Addressing the obesity epidemic by taxing sugary soft drinks sounds good in theory but it appears to fall down in practice. How could a taxation strategy be made to work?
Obesity is proving to be an intractable public health problem demanding innovative solutions and one idea that is attracting attention is the taxation of sugar-sweetened beverages. The theory is simple enough. Basic economics tells us that if the price of sugary soft drinks were to rise, their consumption would fall; lower intake should mean lower calorie intake which would lead to lower body weights. But would it work in practice?
The Ohio experience
A recent research study conducted in the United States provided some interesting insights. Taxing soft drinks has a long history in the US and occurs in many states today, though historically the rates have been low and the purpose has been to raise revenue. But there was an interesting exception. In 1992, the state of Ohio introduced high taxation of sugary soft drinks which was then repealed at the end of 1994. This provided an opportunity to test the effect of taxation of soft drinks on body weights over a period of two years. The researchers compared changes in body weights in Ohio over this period to (1) all other states that had no increased taxation and (2) a bundle of states with the same mean BMI as Ohio. The researchers found:
… very little evidence that the large tax imposed in Ohio had any detectable effect on population weight … our results cast serious doubt on the assumptions that proponents of large soda taxes make on its likely impacts on population weight.
How come? Why didn’t quite high taxation of sugary soft drinks affect body weights?
Although the headlines have got it wrong the science relating to saturated fat and heart disease has evolved considerably. But Australia’s public health nutrition policy makers are blissfully unaware and are implementing science that’s out of date.
In March yet another headline appeared in the mainstream media stating ‘No link found between saturated fat and heart disease’. The media delights in stories about diet that appear to contradict the status quo and, of course, relevant industry groups always put their public relations firms into action whenever an opportunity presents itself. Hence the misleading headlines.
Certainly there have been recent developments in how the coronary risk associated with dietary saturated fat is understood but it has to be said that the significance of these findings has still not fully registered with many nutritionists and policy makers in Australia, let alone the media. So let’s recap.
The way things were
Prior to 2009 many dietary guidelines around the world included a recommendation to eat less saturated fat on the grounds that it increased the risk for coronary heart disease. But there was always an unstated corollary to ‘eat less saturated fat’ i.e. eat more of something else. If your body weight is stable and you just eat less saturated fat you will start to lose weight, because saturated fat contains calories. To maintain weight while eating less saturated fat you have to eat more of other calorie-containing nutrients, such as carbohydrate, monounsaturated fat or polyunsaturated fat. So ‘eat less saturated fat’ really meant replace saturated fat with a healthier macronutrient.
The assumption of the old dietary guidelines was that it didn’t really matter what you replaced saturated fat with – it was thought that all replacements would lower the risk for heart disease. However, we now know that this assumption was wrong.
Public health nutrition is a noble cause but its practitioners are increasingly seeing their role in terms of the left-right political divide. But in doing so have they made public health nutrition a target?
Nobody seems to disagree with the idea that improving the nutritional quality of the national diet is a good idea but getting agreement on the best way of achieving it is another thing.
In the 1980s the approach to public health nutrition was characterised by ‘intersectoral collaboration’ – fostering links and cooperation between the agriculture, food processing, nutrition research and nutrition education sectors. The Heart Foundation’s Tick program was born in this era and was based around an acknowledgement of competing interests – the health experts wanted changes to the food supply; the food industry wanted a marketing advantage for the reformulation being requested; and a means of food approval was devised to consolidate the compromise.
Now it’s war!
Fast forward to 2014 and the environment is very different – the notion of collaboration is gone. Now, it’s war! Listen to the rallying cry from none other than Margaret Chan, Director-General of the World Health Organization, at a health promotion conference in Finland last year:
It’s not just Big Tobacco any more. Public health must also contend with Big Food, Big Soda and Big Alcohol. All of these industries fear regulation … This is formidable opposition … [There] is a failure of political will to take on big business … When industry is involved in policy-making, rest assured that the most effective control measures will be downplayed or left out entirely. This, too, is well documented, and dangerous.
Sugar-sweetened beverages are in the sights of public health nutritionists, especially in relation to obesity. But there is some good news: a fundamental shift from sugar-sweetened to non-sugar soft drinks is underway and the amount of sugar entering the national diet from these beverages is in long-term decline.
Despite all the interest in sugar in recent years Australian nutritionists don’t really know for sure whether sugar intake in Australia is going up, going down or staying the same. Unlike American nutritionists who have the findings from the ongoing NHANES series of nutrition surveys to go on, we have been hamstrung by the poor quality of our nutrition data. There are few national nutrition surveys to guide us.
In 2011, Dr Alan Barclay and Professor Jennie Brand-Miller collated the available Australian data and concluded that per capita consumption of sugar had decreased by 16% in Australia between 1980 and 2003. Their work was attacked with uncommon vigour. Apparently, this was not a message that some people wanted to hear. One concern expressed about their work was that Barclay and Brand-Miller had partly relied on ‘apparent consumption’ data, which the Australian Bureau of Statistics ceased publishing in 1998/99.
In a subsequent analysis by the commodity firm Green Pool, the apparent consumption data were updated and analysed, and again suggested a long-term fall in sugar consumption in Australia was underway. There were more howls of protest. Unfortunately, when the quality of the available data is ordinary this sort of debate ensues and we end up with lots of heat but little light.
Fructose has been accused of being the root of all dietary evil but at a symposium in Sydney this week Canadian researcher John Sievenpiper argued that fructose has been misjudged.
John Sievenpiper knows a fair bit about dietary carbohydrates and health. His team in Toronto recently conducted systematic reviews and meta-analyses evaluating the effects of fructose on body weight, blood pressure and glycemic control in humans. He discussed some of the findings at the ‘Sweet Symposium’ on 2 December.
The fructose-centric view
Sievenpiper reviewed the rapid evolution of what he called the ‘fructose-centric view’ in modern nutrition, which positions fructose as a central driver of the obesity epidemic and cardiometabolic risk. Certainly several lines of evidence had raised suspicions about fructose – apparent increases in fructose consumption were associated with increases in obesity in population studies; animal studies showed fructose had adverse metabolic effects; there were similar findings in some human studies; and an articulate anti-fructose champion, Robert Lustig, emerged and took his simple ‘fructose is toxic’ message to the general public. And the media loved it – even the ABC’s ‘science’ program Catalyst jumped on the bandwagon and pushed the idea around. In less than a decade the fructose hypothesis became an anti-fructose doctrine with a chanting chorus of true believers.
Media Watch, Australia’s leading forum for media analysis and comment, has lambasted the journalism behind the ABC’s recent Catalyst programs on cholesterol describing them as ‘sensationalist and grossly unbalanced’.
Giving up on the search for truth was the title of an article about declining standards of journalism penned by Nick Cater, the Editor of the Weekend Australian, on 2 November. Cater wrote By abandoning the pursuit of truth, modern journalism appears to have fallen for the philosophical error that blights modern academe … The empirical route to knowledge through investigation, observation and reason is rarely respected. Instead, journalists have come to believe knowledge comes through revelation … Cater was primarily talking about political journalism but his comments rang true in the light of the recent Catalyst programs on cholesterol.
Assessment by Media Watch
Fortunately, some journalists take their profession seriously. MediaWatch was scathing of the quality of the journalism behind the ABC’s Catalyst programs. For those who are unfamiliar with Media Watch, it is an ABC television program that analyses the media for Conflicts of interest, … deceit, misrepresentation, manipulation, plagiarism, abuse of power, technical lies and straight out fraud … Media Watch turns the spotlight onto those who literally ‘make the news’. We also keep an eye on those who try to manipulate the media: the PR consultants, spin-doctors, lobbyists and “news makers” who set the agenda’.
In commenting on the Catalyst programs, Media Watch presenter Paul Barry said Now, Media Watch is not going to take sides in this scientific debate. But looking at the journalism we’re almost as shocked as the doctors. Both episodes of Catalyst struck us as sensationalist and grossly unbalanced; and some of their so-called ‘experts’ had questionable qualifications.
The cholesterol controversy featured on the ABC’s Catalyst program had nothing to do with science – it appears to have been designed to sell palm oil. Was the Catalyst team naive or complicit?
ABC television’s science program Catalyst recently ran two programs purporting to expose the myths about cholesterol and cardiovascular disease. In the first program the role of saturated fat in increasing risk was challenged and in the second the efficacy of statin medication for lowering coronary risk was put under the spotlight.
The programs provoked a storm of controversy, even within the ABC, because of their bias and potential to mislead. The ABC’s own health reporter Dr Norman Swan was irate, declaring on Radio National that “People will die as a result of the Catalyst program …”. Swan also conducted an excellent interview with Professor Peter Clifton on The Health Report as a means of countering the mischief caused by his colleagues at Catalyst. It’s well worth a listen.
Catalyst used to be a respected, evidence-based science program. How did it come to this?
Public health advocates have consistently failed to get substantial Government support for their initiatives to tackle the obesity epidemic. And they only have themselves to blame.
Last week on ABC radio’s AM current affairs program the former chair of the National Preventative Health Taskforce lamented that the Government had failed to address obesity. In 2009, the Taskforce released a report titled Obesity in Australia: a need for urgent action which was supposed to be the springboard for Government action on the issue. Instead, the report was tossed onto a large pile of obesity reports and recommendations that have been ignored by our politicians.
What went wrong? Why did the then Government, which was favourably disposed to public health and disease prevention, fail to act? My guess is that it was the appalling quality of the report.
“The problem is that many dietitians around the world are telling people to have wholegrain bread when most wholegrain bread is roughly comparable to eating a bag of glucose.”
Last month Professor Jim Mann** addressed the annual conference of the European Association for the Study of Diabetes (EASD) in Barcelona on the controversial topic of carbohydrate quality. Although he was mainly talking about carbohydrates in the diets of people with diabetes, what’s good for this group is good for most of us.
Given the current hysteria about sugar it was interesting that Professor Mann had little to say about it. He indicated that the current EASD recommendation for the general population i.e. that total free sugars be limited to 10% of energy, was appropriate and was likely to be retained when new EASD guidelines are released. He had a lot more to say about starch.
Fifteen percent of Australian children head off to school without having had any breakfast and the figure is rising. Among secondary school students it’s closer to 20 percent. What are the implications and what should nutritionists do?
The CensusAtSchool survey
CensusAtSchool is an annual nationwide survey of students’ everyday lives, experiences, opinions and interests conducted by the Australian Bureau of Statistics. Participation is voluntary so the data produced are not necessarily representative of the whole school population, just those who completed questionnaires. Nevertheless, the findings provide insight into the trends, habits, attitudes and lifestyles of Australian students.
According to the latest survey of nearly 24,000 children, about 15 percent do not consume breakfast and the figure has been rising in recent years. There is considerable variation in breakfast skipping across Australia, from 12 percent of Victorian school children to over 22 percent in the Northern Territory.
Earlier reports from the same survey have highlighted how breakfast consumption declines as children get older. Typically about 7-8 percent of primary school children skip breakfast but the figure rises to about 20 percent for children at secondary school.