Tuesday, April 13, 2010
How the (now discredited) five-a-day mantra was born
It all began with a catchy number and a marketing campaign — not hard science -- just like the "safe" alcohol intake allowances that governments proclaim. Official health advice again shown to be unworthy of trust
It is one of the most successful indoctrinations in modern Britain, filtering into every aspect of public life.
I start my day on a bus decorated with the injunction to eat five-a-day, I drop my son off at a nursery where he learns to count using the Government’s five-a-day fruit and vegetable quota, and at the supermarket it is slapped anywhere it will confer a commercial advantage.
We have swallowed it whole and, when we swallow the five-a-day, we believe we gain a kind of magic protection. Or we did until last week’s news that the biggest study of its kind, published in the Journal of the National Cancer Institute, showed that the reduced cancer risk by eating five-a-day didn’t add up to more than a hill of beans.
This made me a bit queasy. Where did this five-a-day order — promoted by government, the NHS, the American Cancer Society and more than 25 other countries — come from? Fuelled by a two-a-day-diet — ketchup and an olive — I tracked the global health campaign. The trail took me back 25 years, to a woman in California, and left me with little appetite for public health advice.
“The world has gone mad with targets,” says Tim Lang, the first stop in my quest. I’d tried the Department of Health, and was told its five-a-day programme was announced in 2000, based on World Health Organisation advice about the role of diet in cancer, but that didn’t really tell the full story.
Lang, a professor of food policy at City University, remembers it differently. It was the late 1990s, the new Labour Government had come to power and set about instilling a target-driven culture in every aspect of British life.
“We all understand targets in the policy world. I remember being in the room when we were being briefed by Americans on five-a-day, which we adopted from them. They chose five partly as it was considered a nice round sum and partly because it seemed possible, given how low consumption of fruit and vegetables was.”
The Department of Health was searching for a motivational tool for a nation of poor eaters and the ready-made American campaign based on the number five seemed catchy. What, I say? Can this really be true — the five in five-a-day was chosen for marketing purposes?
“Five-a-day was an attempt to shift culture, which is not the same thing as saying eating five-a-day will protect everyone. It was a political judgment, but not a bad one.”
Hippocrates said “let food be thy medicine”, but was this “let modern branding be thy medicine”? Walter Willett, professor of nutrition and epidemiology at Harvard University, is one of the world’s most eminent nutrition researchers. His career, though, has been distinguished by disproving excitably reported ideas about “superfoods” rather than forming them.
In 1991 the American Government adopted the five-a-day policy, as growing numbers of experts were stating that bad food was causing cancer. First and foremost among them was Britain’s esteemed Sir Richard Doll, the scientific hero who established the link between cigarettes and cancer. In 1981 he estimated that a third of cancer deaths in the West could have been avoided with a better diet.
When Sir Richard spoke, the world took notice and, by 2007, says Willett, the experts proclaimed that eating a load of fruit and veg could reduce your cancer risk by 50 per cent. The American National Cancer Institute upped its recommendations to nine-a-day.
“It was a pretty rough, arbitrary number, which is always the case with any target,” says Willett. But, he adds, the studies were fatally flawed. “They were based on retrospective evidence — asking people about their diet after they had already got cancer, which can lead people to report differently. Also, the control groups were not perfectly random, the people who volunteer for that kind of thing are much more health-conscious individuals.”
So, from where did the US Government get the idea for the number five, if not the scientific studies? I was closing in. Marion Nestle, nutrition professor at New York University, thinks she remembers exactly where.
“It was Susan Foerster, the head nutritionist in California. She had the bright idea of promoting fruit and vegetable consumption in a state which was a big fruit and vegetable producer.”
The American National Cancer Institute admits that “no studies have tested the impact of specific numbers of servings on cancer risk”. But it says five was chosen in California in 1988, as it doubled the average consumption, and “the number five was memorable and provided a platform for creative message and programme delivery”.
In America now, the five-a-day message is “invisible; [it has] completely dropped off the radar”, says Nestle.
Britain, though, has taken California’s 1980s marketing policy and run with it.“We have to abandon this idea that there’s something miraculous in diet,” says Paulo Boffetta, the doctor behind last week’s study. “It’s not true for fruit and vegetables as a whole, and even less true for fruit and vegetables individually.”
And by the way, as everyone I spoke to emphasised, an unexpected surprise of all this research is the discovery that although it may not do much for cancer, eating fruit and vegetables is good for your heart. How many a day? Don’t ask. [Rubbish! The findings for heart disease were inconclusive]
University-educated women are the heaviest drinkers
This is not exactly surprising. Alcohol plays a big part in student social life (dare I mention the Bullingdon club?) -- and apparently the habit persists. Additionally, smarter people tend to earn more so can more easily afford wine with dinner etc.
Women who went to university consume more alcohol than their less-highly-educated counterparts, a major study has found. Those with degrees are almost twice as likely to drink daily, and they are also more likely to admit to having a drinking problem. A similar link between educational attainment and alcohol consumption is seen among men, but the correlation is less strong.
The findings come from a comprehensive study carried out at the London School of Economics in which researchers tracked the lives of thousands of 39-year-old women and men, all born in the UK during the same week in 1970.
The report concludes: "The more educated women are, the more likely they are to drink alcohol on most days and to report having problems due to their drinking patterns. "The better-educated appear to be the ones who engage the most in problematic patterns of alcohol consumption."
Women's alcohol consumption can even be predicted from their scores in school tests taken when they are as as young as five. Women who achieved "medium" or "high" test marks as schoolgirls are up to 2.1 times more likely to drink daily as adults.
The authors of the report, Francesca Borgonovi and Maria Huerta, suggest several possible explanations as to why better-educated women drink more.
They tend to have children later, postponing the responsibilities of parenthood. They may have more active social lives or work in male-dominated workplaces with a drinking culture. As girls, they may have grown up in middle-class families and seen their parents drink regularly.
In the long-term study, the LSE team followed all the people born in Britain during one week in 1970, asking them questions about their lifestyle at regular periods throughout their lives.
The number of people for whom information was available has varied over the course of the research between 9,665 and 17,287.
The researchers took account of each individual's school test results and level of academic attainment, as well as their answers to regularly-administered surveys in which they were asked questions such as "Have you ever felt you should cut down on your drinking?" and "Have you ever had a drink first thing in the morning to steady your nerves or get rid of a hangover?"
Women with some educational qualifications were 71 per cent more likely to drink on most days compared to women with no qualifications. Women with degree-level qualifications were 86 per cent more likely to do so.
Higher educated women were 1.7 times more likely to have a drinking problem, as assessed through their questionnaire answers, than their less-well-educated counterparts. Women who scored highly in tests while at school were also at greater risk of having drinking problems.
Whereas women with medium or high childhood test scores were up to 2.1 times more likely to have a drink most days, men who scored similarly-high scores were only 49 per cent more likely to do so.
"Both males and females who achieved high-level performance in test scores administered at ages five and 10 are significantly more likely to abuse alcohol than individuals who performed poorly on those tests," says the report, in the journal Social Science and Medicine.
According to the study, a substantial part of the educational effect is likely to be due to better-educated women having more opportunities and tending to have middle-class lifestyles, exposing them to circumstances that favour alcohol consumption.
"Reasons for the positive association of education and drinking behaviours may include: a more intensive social life that encourages alcohol intake; a greater engagement into traditionally male spheres of life, a greater social acceptability of alcohol use and abuse; more exposure to alcohol use during formative years; and greater postponement of childbearing and its responsibilities among the better educated," says the report.
Commenting on the findings, a spokesman for the Alcohol Concern charity said: "This raises concerns which need to be addressed. "People with higher qualifications have more disposable income, and we have seen a trend where there has been an increase in the marketing of wine, particularly aimed at working women.
"People who abuse alcohol face a higher risk of suffering from health problems incluidng cancer, liver cirrhosis, lung and cardiovascular disease, and mental and behavioural issues."
Posted by jonjayray at 7:38 PM