What is The Dermis? Functions and Significance

Skin is a complex and vital organ of the body, serving important functions within each of its layers. There are three main layers of the skin: the epidermal, dermal and hypodermal layers. Skin’s middle layer, the dermal layer, is often overlooked as it’s not directly visible to the eye, however its wellbeing serves as a pillar to overall skin health and appearance. Let’s take a closer look at the dermis, and the best ways to keep it healthy.

What is dermis?

Sandwiched between the epidermis and the hypodermis layer, the dermis supports the functions of the other two layers as well as playing a key role in your skin's overall health and structure. Many structures exist in the dermis that impact multiple layers of the skin, including sebaceous and sweat glands, nerve endings, lymphatic vessels, and hair follicles. ¹ Because the dermis hosts these functions, it is the thickest layer of your skin.

Functions of dermis

The dermis has three main functions.

Support the skin’s structure: As the thickest layer of the skin, one of the main roles of the dermis is to structurally support the entire skin. The dermis is made of a network of elastin and collagen
fibers that are bound tightly to provide strength and flexibility in support of the epidermis. ¹ This structure is important for protecting your internal organs from damage.
Provide blood flow for the skin: Both the dermis and epidermis require a large amount of blood flow to support the overall health of the skin. The dermis is full of tiny blood vessels (i.e. capillaries) that transport oxygen and nutrients to the skin's various layers. Dermal blood flow is the primary way the epidermis gets the nutrients needed to continuously regrow.
Support the skin's internal structures: The dermis is where many of the skin's internal structures are located. Functions of the body like sweating, sensation, and producing hair all take place in the dermis. ² These functions require significant resources and necessitate the large amount of blood flow present in the dermis.

Tissue composition of dermis

The dermis supports nearly all of the functions of the skin through its many internal structures. Because of its many roles, the dermis can be split into two distinct layers, the papillary and reticular dermis.

Papillary Dermis

The papillary layer is the top relatively thin layer of the dermis. This layer merges with the bottom of the epidermis and forms a strong bond between the layers. ³ The papillary dermis also contains blood vessels that bring nutrients to the epidermis and aid in thermoregulation. Many nerve endings can be found in the papillary layer including meissner corpuscles, the cells responsible for the sensation of touch.

Reticular Dermis

The reticular layer is much thicker than the papillary dermis layer and is largely responsible for the structural integrity of the dermis. Net like fibers keep the skin durable and elastic. This is also where the internal structures of the skin like sweat glands, and hair follicles can be found. The denser collagen levels in the dermis facilitate the functions of these epithelial structures. ³ Damage to the reticular dermis can often result in more permanent scarring or wrinkling.

Protection of dermis

Even though the dermis is protected by the epidermis from a majority of external aggressors, it is important to bolster the dermis layer in ways that facilitate the health and function of this very important skin layer. Here are three ways to protect the dermis and keep it healthy:

Use sun protection: High levels of UV exposure can cause long term damage to the structure of the dermis leading to visible signs of photoaging and wrinkles. UV exposure can send cells into a state of senescence, prompting the secretion of harmful factors including matrix metalloproteinases (MMPs). These factors break down the collagen and elastin fiber in the dermis leaving the skin depleted of its core structural components. UV damage can also inhibit the ability for new collagen to be produced correctly. The cumulative effects of this damage cause the dermis to lose its strength and leads to sagging, thinning of the skin, and wrinkles. Up to 90% of the visible signs of skin aging can be caused by sun damage. ⁴ Adding sun protection to your daily skin care routine with a peptide sunscreen containing SPF will prevent this damage to your skin. Try to avoid UV exposure during peak UV hours by covering up or staying indoors. Avoiding artificial sources of UV radiation like tanning beds is always a good idea.
Stay hydrated: Maintaining the moisture of our skin prevents the skin from drying out. Staying hydrated by drinking lots of water helps skin cells function optimally. Yet, as we age our skin loses the ability to keep itself hydrated and protected. ⁵ Dry skin is more likely to reveal signs of wrinkling and aging. ⁶ Incorporate a peptide facial moisturizer or a peptide body lotion into your daily skin care routine to keep the dermis healthy. Topical skin care products that promote a strengthened skin barrier can give your skin an extra boost in retaining moisture!
Maintain a balanced diet: Because collagen and elastin in the dermis are constantly renewing themselves, your skin requires a consistent supply of proteins, peptides and amino acids. The skin needs Vitamins A and C, Glycine and many more precursors that cannot be synthesized by the body and must be consumed through foods like fish, meat, dairy, fruit, and legumes. ⁷A lack of any of these nutrients or antioxidants can cause the dermis to become compromised as it struggles to rebuild itself.

Peptide delivery

One important structure of the papillary dermis is the dermal-epidermal junction (DEJ) which binds the epidermis and dermis together both physically and functionally. This channel facilitates molecular transportation from the dermis to the epidermis and vice versa. ⁸To pass through this channel, a molecule must be quite small. Large molecules like collagen are typically unable to pass through the DEJ. However, peptides, the building blocks of proteins, are small enough to use this system to travel from the dermis to the epidermis and also from the epidermis to the dermis. ⁸That’s why topical applications of certain peptides are able to penetrate the epidermis and get to work in the dermal layers!If you’re looking for a simple yet effective skin care regimen to address overall skin and dermal health, consider OneSkin’s Topical Supplements, OS-01 FACE, OS-01 EYE, and OS-01 BODY!The OS-01 peptide has been shown to: ⁹

Increase skin’s epidermal thickness
Increase a key biomarker associated with collagen production, COL1A1
Decrease UV-induced collagen degradation enzyme, MMP3
Increase a key biomarker associated with hyaluronic acid production, HAS2

In lab studies on human skin samples, the scientific team at OneSkin has also confirmed that the OS-01 peptide is able to penetrate to the dermal layer of skin. Recognize that skin is an organ and nurture it like the vital and complex organ that it is with OneSkin.

Key Takeaways:

The dermis is the middle layer of the skin, sandwiched between the epidermis and hypodermis, it plays a vital role in supporting overall skin health and structure.
The dermis, as the skin's thickest layer, plays a multifaceted role by providing structural support, facilitates blood flow, and hosts vital internal structures.
There are two layers of the dermis, the papillary and reticular layers.
Maintaining youthful skin involves daily SPF application and minimizing UV exposure, ensuring hydration, and a balanced diet rich in proteins, peptides, amino acids, vitamins, and antioxidants.

References

Last Updated April 20, 2025

Reviewed by

Alessandra Zonari

PhD, Chief Scientific Officer (CSO) and Co-Founder of OneSkin

Alessandra earned her Master’s degree in stem cell biology, and her PhD in skin regeneration and tissue engineering at the Federal University of Minas Gerais in Brazil in collaboration with the 3B’s Research Group in Portugal. Alessandra did a second post-doctoral at the University of Coimbra in Portugal. She is a co-inventor of three patents and has published 20 peer-reviewed papers in scientific journals.

Diving into Dermis: Functions and Significance