If you’ve ever wondered what the secret is to a long, happy and healthy marriage – the answer may be as simple as having separate beds, one sleep expert claims.

Not only will a couple escape arguments over blanket-hogging and non-stop tossing and turning — but they will have a proper night's rest and be healthier for it, Dr. Neil Stanley, the consultant who set up sleep laboratories at U.K.'s Surrey University, said.

"Poor sleep is bad for your physical, mental and emotional health," he said. "It increases the risk of stroke, heart disease and divorce."

On the other hand, if you enjoy sleeping in them same bed, then by all means don’t go out and buy that twin bed just yet.

"If you sleep perfectly well together, then don't change," Stanley said. "But don't be afraid to relocate."

If a husband or wife snores, twin beds might not be the best option, and the spouses should sleep in separate bedrooms, Stanley told the British Science Festival.

When one partner moves in his or her sleep, there is a 50 percent chance the other will also change position. Despite this, couples are reluctant to sleep apart, with just 8 percent of those in their 40s and 50s sleeping in different rooms.

Stanley also said the argument that it was comforting to sleep beside someone else holds little water.

"Sleep is the most selfish thing we can do," he said. "People say that they like the feeling of having their partner next to them when they are asleep. But you have to be awake to feel that."

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