How does dehydration affect your skin?

Dry skin does not always mean you need more water

Body dehydration happens when you lose more fluid than you take in. Dry skin means the outer layer of your skin lacks moisture. The two can overlap, but dry skin alone does not mean your whole body is dehydrated. Low humidity, frequent bathing, soap and certain medicines can also cause dryness. Indoor heating can rob skin of moisture, so a comfortable room can still create extra skincare work.345

What changes can you notice?

Moisture loss can give skin a dull surface and make it less flexible. As dryness becomes more severe, skin can crack, bleed or feel raw. Water touching already painful skin can sting or burn. Breaks in the outer layer also let germs enter, increasing the risk of infection. Fine lines becoming more visible is one sign of moisture loss, rather than the only change to look for.24

Look beyond your skin for signs of body dehydration: thirst, a dry or sticky mouth, darker urine and urinating less than usual. Tiredness and dizziness can occur too. A clinician can assess skin elasticity alongside other signs: dehydrated skin can return slowly after being gently pinched into a fold. Diagnosis also considers symptoms, vital signs and, when needed, blood or urine tests.16

What should you do?

1. 1Replace lost body fluid if you have signs of dehydration. Start with water; small sips or ice chips can help when keeping liquids down is difficult. Electrolytes are minerals that help balance body fluids, and replacing them can matter when you have lost them through illness or heavy sweating.
2. 2Reduce moisture loss during washing. Use lukewarm rather than hot water, replace standard soap with a soap substitute, and choose a short shower rather than a prolonged hot bath.
3. 3Apply moisturizer generously while skin is still damp after bathing. Reapply throughout the day as needed, particularly when skin feels dry or itchy.
4. 4Choose a texture that matches the dryness. Lotion suits mild dryness and hairy areas, cream suits moderate dryness, and ointment suits very dry, scaly areas. Ointments are the most effective at slowing water loss but can feel greasy.

Moisturizer helps hold water in the skin, which is a more useful job than making the bathroom shelf look busy. Ingredients such as glycerine and urea increase the outer layer's ability to hold water. Urea and lactic acid preparations can sting on scratched, cracked or inflamed skin. Stop using a product that causes burning, stinging or a new rash, and seek advice if the reaction persists.57

How long does improvement take?

Dry skin often improves within two weeks when home care is effective. Treating dryness strengthens the outer layer, improves comfort and reduces sensitivity. If dryness continues or worsens, see a dermatologist: medicines, eczema or another medical condition can be involved. A tendency toward dryness can persist, so controlling the trigger matters as well as applying moisturizer.45

When do you need medical help?

Get medical help for yellow crusts, leaking pus, swelling or skin discoloration. Seek immediate medical help for confusion, fainting, no urination, rapid heartbeat or rapid breathing. Severe dehydration needs urgent treatment, sometimes with fluids through a vein. Children, older adults and people taking medicines that increase urination or sweating need particular attention to fluid intake, especially during illness or hot weather.126