Is too much animal protein really 'as bad as smoking'?
Study links protein to cancer, but not everyone is convinced by latest headline-grabbing report
EATING too much animal protein could be as dangerous as smoking, a controversial new report has claimed.
The US study – which drew on results from people who took part in the National Health and Nutrition Examination Survey (NHANES) – found that middle-aged people who eat a large amount of animal products are nearly four times as likely to die of cancer as people who have a moderate or low protein diet, the Daily Telegraph reports.
"We provide convincing evidence that a high-protein diet – particularly if the proteins are derived from animals – is nearly as bad as smoking for your health," said Dr Valter Longo, of the University of Southern California.
However, nutrition experts say that it is too soon to draw any such conclusions from the study, and some have labelled the findings wrong "and potentially even dangerous", The Guardian reports.
"Sending out [press] statements such as this can damage the effectiveness of important public health messages," says Gunter Kuhnle, a food nutrition scientist at Reading University. "They can help to prevent sound health advice from getting through to the general public. The smoker thinks: 'Why bother quitting smoking if my cheese and ham sandwich is just as bad for me?'"
Heather Ohly at the European Centre for Environment and Human Health in Exeter reinforces the views of Kuhnle: "Smoking has been proven to be entirely bad for us, whereas meat and cheese can be consumed in moderation as part of a healthy diet, contributing to recommended intakes of many important nutrients."
Prof Tim Key, a Cancer Research UK epidemiologist, says: "Further research is needed to establish whether there is any link between eating a high protein diet and an increased risk of middle aged people dying from cancer."
But the US study is not unusual in coming to a headline-generating conclusion. Here are some other recent controversial medical reports:
- Last year the NHS published an article to warn people about the unknown effects of the 5:2 diet – a radical approach to dieting based on a principle known as intermittent fasting (IF) – where you eat normally for five days a week and then fast for the other two. The NHS sought to clarify that while there could potentially be some benefits to such diets, there "is also still a great deal of uncertainty about IF with significant gaps in the evidence". The report said that fasting is not always safe and recommended that people talk to their GP before attempting the 5:2 diet.
- A report covered by the New York Times in May last year undercut years of public health warnings on salt intake to argue that there is "no good reason based on health outcomes for many Americans to drive their sodium consumption down to the very low levels recommended in national dietary guidelines". Bonnie Liebman, director of nutrition at the Center for Science in the Public Interest, said "it would be a shame if this report convinced people that salt doesn't matter".
- Experts continue to publish contradictory findings on the health effects of wine. The Daily Mail notes that some experts suggest that wine can help prevent cancer, heart disease, stroke, dementia, and early death, while others say drinking wine can lead to serious health damage, causing cancer, heart disease, stroke, infertility and "myriad other disorders."