Why do some people get more insect bites than others? How to keep blighters at bay with the best insect repellents – and what to put on bites to make them disappear
Don’t you just love balmy summer evenings? Gazing upon a dreamy sunset, chilled cocktail to hand, lazing in the garden or on a balcony somewhere exotic... But with all this loveliness comes one major problem – insect bites, aka everyone’s least favourite summer holiday accessory. And of course, mosquitos (and other flying horrors) don’t take an equal opportunities approach with their campaign of terror – some people (like, sorry to be smug, me) escape unscathed, while others (like my poor husband) get blitzed into oblivion.
Why do mosquitos bite some people and not others?
I put this question, a perennial topic of debate during our family summer holidays, to Dr Raj Arora, NHS GP, aesthetic practitioner and founder of the Facebible clinic. Turns out you are more likely to get bitten if:
- You are pregnant
- Mosquitos like your body odour or skin microbiome
- You breathe out CO2 heavily
- You sweat a lot
Dr Raj explains: “Some studies have shown that blood type, our skin microbiome/bacteria, body odour, body temperature, genetics and carbon dioxide emitted from our breath can all influence the amount we are bitten,” she says.
And if you are pregnant, you may be more attractive to bugs. “This seems to be down to a combination of exhaling more carbon dioxide during pregnancy. But also the natural increase in body temperature that pregnant women experience is thought to be attractive to mosquitos,” says Dr Raj.
“Studies have shown that mosquitos are attracted to the lactic acid and ammonia found in sweat. Mosquitos can smell sweat and therefore are more likely to attack those who sweat excessively. Although some studies have focused on particular blood types - usually blood type O - being more attractive to mosquitos the science is contradictory and more research is needed.”
Does vitamin B12 prevent mosquito bites? Or vitamin B1 or even Marmite?
There's a good deal of chat on the web about this, but according to Dr Raj, there's nothing concrete to back up that mosquitos are put off by the yeasty smell of vitamin B12, the B vitamin that Marmite and Vegemite are rich in. Sorry but B1 won't help you either, as is anecdotally suggested. According to a research paper in 2005 on B vitamins as a home remedy against mosquitos and a more recent paper by Cambridge University Press in 2022 on thiamine (vitamin B1) as an insect repellent, "there is no solid evidence of vitamin supplementation helping."
Best mosquito repellents
“Repellents with 50% DEET (diethyltoluamide) are first-line recommendations to help prevent mosquito bites. This is safe for pregnant/breastfeeding individuals and also for children over the age of two months,” says Dr Raj. “If DEET is not tolerated, I recommend a repellent containing the highest strength formulation available of either icaridin (20%), eucalyptus citriodora oil, hydrated, cyclised or 3-ethlyaminopropionate.”
Apply it thoroughly and reapply frequently, says Dr Raj, especially if you’re somewhere hot or if you’ve been swimming. “And apply repellent after sunscreen, which should contain 30 to 50 SPF as DEET can make sunscreen less effective.”
Here is our pick of the best mosquito repellents:
The nuclear (DEET) option: Jungle Formula Maximum Pump Spray Insect Repellent, £9.49
The no-nonsense OG of mozzie repellents and the biggest seller in the UK, this contains 50% DEET plus plant extracts. It gets a thumbs up from Dr Raj.
The DEET-free doctor's choice: Incognito Insect Repellent, £9.35
If you’d rather go DEET-free (it can irritate skin), this is Dr Raj’s top choice. Containing citrus-scented Citrepel75, it also works on midges, ticks, horseflies and a host of other flying menaces.
The family-friendly cologne: Mrs White’s Unstung Hero Mosquito Repellent, £20
Beloved by beauty editors, this quaintly retro cult product is an eau de cologne, with a lemon tea fragrance that humans love but mozzies hate. Safe for children and you can spritz with abandon on your bedsheets too.
The aftersun: Green People Moisturising Aftersun with Insect Repellent, £16
Packed with plant actives – a type of citronella to repel bugs, chamomile to soothe and aloe vera to hydrate – this is DEET-free, suitable for pregnancy, babies over six months and people with sensitive skin.
The cult budget one: Avon Skin So Soft Original Dry Oil Spray, £5
This isn’t actually marketed as an insect repellent but people rave about its bug-beating qualities. A body oil containing citronella and jojoba, one bottle is sold every 25 seconds and at just a fiver, it’s well worth taking a punt on for itch-free summer evenings (with a side order of silky limbs).
The movie stars' choice: Alfresco Anti Bug Bite Moisturiser, £11.50
Never mind mosquito magnet, this mozzie-thwarting moisturiser is an A-lister magnet. Robert Redford, Kristin Scott Thomas and Penelope Cruz are among the actors who request a tube of this miracle worker, while shooting on location. If it’s good enough for them…
The Aussie favourite: Vanilla Mozi Outdoor Body Cream, $29.95 Australian dollars (about £15)
This is one for our Aussie readers (as it costs around £20 to ship to the UK). The Down Under brand’s body cream-cum-repellent, crammed with natural plant extracts, won a 2023 Get The Gloss Wellness Award so it’s a guaranteed good ‘un.
The cool new brand to prevent and treat: Etto The Pure Oil Spray £26.40
New to the UK at Sephora, Etto is an Australian brand based around pure tea tree and eucalyptus oils, widely used for their antibacterial and antifungal properties to treat cuts and scrapes (and bites). They have a herby smell that mozzies hate - making this spray-on oil your go-to natural bug repellent too. Blue Mallee eucalyptus oil, the one Etto favours is said to have a superior fragrance and we found it very pleasant to use. Its founder, Andrea Horwood, has an impressive beauty and wellness CV having founded Elle Macpherson's Welleco brand as well as mega suncare brand Invisible Zinc. They also do some great Tea Tree Micro-Dart Patches, £16.99 for nine, to put on spots - and bites!
How to treat mosquito bites
Missed a bit with your repellent? It happens to the best of us. Dr Raj suggests the following steps to treat bites:
- Use a cold cream or ice pack to soothe.
- If the bites are on your legs, keep them raised to prevent excessive swelling.
- Use painkillers if they are stinging and sore.
- Take antihistamines to relieve itching.
- Apply a bite cream. These usually contain a weak steroid such as hydrocortisone to treat swelling or redness/inflammation. Some creams also include an antibacterial/antiseptic. Most local pharmacies and supermarkets will have their own brands.
- Try a pimple patch, the sort you use to clear spots. Anecdotally, they can help. Try Etto, above.
And don’t just leave them to fester, keep an eye on them. “If a bite looks infected - signs of increased redness, swelling, pain, pus/discharge or getting worse over time - then this must be seen to by a medical professional - reach out to your pharmacist or doctor,” says Dr Raj. Finally, if you've been venturing a lot further afield than your patio, be aware that suspected malaria is a medical emergency. “If you have a high fever (38C) and are feeling unwell after travelling in a malaria high-risk country then you must see your doctor immediately,”