24 Feb 2015

Let them eat nuts – and five other food fad U-turns

Eating peanut products at a young age dramatically cuts the risk of allergy, research suggests. Here are five other food studies that busted public opinion.


A study by King’s College London found that the risk of developing a peanut allergy is cut by over 80 per cent if babies eat peanut products.

The evidence contradicts years of official advice – which has been to avoid exposing young children to peanuts for fear of encouraging an allergy in later life.

Here are five other examples of health stories with conflicting research:

Red wine

Red wine frequently receives good press and is often cited as a healthy form of alcohol.

Scientists said that, when drunk in moderation, it reduces “bad” cholesterol, prevents blood clots and could even extend life.

Last year, however, a team of scientists monitored the health of 800 villagers in Italy and found no evidence that red wine stops heart disease or prolongs life.

Other research has also concluded there is no safe limit for alcohol consumption for pregnant women. However, different studies have disputed this.

Fruit Juice

Fruit juice

For decades fruit juice was seen as a healthy option. The government pushed it as one of the recommended five-a-day portions of fruit and vegetables, and it was cited as a good source of vitamin C.

But in recent years scientists have warned of the high levels of sugar in fruit juice, with some research claiming it contains as much sugar as many classic fizzy drinks.

Last year Susan Jebb, a government adviser and head of a diet and obesity research group at Cambridge University, said that the government’s official advice that a glass of fruit juice counts towards your recommended minimum five-a-day servings of fruit and vegetables should be changed.

Science Editor Tom Clarke writes:

So there's been an abrupt u-turn over the advice on peanuts. But unlike other "new research suggests..." headlines it seems the evidence for a peanut parental advisory was never really there in the first place.

If anything this research is an extreme example of the nutty way science moves forwards: zig-zaging self-correction as it lurches towards better knowledge.

It now looks like peanut allergies were on the rise in recent decades due unwittingly conflicting health messages. In the 70's parents were advised to keep kids away from peanuts because they were (and remain) a serious choking hazard. But in fact this advice may have contributed to peanut allergies by denying children early exposure to low-doses of peanut. Which, this new research suggests, would actually prevent allergy (provided the nuts are in a baby-friendly form like peanut butter.

The exciting challenge now is to see whether allergies to things like egg, fish and dust-mites work in a similar way.


The idea that eating more than three eggs a week was bad for you was long-held by much of the British public, mainly because people thought it increased cholesterol levels.

But research in 2009 by the University of Surrey said that limiting egg consumption has little effect on cholesterol levels.

“The UK public do not need to be limiting the number of eggs they eat – indeed they can be encouraged to include them in a healthy diet as they are one of nature’s most nutritionally dense foods,” said researcher Professor Bruce Griffin.

Saturated fats

In 2013, doctors declared that the risk from saturated fat causing heart disease was being “overstated and demonised”. Dr Aseem Malhotra said that it was time to “bust the myth of the role of saturated fat in heart disease”.

However, the British Heart Foundation said that there was conflicting evidence, and “lowering cholesterol levels lowers risk”.

Red meat

Regularly indulging in a steak or bacon sandwich raises your risk of heart disease and cancer, headlines often suggest.

On the downside, red meat is high in saturated fat. But it is also a good source of protein and contains vital nutrients, like iron and vitamin B12.

Researchers from the European Prospective Investigation into Cancer and Nutrition (Epic) followed half a million people in 10 countries for more than 12 years.

Eating moderate amounts of red meat had no effect on mortality, their research said.

But it also found that eating too much processed meat increases the risk of heart disease and cancer.