Hydration is the single most universally applicable piece of wellness advice, and also the most consistently ignored. Almost every skin concern, energy complaint, and cognitive difficulty has dehydration as a contributing factor.

The human body is approximately 60% water by weight. The brain is closer to 75%. A reduction of just 1% in total body water is sufficient to produce measurable decrements in cognitive performance, mood, and perceived energy. A reduction of 2% produces detectable impairment in physical performance. Most people are walking around in a state of mild, chronic dehydration and have normalised the way it feels.

What dehydration does to skin

The skin is the last organ to receive water when the body is in deficit — it is considered non-essential by the body’s distribution hierarchy. This means that by the time your skin shows signs of dehydration (fine lines that appear when the skin is pressed together, a dull or tight complexion, exaggerated pores), you are already significantly under-hydrated systemically.

Dehydrated skin has a compromised barrier function — it is less able to regulate moisture loss, more reactive to environmental stressors, and more susceptible to sensitisation. No topical moisturiser can fully compensate for systemic dehydration.

Beyond water: the minerals that matter

Pure water alone is not the most effective hydration vehicle. Water transport into and across cells is regulated by electrolytes — sodium, potassium, magnesium, and chloride. Drinking large quantities of mineral-free water without adequate electrolyte intake can actually flush electrolytes from the body, worsening cellular hydration despite high fluid intake.

A pinch of good sea salt in water, coconut water, mineral-rich broths, and magnesium-rich foods (dark leafy greens, seeds, dark chocolate) all support electrolyte balance and therefore cellular hydration more effectively than plain water alone.

Hydrating foods worth including

Cucumber: 96% water, plus silica — a trace mineral that supports collagen production.
Watermelon: 92% water, plus lycopene — a carotenoid with photoprotective properties.
Celery: 95% water, plus natural sodium and potassium.
Fatty fish: Omega-3 fatty acids support the skin’s lipid barrier, reducing transepidermal water loss.
Bone broth: Collagen, glycine, and trace minerals — a traditional food with genuine skin-supporting properties.

Topical hydration: what actually works

Hyaluronic acid is the most effective humectant available — a molecule capable of holding up to 1,000 times its own weight in water. Applied to damp skin and sealed immediately with a moisturiser or facial oil, it draws moisture from the air and the deeper layers of the dermis to the surface.

Without the occlusive seal, however, hyaluronic acid applied to dry skin in a dry environment can have the opposite effect — drawing moisture from the dermis to the surface and then losing it to the air. The sequence matters: humectant first, then seal.