Dr Amir Khan has urged all Brits about to jet off on their summer holidays to follow his advice on staying healthy during flights, specifically to avoid blood clots.
Risk of blood clots on flights
The NHS warns that anyone travelling for four hours or more — by air, car, bus, or train — is at risk of blood clots forming. Known as deep vein thrombosis (DVT), this occurs when blood flow slows down, a blood vessel is damaged, or blood clots too easily.
The danger arises when a DVT breaks off and lodges in the lungs, causing a blockage known as a pulmonary embolism (PE), which can be fatal.
Dr Khan's advice
Speaking on the No Appointment Necessary podcast with co-host Cherry Healey, Dr Khan said: "People worry about blood clots on flights, right? So you want to reduce your risk of that happening."
He advised: "Every one to two hours you should be getting up or having a little wander up and down the plane, or doing your calf movements where you're stepping up and down on the seat—you know, while you're sitting down."
He also warned against taking aspirin as a precaution: "There is no evidence it reduces your risk of a blood clot, but there is plenty of evidence it increases your risk of bleeding. So do not take aspirin if it's not prescribed for you or not recommended to you. Don't take it as a 'just in case I get a blood clot' kind of medication. It doesn't do that."
He added: "And then, the other big thing, what blood loves is lots of volume and fluid, so drink water. Drink lots of water on that flight."
Symptoms of DVT and PE
According to the NHS, symptoms of DVT in the leg include throbbing pain in one leg (rarely both), usually in the calf or thigh; swelling in one leg; red, blue, or darkened skin around the painful area (harder to see on brown or black skin); and swollen veins.
DVT can also occur in the arm, and sometimes the only symptom may be pain in the lower tummy, which is a symptom of pelvic vein thrombosis, though this is rare.
Anyone with suspected DVT should ask for an urgent GP appointment or ring 111. Pregnant women can also call an early pregnancy unit (if less than 20 weeks) or their maternity unit.
Go to A&E or call 999 if you have DVT symptoms and feel shortness of breath or have chest pain. Do not drive yourself.
Symptoms of a pulmonary embolism include difficulty breathing that comes on suddenly, chest pain worse when breathing in, and coughing up blood. Seek emergency help if you have severe difficulty breathing, pain in the chest or upper back, a very fast heartbeat, or if someone has passed out.
Treatment and prevention
People with DVT or PE are often given an injection of anticoagulant to stop the clot growing and prevent new ones. If PE is confirmed, anticoagulant injections continue for at least five days, followed by tablets for at least three months. Treatment is usually successful if detected early.
To prevent clots, the NHS recommends wearing loose-fitting clothing, sitting comfortably with leg room, drinking plenty of water, standing regularly, moving feet and toes, wearing flight socks, and pressing the balls of your feet against the floor.
Bacteria on planes
Dr Khan also warned about harmful bacteria on planes due to the large numbers of people and destinations. He said: "When people are on planes, A) they might have been travelling from somewhere where bacteria that you're not used to are, but B) not everybody washes their hands when they go to the toilet, and we know this, and it's gross."
He advised using hand sanitiser and wiping down surfaces: "So I would say, yes, hand sanitiser, and do have a little alcohol wipe down."
