Three things going on at once
Eczema (atopic dermatitis) isn't one simple thing — it's a combination of a skin barrier that doesn't seal well, genes that set that up, and an immune system that overreacts. They feed each other. Here's each piece.
1. A leaky skin barrier
Healthy skin is like a brick wall — cells (bricks) held together by fats (mortar) that keep water in and irritants out. In eczema, that wall is leaky. Water escapes (so the skin is dry), and irritants, allergens, and germs get in more easily (so it inflames and itches). Fix-and-protect that barrier and you're treating the root of the problem — which is exactly why moisturizing isn't optional, it's the therapy.
2. Genes — especially filaggrin
The most well-established genetic factor is a change in a gene called filaggrin (FLG) — the protein that helps build that brick-and-mortar barrier and keeps skin hydrated. Many children with eczema make less working filaggrin, so their barrier is weaker from birth. This is inherited, which is why eczema, asthma, and hay fever often run in families. You didn't cause it; your child was born with a skin barrier that needs extra help.
3. An over-eager immune system
Once irritants and allergens slip through the leaky barrier, the immune system reacts — and in eczema it tends to overreact, driving inflammation and that maddening itch. That inflammation damages the barrier further, which lets more in, which fuels more reaction. That's the loop behind a flare — and why newer targeted treatments for severe cases aim at specific immune signals.
What causes flares (vs. what causes eczema)
Worth separating: the underlying cause is the barrier-gene-immune combination above. Flares are set off on top of that by triggers — dryness, heat, sweat, irritants, sometimes stress or (less often than people think) foods. Your child has eczema because of the barrier; it flares because of triggers. Managing both is the game.
What is not the cause: it's not poor hygiene, not something you ate or fed, not being ‘dirty,’ and not a weak or broken immune system in the usual sense — it's an immune system that's over-reactive, not deficient. Letting go of the guilt isn't just kind; it's accurate.
Care for the cause you can actually reach
You can't change the genes — but you can support the barrier every day. Ollowen keeps that daily care on track and shows you what helps, turning the science into a routine you can see working.
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Sources
- Palmer CN, et al. Filaggrin in atopic dermatitis. J Allergy Clin Immunol.
- Review. The etiopathogenesis of atopic dermatitis: barrier disruption, immunological derangement, and pruritus.
- National Eczema Association. Causes and triggers of eczema.
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