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Fasting before fat tests “may be unnecessary”

11 November 2009

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The practice of GPs telling patients to fast before taking cholesterol tests may be unnecessary, new evidence has shown.

The usual routine has been to instruct patients not to eat in the 12-hour period before a blood test, which meant anyone having the test in the morning would have to go without breakfast.

If someone had eaten before the test, they were often told to make a new appointment as it was believed that taking the sample on a full stomach would affect test results.

But a new analysis of data on more than 300,000 people from around the world indicates that this assumption was wrong.

Researchers funded by the British Heart Foundation (BHF) pooled together information from 68 long-term studies in 21 countries.

They found that blood tests on non-fasted patients predicted the risk of heart and artery disease just as well as tests on patients who had not eaten.

Professor John Danesh, from Cambridge University, who led the research published in the Journal of the American Medical Association, said: “For decades, people have been asked to fast overnight before their cholesterol tests.

“These findings indicate that cholesterol measurements are at least as good – and probably somewhat better – when made without fasting.”

Copyright © Press Association 2009

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