A Functional Approach to Skin Conditions: Eczema and Psoriasis

In Functional Medicine a diagnosis serves as the beginning not the end of the detective process. Continuing to ask the question “why” instead of focusing on the what, allows us to get to the root cause for each individual.

While eczema and psoriasis present differently, they share some of the following commonalities: barrier disruption, inflammation, dysbiosis, leaky gut, food triggers, and nutritional deficiencies.

Traditional dermatological approaches target inflammation topically with steroids or internally with immune suppressing agents. While these can be effective and appear to resolve the area of inflamed skin there is often recurrence elsewhere or rebound flares when these medications are discontinued. Our goal in functional medicine is to explore what is causing an overactive immune response and take a holistic approach to address all of the body systems involved. Let’s walk through a functional approach to addressing these common skin conditions.

Defining Eczema & Psoriasis

What is Eczema? 

Eczema, also known as atopic dermatitis, is the most common inflammatory skin condition in the US. It is a disease of barrier dysfunction and inflammation both externally and internally. Individuals may have a genetic predisposition that leads to an impaired skin barrier. Often people with eczema also suffer from allergies and asthma, this is referred to as the atopic triad.

What is Psoriasis?

Psoriasis is an autoimmune condition that accelerates the life cycle of skin cells, causing cells to build up rapidly on the surface of the skin. The extra skin cells form scales and red patches that are itchy and sometimes painful. There are many conditions that coexist with psoriasis including cardiovascular disease, metabolic syndrome, type 2 diabetes, depression, and IBD. These comorbidities share the common thread of inflammation which contributes to their pathologies.

What Could Be the Root Cause?

• Microbiome Dysbiosis: Individuals with eczema and psoriasis often have an overgrowth of problematic bacteria and yeast and an undergrowth of beneficial organisms like lactobacillus and bifidobacteria. Often, we see an overgrowth of staph aureus in patients with eczema and streptococcus in patients with psoriasis. Candida overgrowth is common in both groups and can be caused by a diet high in sugar, refined carbs, processed foods, and low in fiber.

• Leaky gut: Also referred to as increased intestinal permeability, is another driver of inflammation for many individuals with eczema and psoriasis. 80% of our immune system surrounds our gut and is constantly surveying it’s environment. When our gut lining is impaired larger food particles and organisms can interact with the immune system. These larger particles look foreign and in order to protect us from this potential invader are immune system mounts an inflammatory response.

• Food Triggers: Eggs, dairy, and wheat are the most common foods that trigger eczema and psoriasis. Some individuals with eczema also react to high histamine foods like tomatoes, alcohol, citrus, and vinegar. Ruling out IgE food allergies is also a reasonable area to explore in patients with eczema.

• Nutritional Deficiencies: The standard American diet is low in essential fatty acids, antioxidants, vitamins, minerals, and fiber. Low vitamin D is also common in individuals with eczema and psoriasis and critical for a healthy immune response.

• Environmental Factors: Toxins, pollutants, mold, and allergen exposure can all contribute to an overactive immune system.
• Lifestyle: High Stress, poor sleep, and sedentary living contribute to the inflammatory cascade

What are the Treatment Approaches for Skin Conditions?

• Elimination Diet: identifies triggers and reduce inflammation. This is followed by implementation of an anti-inflammatory diet that is rich in whole foods, balances blood sugar, and is high in protein, fiber, and healthy fats. It is also important to ensure a diverse phytonutrient diet to promote a balanced and resilient microbiome. You can learn more about the elimination diet here.
• Gut Healing Protocol: This is guided by the 5R Functional Medicine Approach: Remove, Replace, Repair, Re-inoculate, and Re-balance.
• Address Lifestyle Factors: Improve Resilience to Stress, ensure a minimum of 7 hours of sleep per night, increase exercise and regular movement. UV light exposure and time spent outdoors has also shown to be therapeutic for patients with psoriasis.
• Supplements: Omega 3s, Vitamin A, Zinc, Vitamin D, Vitamin E, etc.

The Role of Diagnostic Testing

Functional Medicine often employs advanced diagnostic testing to delve into the root causes of skin conditions, offering personalized treatment strategies. These might include:

• Food Sensitivity and Allergy Testing: To identify specific triggers.
• Gut Microbiome Analysis: Understanding the skin-gut connection is critical when addressing the root cause of dermatologic conditions. Genova’s GI Effects^® is a comprehensive assessment of your complete gut health profile.
• SIBO Breath Test: It may be important to assess for an overgrowth of bacteria in the small intestine that could be driving the immune response.

How Cold Weather Affects the Skin

As the weather turns colder, many individuals notice changes in their skin health. The drop in temperature and humidity during winter months can strip the skin of its natural moisture, leading to dryness, irritation, and flare-ups of inflammatory skin conditions such as eczema and psoriasis. These effects are not merely cosmetic—they reflect the way environmental stressors interact with the skin barrier and immune system.

Research has shown that colder, drier climates can significantly disrupt skin barrier integrity, making the skin more vulnerable to transepidermal water loss and microbial imbalance. This weakening of the skin’s protective layer increases susceptibility to irritation, itchiness, and inflammation. In individuals with atopic dermatitis, these seasonal shifts can worsen existing inflammation and compromise healing.

Climatic factors, including lower outdoor humidity and temperature fluctuations, were associated with higher rates of childhood eczema. More recent cohort research from England further supports this connection, demonstrating that abrupt temperature changes—particularly cold, dry air—can trigger eczema flares and exacerbate symptoms.

Even for those who do not struggle with eczema or psoriasis, winter can still bring noticeable skin changes. Reduced humidity, indoor heating, and cold wind exposure can deplete the skin’s natural lipids and moisture barrier, resulting in dryness, flaking, and sensitivity. This is often referred to as “winter xerosis,” a common seasonal condition that can make the skin feel tight or rough. Preventive care—such as maintaining hydration, using gentle cleansers, and applying moisturizers rich in ceramides and fatty acids—can help preserve barrier integrity and comfort throughout the colder months.

Managing Eczema and Psoriasis in the Winter

For those managing eczema or psoriasis, proactive skin care is essential during the winter months. Supportive strategies may include:

• Humidifying indoor air to maintain moisture balance.
• Using ceramide-rich moisturizers immediately after bathing to lock in hydration.
• Avoiding overly hot showers, which can strip oils from the skin.
• Wearing soft, breathable fabrics to reduce irritation.
• Supporting internal hydration and nutrition, as omega-3 fatty acids and antioxidants aid in skin barrier repair.

In Functional Medicine, these environmental influences are viewed as another piece of the puzzle. By addressing both internal and external triggers—nutritional, microbial, hormonal, and climatic—we can create resilience in the skin barrier and reduce the frequency and severity of flare-ups, even through the challenges of the colder season.

Final Thoughts

Eczema and Psoriasis are complex conditions that require a multifactorial approach. As a Functional Medicine Physician, my job is to guide patients on their journey of healing, addressing the root causes, and empower them with the tools and knowledge to achieve and maintain healthy skin and a healthy body.

Our skin is a reflection of our internal health. By caring for our bodies from the inside out, we can achieve lasting health and vibrant skin.

Resources:

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Chan, J., MacNeill, S., Stuart, B., Lo, Y., Roberts, A., Mitchell, D., & Ridd, M. (2023). Do temperature changes cause eczema flares? An English cohort study.. Clinical and experimental dermatology. https://doi.org/10.1093/ced/llad147.