The skin is approximately 30% water; therefore, it should come as no surprise that being adequately hydrated can be useful to support its’ function. While, hydration will not prevent signs of ageing, it may support with skin turgor in those who are dehydrated.

 

Nutrition

 

Incorporating omega-3 rich foods into your diet, like oily fish, can combat inflammation and support with inflammatory skin conditions, like acne, psoriasis, and eczema. Oily fish, like salmon, krill, and lobster are also rich sources of astaxanthin, a powerful antioxidant that can support the skin. Consuming a balanced and nutritious diet is key to healthy skin. Vitamin A can contribute to the maintenance of normal skin, so make sure you are including lots of carrots, fish and cheese in your diet. You may also wish to consider supercharging your diet with superfoods for skin.

 

Skincare

 

Getting a solid skincare routine in place can help you tackle those pesky skin concerns with ease. Research suggests this should focus on a three-step approach which includes protection, renewal and activation. This may look different for everyone, but sun protection should be at the forefront of your routine, especially during the summer months.

 

Mind-skin connection

 

High amounts of stress can take a toll on your skin, activating pro-inflammatory skin cells. From faster ageing, to aggravating existing skin conditions, stress and anxiety can play a big role in being your skin’s worse enemy. Improve your stress levels by incorporating mindfulness activities into your daily routine. Wanting some inspiration about what this could look like? Try out these relaxation tips while staying at home.

 

Supplementation

 

Supplements for the skin can be useful for some people, especially if you are looking to enhance your skincare routine from the inside out, giving your skin cells the nutrients they favour.

• Collagen - Collagen is the most abundant protein in the skin. Type I collagen peptide profiles are the ones you want to look out when supporting with skin ageing. Our Collagen Beauty range provide both type I (found in the hair, skin and nails) and type III (found in the muscles, arteries and connective tissues). In fact, clinical studies have shown that taking 2.5g of VERISOL® bioactive collagen can reduce the appearance of wrinkles up to 50%.
• Anthocyanidins – These plant pigments give the deep colour to fruits and berries. Research suggests these compounds can prevent the destruction of collagen. Besides, increasing your dietary intake, you may also wish to consider a high strength anthocyanidin formula, like our Colladeen Original or Colladeen Visage.
• Vitamin C - To support with collagen formation, vitamin C for skin is an essential component. You can find vitamin C in citrus fruits and green leafy vegetables, alternatively vitamin C supplements can be useful for some people.
• Vitamin D - Many of us within the UK are deficient in vitamin D. But did you know that low levels of vitamin D can aggravate common skin concerns, like acne? Taking a vitamin D supplement, especially during the autumn and winter months, may give your skin the support it needs.
• Multivitamin - A general multivitamin can reduce the risk for micronutrient deficiencies, as well as provide vitamins and minerals to support with skin health, like vitamin A, some B vitamins, and zinc. Our Multi-Max Hair, Skin and Nails may be suitable for some people, especially those under 50 years, to support with skin health. If you are over 50 years old, you may wish to consider our Multi-Max Hair, Skin and Nails Gummies.

 

Final thoughts

 

The skin is the largest and one of the most important organs of the body. Therefore, looking after it is as important as the inside of your body. Whether you are looking to reduce the signs of ageing, have an inflammatory skin condition, or are just wanting that glowy look, taking care of your skin with nutrition and lifestyle factors are the way to go.

 

Exercising, good nutrition, reducing stress, and supplementation can all help you on the path to healthy skin. Explore more ways to protect and care for your skin over on our dedicated health blog, or contact our expert Nutrition Advice team for free and confidential support.

 

References

 

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