46 skincare facts we learned from dermatologist Dr. Sam Bunting: how to know if your routine is working, whether collagen is worth it and the skincare mistake she sees every day

I don’t recommend them. Collagen is broken down into amino acids when you digest it, and the evidence that supplements improve skin is weak. Eat plenty of good-quality protein, such as fish, eggs, meat, dairy or pulses, and stick to the proven measures: daily sunscreen and a retinoid.

If you care about preventing premature ageing, a daily broad-spectrum sunscreen is a necessity, even in the UK, because ageing UVA rays are present all year round and come through glass.

As for vitamin D; your skin makes vitamin D from UVB rays, and from October to March there isn’t enough UVB in the UK for your skin to make what it needs, so I'd always recommend taking a supplement over those months.

When almost everything stings, a damaged barrier is the most likely culprit, especially if you’ve been using lots of actives or changing products often.

Rosacea and eczema can cause it too. The good news is that your skin barrier can recover. Strip your routine right back for four to six weeks to just two products: if you need a recommendation, I'd suggest Flawless Cleanser, £20, which cleans without stripping, and Flawless Moisturiser Intense, £36, to rebuild and protect the barrier.

Add a daily SPF once things are improving and then reintroduce your other products one at a time. Consider whether you need to cut back on what you were using. If your skin still stings after that, see your GP or a dermatologist to check for an underlying condition.

Used sensibly, AHAs are fine, so there's no need to throw yours out. The problems start when people use them every day or layer them with other strong actives. Watch for signs your barrier is struggling: stinging when you apply products, tightness, redness or a shiny, tight look to the skin. If that sounds familiar, take a break and focus on a gentle cleanser and a good moisturiser until your skin settles. Two or three times a week is plenty for most people and always wear SPF the next morning.

Painful spots along the chin and jaw that keep recurring at the same time each month are a common finding in adult female acne. The good news is it doesn't necessarily mean there's anything wrong with your hormones. A simple routine with azelaic acid combined with a retinoid helps to keep breakouts under control over time. If they keep coming back, see your GP, as treatments such as certain contraceptive pills or spironolactone can make a real difference. It's also worth a check-up if you do have irregular periods or excess hair growth, as these can point to PCOS.

LED masks can help a little with issues such as fine lines but keep expectations modest. Price isn’t everything. Choose a brand that lists its wavelengths and shares clinical data. We don’t yet know the ideal dose, so stick to the instructions, usually 10 to 20 minutes a few times a week.

Doing too much. I see it every single day in clinic: people layering five or six actives, switching products every few weeks and chasing whatever's trending online. Their skin ends up red, sensitised and breaking out, and then they buy even more products to fix it. That frustration is exactly why I started making videos back in 2015, created Dr Sam's in 2018 and wrote my book, Flawless, published last month.

Most skin really only needs four steps: a single cleanse, treat your main concern with the right active, moisturise to support your skin barrier and protect with SPF every morning. Pick a routine that suits your skin, stick with it for at least three months, and let it do its job. Consistency beats novelty every time.

It really depends on what the product is meant to do. You’ll know within a couple of weeks whether a cleanser, moisturiser or sunscreen suits you, because it’s all about how your skin feels. Actives need much longer. Give anything for breakouts or redness at least eight to 12 weeks, pigmentation around 12 weeks, and a retinoid for fine lines a good three to six months. A little dryness or the odd spot in the first few weeks of a retinoid is normal while your skin adjusts. Persistent burning, a rash or swelling is different, and that’s your cue to stop. Change one thing at a time so you know exactly what’s working.

Perimenopause can really throw your skin into turmoil. As oestrogen drops, your skin makes less collagen and the barrier gets weaker. That’s why so many women suddenly find themselves dealing with dryness, sensitivity, breakouts, redness and pigmentation all at the same time.

Starting again with a simpler routine is a really good idea. Keep it to a gentle cleanser, a rich barrier-repairing moisturiser and an SPF every morning, then add just one active. I love azelaic acid here because it tackles breakouts, redness and pigment in one go.

Once things calm down, you can bring in a retinoid a couple of nights a week to help with collagen. And if you’re thinking about HRT, have a chat with your GP, because it can do wonders for your skin as well.

I’m so sorry to hear this. It sounds like perhaps you’re having chemotherapy? The most important thing right now is keeping your skin barrier healthy, so stick to gentle cleansing, a barrier-supporting moisturiser and a daily sunscreen. If the Mixa ointment is soothing your face, it’s absolutely fine to keep using it.

Once your skin feels calmer, a niacinamide serum might help deliver some extra radiance, which can be a real lift for morale, but do check with your oncology team before adding anything new. Wishing you all the very best with your treatment.

Either can work. What matters is having the right active for your skin concern, in a routine simple enough to stick to. Using one brand has its advantages: the products are designed to work together, which lowers the risk of doubling up on actives and irritating your skin. If you do mix and match, keep it to four steps - Cleanse, Activate, Hydrate, Protect - and check you’re not layering several strong actives at once. Introduce one new product at a time so you can tell what’s working. The biggest mistake I see is constantly switching. Give a routine at least 12 weeks before you judge it.

Retinoids have the strongest evidence of any topical ingredient for treating signs of ageing, and I’ve prescribed them for two decades.

Retinol is one member of that family. It acts more gently and slowly than a prescription retinoid, and the results depend a lot on the formula and the strength. I don’t recommend it for everyone. If you have rosacea or very reactive skin, or you’re pregnant or trying to be, a retinoid is the wrong place to start, and azelaic acid is often the better first active because it treats redness, breakouts and uneven tone with much less irritation.

My approach is to match the active to your main skin concern, start with a low strength two or three nights a week, and build up once your skin is tolerant. Flawless Nightly Serum is a great retinoid for beginners if you need a recommendation.

A gentle cleanser, one active chosen for your main concern, and a daily broad-spectrum sunscreen. If I had to pick my two favourite actives, I'd say azelaic acid, which suits redness, breakouts and uneven tone or a retinoid, which helps with fine lines, prevents clogged pores and future breakouts. Sunscreen is the one I’d never skip - up to 80% of visible ageing is down to UV exposure.

Perioral dermatitis is one of the most common things I see, especially in people who are always switching up their skincare, which is why it’s rife in people who work in the beauty industry.

Look for tiny red bumps around the mouth with a thin clear band of unaffected skin along the lip line. Toothpaste and steroid nasal sprays can trigger it too. Start with a full product detox: a simple cleanser and a barrier-repairing moisturiser. If it doesn’t settle, see your GP. I cover it in detail in my book Flawless because getting the diagnosis right really matters.

Dark circles usually come down to one of three things: pigment, thin skin showing the blood vessels underneath, or hollowing that casts a shadow. Lack of sleep makes all of them look worse, but genetics and anatomy are often the real drivers.

For pigment, a gentle eye product with niacinamide, vitamin C or a low-strength retinoid helps over time, along with daily SPF close to the lash line. This works because protecting your collagen levels preserves skin thickness, I recommend Flawless Nightly Eye Serum, £40, which combines all three actives in one product.

If hay fever or eczema has you rubbing your eyes, getting that under control makes a big difference. Hollowing is structural, so no cream will fix it, and that’s where an in-clinic assessment is worth it. Work out which type you have first, then treat it properly.

Melasma is a chronic condition that causes symmetrical pigmentation in patches, typically on the forehead, cheekbones and upper lip - the goal here is long-term control.

Sun protection is non-negotiable: wear a high-factor sunscreen every day, ideally a tinted one, because the iron oxides also block the visible light that drives pigment. Heat and hormones play a big part too, so keep hot yoga and saunas to a minimum.

For treatment, azelaic acid is my go-to, and it pairs well with niacinamide and a retinoid. If that isn’t enough, see a dermatologist about prescription options. Be very cautious with aggressive peels and lasers, as they can make melasma worse. Stay consistent and it will improve.