Skin is the biggest organ in the body and a vital defence against invading infections, pollutants and stressors from the outside world. Our faces are the most obvious visible representation of skin health and have a profound effect on us, both from a physical and psychological point of view – after all our faces are the first thing other people notice about us (and we look at them every day in the mirror). So, top to toe, our skin needs lots of TLC and looking after our complexions is vital - not vanity as our mothers/grandmothers tended to cluck when we were younger….

This week sees the publication of a new book called Start With Skincare, written by our hugely respected colleague Alice Hart-Davis, founder of The Tweakments Guide. It’s sub-titled What you really need to know about looking after your skin – and, quite simply, that’s what it is. We’ve been beauty and health editors for over 30 years apiece and, hand on heart, this is the most comprehensive - and crucially most readable - book we’ve ever read. It will cost you just under a tenner (which is amazing) and you will be VERY glad you spent it. It’ll save you a bundle too, by helping you to choose the best skincare for your complexion.

A common question we’re asked is the difference between dry skin and dehydrated skin and what’s the best skincare. It’s not just consumers who are confused: a leading (and expensive) French skincare brand lumps ‘Dry and Dehydrated Skin’ together on its website, with a bunch of products and no guidelines as to which to choose and why… Nul points there.

So we asked Alice to answer this reader’s question:

• Can you explain the difference between dry and dehydrated skin please? I want to choose the most appropriate skincare and I am very confused. My skin seems to veer but is dry with some oily patches (T-zone mainly) and sometimes spots.

Here is Alice’s response… with suggested products at the bottom.

It sounds a ridiculous distinction, like splitting hairs. Something that’s dehydrated is lacking in water, so it’s the same thing as dry. So surely, dehydrated skin IS dry skin - which it is but the way the terms are used in skincare, they mean rather different things. 

DRY SKIN is a skin type. In the same way that some skins are oily, some are just dry – in part down to your genes. Tell tale signs are a rough, flaky or scaly appearance, redness/irritation and a tendency to skin conditions like eczema.

The immediate issue is that the skin barrier - the outer layers of the skin - isn’t doing its job of holding moisture inside the skin effectively. Your skin barrier consists of older, flattened skin cells, sandwiched together with a bunch of lipids (fatty elements in the skin including ceramides, essential fatty acids and cholesterol) to make it waterproof. It’s a vicious circle: when your skin is short on these vital lipids, the barrier doesn’t work so well, which allows more moisture to escape from the skin into the air, which makes it drier…  

What to do – load on products that contain ceramides etc.  Consider a serum with niacinamide, which also helps the barrier by boosting ceramide levels in skin – apply that first and leave it to absorb before adding anything else.

DEHYDRATED SKIN is a skin condition. It means your skin is lacking in moisture and typically looks dull, has lines/wrinkles and is losing ‘bounce-back’ so if you pinch it gently for a few seconds, it tends to sag for a few moments before it goes back. Dehydration may also go with dark circles under your eyes.

The complication comes in that being dehydrated is a problem that can afflict any skin type. Even oily skin can be dehydrated, which I suspect is why you are asking the question.  It sounds contradictory but remember that oil and water are two different elements in the skin: if you try to ‘dry out’ oily skin by washing it with savage oil-reducing, skin-stripping washes, it tends to react by panicking and pumping out more oil to compensate for the resulting dryness. So you get oily/greasy skin with dry patches.

What to do: Dehydrated skin needs moisture/water/hydration. Rather than a creamy moisturiser, you’re better off with a serum containing hyaluronic acid (HA), which will settle into the skin to help it hang onto water. Seal that in place with a moisturiser or a ceramide-rich cream as above. Ceramides shouldn’t upset oily skin.

IN YOUR CASE, it sounds as if you have a classic (and very common) COMBINATION skin, which is a dry skin with an oily T-zone – forehead, nose and chin.

What to do: Start by hydrating with HA serum (or HA and niacinamide) all over, applied to clean dry skin after cleansing. Let that sink in for a ‘sticky minute; then apply a lightweight moisturiser, with ceramides to bolster your skin barrier and seal that layer of HA into place. (Don't forget to put a sun prep over the top – you know why!)

Products to try:

Garden of Wisdom pH-balanced Daily Cleanser/£12 for 120ml

Cetaphil pH-balanced Gentle Cleanser/£14.99 for 473ml

Garden of Wisdom Hyaluronic Acid Serum/£10 for 30ml

Garden of Wisdom Niacinamide Serum/£10 for 30ml

Derma E Acne Rebalancing Cream for sensitive and combo skins/£18.95 for 56g

Garden of Wisdom Daily Hydrator/£10 for 60ml

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