Why Does Eczema Flare in the Summer? The Science Behind Summer Eczema and Natural Support Strategies
- Chelsea Birch, ND, RH (AHG), CBHT
- 2 days ago
- 5 min read
What Is Eczema?
Eczema, also known as atopic dermatitis, is a chronic inflammatory skin condition characterized by dry, itchy, and irritated skin. While it appears on the surface, eczema is much more than a skin-deep issue. It develops through a complex interaction between genetics, immune function, environmental exposures, and the skin barrier itself.
Healthy skin acts as a protective shield, keeping moisture in and irritants out. In individuals with eczema, this barrier is often compromised. As a result, the skin loses water more easily and becomes increasingly vulnerable to allergens, microbes, and environmental triggers that can activate the immune system and drive inflammation.
If you've ever felt frustrated that your eczema worsens during the exact season when everyone else seems to be enjoying the outdoors, you're not alone. While many people associate winter with dry, irritated skin, summer can present its own unique challenges for individuals with eczema.
Why Does Eczema Get Worse in the Summer?
Many people assume eczema should improve during the summer months because of increased sunlight and humidity. In fact, some individuals do notice significant improvement. Research suggests that moderate ultraviolet (UV) exposure can help calm certain inflammatory pathways involved in eczema, which is one reason forms of light therapy are sometimes used therapeutically. Increased humidity can also help the skin retain moisture more effectively.
However, not everyone experiences these benefits. For some individuals, the effects of heat, sweat, allergens, and increased environmental exposures outweigh the benefits of sunshine and humidity, resulting in more frequent or severe flares.
One of the most common triggers is sweat. Although sweating is a natural cooling mechanism, it can be surprisingly irritating to eczema-prone skin. Sweat contains salts and other compounds that may trigger itching when they remain on the skin. As itching increases, scratching often follows, further disrupting the skin barrier and creating a cycle of inflammation that can quickly escalate into a flare.
Heat itself can also contribute to symptoms. Elevated temperatures stimulate mast cells, specialized immune cells that release histamine. Histamine is one of the primary drivers of itching and can leave the skin feeling intensely uncomfortable even before a visible rash develops. Because individuals with eczema often have heightened immune sensitivity, they may react more strongly to heat than those without eczema.
Summer also brings greater exposure to environmental allergens such as grass pollen, tree pollen, mold spores, and air pollutants. These substances don't necessarily need to touch the skin to trigger symptoms. Through complex immune pathways, inhaled allergens can contribute to systemic inflammation and worsen eczema in susceptible individuals.
For some people, time spent in pools can create additional challenges. While swimming can help cool the body and rinse away allergens, chlorine may strip natural oils from the skin and further compromise an already fragile skin barrier. Likewise, excessive sun exposure can trigger inflammation. Although moderate sunlight may have anti-inflammatory effects, sunburn damages the skin barrier and often leads to worsening symptoms in the days that follow.
Even hydration plays a role. During the summer, increased sweating leads to greater fluid loss. Because eczema is fundamentally a barrier disorder, maintaining adequate hydration helps support the skin's ability to retain moisture and function optimally.
The Gut-Skin Connection
Modern research continues to reveal that eczema is not simply a skin condition. The skin and digestive system are deeply interconnected through immune pathways, inflammatory signaling, and the gut microbiome.
Many individuals with eczema exhibit underlying imbalances that may contribute to inflammation, including gut dysbiosis, nutrient deficiencies, food sensitivities, or increased intestinal permeability. When the gut lining becomes irritated or the microbiome becomes disrupted, inflammatory signals can travel throughout the body, influencing skin health and immune function.
This connection is one reason holistic practitioners often look beyond the skin itself when evaluating chronic eczema. While topical therapies can be helpful for symptom relief, addressing factors that contribute to systemic inflammation may offer a more comprehensive path toward long-term improvement.
Can Magnesium Chloride Spray Help Summer Eczema?
One tool that some individuals find helpful during the summer months is topical magnesium chloride spray. Although research specifically examining magnesium chloride spray for eczema is still limited, there are several reasons it may support skin health.
Magnesium plays an important role in hundreds of biochemical processes throughout the body, including those involved in skin repair and immune regulation. The skin barrier relies on a delicate balance of moisture, lipids, and minerals to remain healthy. Because eczema is associated with impaired barrier function, providing magnesium topically may help support the skin's natural healing processes.
Magnesium also appears to influence inflammatory pathways and nervous system regulation. This is particularly relevant for eczema sufferers because itching is not solely a skin phenomenon—it is also driven by nerve signaling. By supporting healthy nervous system function, magnesium may help reduce the intensity of the itch-scratch cycle that perpetuates many eczema flares.
Many people also appreciate magnesium chloride spray after spending time outdoors. Applying it after rinsing away sweat can create a cooling sensation that may help soothe irritated skin. However, because damaged skin can be particularly sensitive, some individuals experience temporary stinging when applying magnesium chloride to inflamed areas. If this occurs, consider diluting the spray with water or applying it to less irritated areas first.
Taking a Holistic Approach
While there is no single solution for eczema, understanding the factors that contribute to summer flares can help you support your skin more effectively. Addressing skin barrier health, supporting hydration, minimizing environmental triggers, regulating inflammation, and evaluating underlying contributors such as gut health and nutrient status can all play an important role.
Rather than viewing eczema solely as a skin condition, a holistic approach recognizes that the skin often reflects what is happening elsewhere in the body. By supporting both the skin and the systems that influence it, many individuals find they can navigate the summer months with fewer flares and healthier, more resilient skin.
If you want a tailored treatment plan addressing your current skin health, past medical history, and comprehensive look at your topicals and supplements, schedule a FREE consultation with me today!
Until next time,
References:
Abdel-Mageed HM, et al. Atopic dermatitis: a comprehensive updated review of pathogenesis and management. 2025.
Kim BE, et al. Significance of Skin Barrier Dysfunction in Atopic Dermatitis. Ann Dermatol. 2018.
Gupta J, Margolis DJ. Filaggrin Gene Mutations with Special Reference to Atopic Dermatitis. Curr Treat Options Allergy. 2020.
Kim Y, et al. Skin Barrier Dysfunction and Filaggrin. Arch Pharm Res. 2021.
Nattkemper LA, et al. Sweat and Itch in Atopic Dermatitis and Healthy Controls. Acta Derm Venereol. 2015.
Murota H. Why Does Sweat Lead to the Development of Itch in Atopic Dermatitis? Exp Dermatol. 2019.
Murota H, et al. Exacerbating Factors of Itch in Atopic Dermatitis. Allergol Int. 2017.
Çetinarslan T, et al. The Immunological and Structural Epidermal Barrier Dysfunction in Atopic Dermatitis. Front Mol Biosci. 2023.
Moosbrugger-Martinz V, et al. Revisiting the Roles of Filaggrin in Atopic Dermatitis. Int J Mol Sci. 2022.
American Academy of Dermatology. Managing Eczema in Summertime.
Mayo Clinic. Atopic Dermatitis (Eczema): Symptoms and Causes.
Disclaimer: This information is generalized and intended for educational purposes only. Due to potential individual contraindications, please see your primary care provider before implementing any strategies in these posts.
