Electrolyte drinks better than water for long distance flights

Research carried out in Japan offers advice for those travelling on long-haul flights - consume a drink containing electrolytes or carbohydrates.A letter published in this month's Journal of American Medical Association, looks at research done by Japan Airline's Medical Services to find a way of reducing the risk of blood-clotting during long distance flights.

The authors noted that it is the potential for dehydration on long flights which increases the risk of deep vein thrombosis (DVT), causing blood clots to form in the legs. DVT increases the risk of pulmonary embolism, a potentially deadly condition that occurs when a blood clot lodges in the lungs.

Researchers noted that in a simulation of a long flight, the reduction of plasma volume (PV) observed during 10 hours of confinement in a chamber was achieved by an intake of isotonic-electrolyte solution. They noted that a combination of electrolytes and carbohydrates could further enhance hydration in this situation.

The study was carried out on 40 healthy men on a 9-hour flight. Some of the men were given Pocari, a beverage containing sodium, potassium and carbohydrate, which is manufactured by Otsuka Pharmaceutical Company in Tokyo, Japan. Other participants were given plain water. In total, they consumed about 1.3 litres of either drink.

Urine samples were collected every two hours during the flight and blood samples were taken after landing. Body weights were recorded before boarding and again after landing.

The findings indicate that those who drank the electrolyte drink had a greater net fluid balance at the end of the flight. They were also less likely to show an increased thickness in the blood in their legs.

The team concluded that Pocari, or a similar substance, may offer better hydration than water during long-haul flights.

The scientists added that other factors contribute to blood-clotting, and that passengers should take precautions when travelling for long periods of time.