Food nutrition reporting needs more science

• ‘The science is complicated’  
• ‘Reducing the amount of saturated fat in a diet’
• ‘So why should it be any different for food’

Any journalist worth their salt knows the value of an eye-catching headline. But statements like ‘Fat is good for you’, ‘Potatoes increase blood-pressure’ and ‘Vegetables can seriously damage your health’, are liable to take sensationalism to new levels.

Yet, these have all appeared on the pages of national newspapers in recent times.

If such counter-intuitive stories weren’t confusing enough, the internet is now awash with websites and blogs from so-called nutrition experts, many of whom are keen to point out the ‘evils’ of processed food while claiming their own diet regimes to be the panacea for all of life’s ills.

It’s little wonder that the food industry feels so embattled.

One leading nutrition scientist, however, is on a mission to redress the balance. Professor Christine Williams believes it is time for manufacturers, retailers, scientists, learned societies and industry bodies to work together to put sound science back on the front foot.

But in the face of so much dubious reporting, and with the level of suspicion towards the food industry at an all-time high, just how likely is she to succeed?

Williams is professor of human nutrition and pro-vice-chancellor (research and innovation) at the University of Reading (see box).

However, she has used her position as both governor and chair of trustees at the British Nutrition Foundation (BNF) to initiate a working group to look at ways of promoting better nutrition science.

She says there are two main reasons why media reporting around food nutrition can be so misguided.

‘The science is complicated’ (back to top)

“First, the science itself is complicated, incomplete or evolving and it’s sometimes difficult to get clear answers from the evidence available. Secondly, journalists tend to be opportunistic, so will look for stories that go against the grain,” she explains.

Problems tend to occur when the media pick-up on a “badly executed” cohort study – a study that collects information such as diet and health characteristics at a baseline point and then follows people up over a long time to assess health outcomes.

Williams says people’s diets can change significantly over time and, for the poorer studies, these changes are not measured or accounted for.

Another problem, she argues, is that some studies are small and apply inadequate or inappropriate statistical methods. They can also fail to take into account the fact that many people misreport what they eat during the measurement of their baseline food intake levels.

But aside from the problem of dietary measurement, Williams says these types of cohort studies can only make observations on possible associations between a dietary factor and, say, heart disease.

“They give an indication of the types of diets, foods or other factors that may be more or less harmful against heart disease. However, they can never provide definitive proof that diet causes a specific disease,” she explains.

What scientists and public health experts do, claims Williams, is go beyond the cohort study. “Are there plausible mechanisms that could explain the findings from the cohort studies?

“Are there any intervention studies where people’s diets, and exposure to risk, have been changed and the health outcome – or risk factors for disease – changed as a result of a specific diet?”

For heart disease, she maintains there is “very strong evidence” that one way diet affects the heart is through blood cholesterol.

‘Reducing the amount of saturated fat in a diet’ (back to top)

“Time and again, these types of intervention studies show that reducing the amount of saturated fat in a diet lowers blood cholesterol and this is consistent with many of the earlier cohort studies that show people who eat a lot of saturated fat have a high risk of heart disease.

“So we can put these two types of research findings together and be fairly confident that the cohort studies are correct.”

But when the press seize on studies that haven’t been rigorously examined, or where findings are premature and not corroborated, Williams says organisations like the BNF are left trying to “firefight” the consequences, which is often consumer confusion about diet and mistrust in the science of nutrition.

The current working group is looking to address this problem by adopting a more pre-emptive approach. While it’s likely to be a couple of years before its conclusions are published, the BNF is already starting to become more consumer-facing, Williams claims.

“The organisation has started blogging, and adopting greater use of social media to engage more with younger people,” she says.

“It’s also got a big taskforce publication on diet and cardiovascular disease coming out this year.”

It’s clearly an admirable tactic. But it doesn’t address the perception problem that both the BNF and nutrition scientists face – that by being partly-funded by industry, they are seen as being in the pocket of manufacturers and retailers.

While Williams believes there should be a “fair amount” of funding from government, the issue for her is that industry support is also important.

In addition to funding, she says industry can provide experimental foods and diets of a quality that could never be provided by a research organisation. Yet, she is concerned that such collaborations are looked on with suspicion and mistrust in some quarters.

“A lot of our great research engineers in this country carry out work for the automotive industry, as they are likely to develop the latest and best technology for new cars. So why should it be any different for food?” she says.

‘So why should it be any different for food’ (back to top)

“When I conduct intervention studies on different types of fat, I’ve asked suppliers to make-up margarines, oils, ready meals, puddings, biscuits, crisps and so on. Never have they placed conditions on my publications.

“And if the work comes out unfavourably from their perspective, I am still able to publish it – and have done so.”

A collaborative approach with industry is preferred by Williams, but that doesn’t mean processors are absolved of their responsibilities.

“We’ve still too much sugar in our diet, and it remains a problem – particularly in regard to calorie intake in childhood and consequent risk of obesity. But it is important to be clear that reducing sugar in the diet will not be the only solution to the obesity crisis,” she says.

“The problem for manufacturers is what do they replace sugar with? Some are wondering whether they should put fat back in, while others – like confectionery makers with chocolate bars – have been changing pack-sizes.

“Unfortunately, this leads to consumers becoming cynical about their profit motivations, and it also doesn’t reduce the sweetness of the chocolate, so it doesn’t help to change people’s eating habits.”

Williams believes the solution lies in voluntary product reformulation over a number of years, allowing people’s tastes to change gradually. She also claims consumers should acknowledge that they have a role to play.

“Processors successfully managed to reduce salt levels voluntarily, so there’s no reason why they can’t do it for sugar. But equally, consumers need to start facing up to reality,” she believes.

“The simple equation is that if we eat more calories than we use, we’ll put weight on. We should start acknowledging some foods will have to cost more and we need show moderation about certain foods.”

So, for consumers, restraint appears to be the watchword of our times. We can only hope newspaper editors take the same approach.