In the sun

How do once-a-day sunscreens actually work?

“Once-a-day sunscreens contain ingredients that ensure the product remains bound to the
surface of the skin, while still allowing the skin to breathe,” explains Clare O’Connor, UK sun care adviser at Boots.

“The ingredients form a protective film that is highly resistant to rubbing or washing off – but you must apply it correctly to benefit from the full UV protection. The recommended amount is two milligrams of product for every square centimetre of skin – that equates to an amount the size of a £2 coin to cover the whole of one arm and hand. It takes approximately three tablespoonfuls of product for a full body application.”

Can I get sunburnt through a window?

Ordinary glass absorbs 97 per cent of the UVB rays that cause sunburn and some skin cancers – but only 37 per cent of UVA radiation, responsible for ageing.

“This translates to a protection of about SPF30, so you can still get burned with long exposure,” explains Mike Wakeman, pharmacist and healthcare consultant for BioCare.

“Car windscreens have a plastic layer bonded between two layers of glass and this blocks all the UVB and 80 per cent of the UVA, making sunburn very unlikely.”

But studies show that sitting at windows for long periods while driving or working can increase wrinkles on one side of the face, so apply an SPF if you drive a lot.

… Or in the shade?

Yes. “As much as 85 per cent of ultraviolet (UV) radiation reflects from surfaces, such as sand, concrete, water and grass, and can hit your skin, even if you’re sitting under a tree or sun umbrella,” warns Clare.

Will a T-shirt prevent burnt shoulders?

“As a rule, light-coloured and loosely-woven fabrics don’t offer very much protection from the sun,” says Clare.

“To test if a fabric can protect your skin, hold it up to the light. If you can see through it, then UV radiation can penetrate it – and your skin. Protection is reduced further if it gets wet.”

Consider investing in UV protection sun tops – especially for your children.

What medications react with sunlight?

Medications that can increase sun sensitivity and also cause a sun allergy include coal tar, antidepressants, antibiotics, non-steroidal anti-inflammatories and sulphonamides but this is not an exhaustive list, explains Dr Steven Iley, medical director for AXA PPP Healthcare’s specialist health services division.

“Always read the label of your medication and discuss with your doctor if you have concerns,” adds Angela Chalmers, Boots UK pharmacist.

On the plane

Why does alcohol have more effect when we’re flying?

At altitude, the air in a plane’s cabin is less dense than it is on the ground and this affects the way the body processes oxygen in the blood stream, explains Mike Wakeman of BioCare

“The aircraft cabin air is also drier and this adds to the desire to drink more.

“One drink in the air will affect you the same as two or three drinks on the ground, so limit your intake and drink plenty of water to counteract dehydration from cabin air.”

When am I most likely to get jet lag?

“Jet lag is worse travelling west to east as the body clock adjusts much easier to a longer day, which occurs when you travel from east to west,” explain Dr Iley of AXA PPP Healthcare.

“As a general rule, every hour of difference takes one day to overcome.

“The best prevention is to minimise alcohol and get into the local time zone as quickly as possible, even on the flight.

“Meals, sleep, exercise and exposure to light should all be taken in the local time zone as soon as possible.” Check out the jet lag calculator at

Should I take aspirin before a long flight to avoid DVT?

“Aspirin has specific effects and also side effects so it should only be taken if recommended by your doctor,” warns Dr Iley. “There are lots of other ways to help prevent DVT,” agrees Angela Chalmers, of Boots.

“For example, it’s important to keep moving – take off your shoes to allow you to wiggle your toes and circle your ankles at regular intervals.

“And walk up and down the aisle to keep your blood circulation flowing freely.

“Also sip water throughout your journey to help keep blood at the right thickness.”

Am I more likely to pick up a cold virus when flying?

There’s no good scientific study on this but the consensus is that, yes, it does become easier to get a cold when travelling, says Dr Elaine Tickle, private general practitioner (

“Firstly, the air dries the nasal cavity, so the immune barrier is not as good.

“Secondly, recirculated air in the cabin means exposure to germs in the environment is more of an issue.

“And, thirdly, if we are stressed – and who isn’t when going through an airport – there is a drop in immune function.”


Why do I get cramp swimming in the sea?

Lots of things can cause cramps, especially in colder water, says Mike Wakeman.

Over-exertion can cause a build-up of lactic acid in the muscles, while not warming up the muscles can also contribute. Dehydration can affect your electrolyte balance and not having enough magnesium or potassium in your blood stream affects muscles. Try eating a banana 30 minutes before swimming.

Can I pick up diseases swimming outdoors?

Open water swimming can increase the risk of gastrointestinal infections as well as respiratory, skin, ear and eye infections, warns Mike.

“Symptoms will generally be mild, caused by organisms, such as norovirus, giardia and cryptosporidium. However, there is also a risk of more severe infections caused by organisms such as E.coli, which may lead to more severe gastrointestinal illness and leptospirosis, which affects the liver and kidneys.”

Can I swim after eating?

It’s not exactly dangerous but probably not sensible with the blood supply diverted for digestion, said Dr Richard Dawood, author of Travellers’ Health: How To Stay Healthy Abroad.

It is dangerous, however, to swim after drinking alcohol. It causes impaired judgment, carelessness and loss of balance. Almost a third of drownings happen after drinking alcohol.

Bites and stings

Will drinking gin and tonic keep the mosquitoes at bay?

No, says Dr Iley. “The amount of quinine in a normal gin and tonic is not enough to provide any meaningful protection against mosquitoes. A proper repellent is key.”

Should I spray repellent on clothes or skin?

“It doesn’t really make a difference,” says bite expert Howard Carter, “but DEET-based repellents tend to destroy natural fibres and can stain. Either apply to your skin before dressing or use a deet-free repellent, such as Incognito (£9.95 at” Perfume and hairspray can attract mosquitoes.

What’s the best way to remove insect stings?

Scrape – not squeeze – the sting. Fingers can actually squeeze more venom into the body, so use a flat object, like the blunt edge of a knife or a credit card, to scrape away insect stings as quickly as possible and apply a cold compress. If you get swelling around the bite, apply antihistamine ointment or cream.

What’s the best way to prevent mosquito bites?

Mosquitoes typically bite between dusk and dawn, so use repellents formulated to last 12 hours.

Close up your sleeping quarters and use a mosquito net.

Make clothing mosquito and tick-repellent with a permethrin spray (£7.99,