Sugar v Fat: Is it personal?

Post date: 03-Feb-2014 15:37:56

This week saw another nutrition programme on our screens (Horizon:Sugar v fat) where the brothers Dr Chris and Dr Xand Van Tulleken set about an investigation into one of the hot topics of the day (the clue is in the title). The pair used themselves in a small experiment that while acknowledging the very small sample size (n=2) drew attention to the fact that they were twins and this was relevant due to their genetic similarity. They then went on a 4 week diet of either no carbs or no fat, undertaking a series of physical, nutritional and metabolic assessments to illustrate the differences in their diets. Despite the title of the programme, and much of the content, suggesting it was a head to head fight with only one winner, the main conclusions, based on their own findings and those of wider research, were that foods high in both should be limited, extreme diets are to be avoided and exercise is key to weight loss. All good so far. It was then suggested that “it is up to you” to make the changes and while this phrase loses some of the pairs compassion when written down (they did include themselves in this call to action) it was a throw-away comment that made me want to write this article. A quick glance on twitter presented the usual comments from people that know far more than me about particular nutrients, percentages and combinations and who were identifying mistakes in the documentary's methodology as well as making slightly sneering comments about the lack of GPs' nutritional knowledge. I wouldn’t want to disagree with any of these comments as they may well be right, I do however have a problem with over complicating nutritional science and in particular the information that is put before the general public. There is a general belief that the more information that is put in front of someone, the better decisions they will make but having only recently read “Nudge” and “Thinking Fast and Slow” there is a body of research that suggests that too much information leads to people making poorer decisions rather than better ones. It was Herbert SImon that first suggested the concept of “bounded rationality” in which the rationality of an individual’s decision making is limited by the information they have, the cognitive limitations of their minds, and the finite amount of time they have to make a decision in, this in contrast to the view that decision-making is a fully rational process of finding an optimal choice given the information available. Before you try and put yourself on a pedestal of superior intelligence, the second issue of cognitive limitations of the mind can be applied to all of us, just think how much of a phone number you can remember, or how stressed you might find buying insurance or deciding on an energy supplier. Add the realities of modern busy lifestyles and you soon realise that simply writing a good nutritional plan for a client does not mean they will have the capacity to follow it for the rest of their life. This may seem slightly patronising but it is a indicative of the fact that most people know what a sensible diet is, but adopting one and sustaining it is a very different issue. We seem desperate to hang on to the notion that we are all free-living individuals that can make our own path through life unfettered by external forces and ironically this mindset is perpetuated by most marketing that projects images of “free-living” spirits all buying the same mobile phones. When it comes to nutritional advice I agree that “simplicity is the revelation” (Caulfield, 2012) and in his excellent book, Tim Caulfield goes on to suggest that we should all become conscious of the twisting forces that are working on us and that we become more aware of portion sizes, peer pressure and wider social influences on our diets.

Just recently I was invited to a conference run by The Westminster Food Forum an organisation that attempts to “help shape the policy agenda”. Despite being “strictly impartial” they also claim to “to make it as easy as possible for policymakers to be at our meetings so that other delegates can seek to influence the choices that they make”. I was struck by some of the language that the WFF used on their website and the (not so) subtle nods to how government policy is influenced. Similarly, last week there was a physical activity event hosted by Public Health England that caused a stir on twitter when Nick Cavill reported that all 7 of the panel would take funding from Coke to promote physical activity. While many of the twitterati suggested we should “take their money and run” I am more of the belief that this is just another way that Big Food can influence the discussion by raising the profile of physical activity/inactivity in the obesity discussion and deflecting from their own influence.

The obesity issue is a complex one that is influenced by endocrinology, biochemistry, neuroscience, sociology, psychology and environmental health. There are elements of personal choice involved but our choices are influenced by the choices put in front of us, the “choice architecture”, and it has been suggested that even making significant changes to this architecture is not enough (Marteau, 2011). It is clear that processed food interferes with our mechanisms of self-regulation and reward and that imbalances in hormones play a vital role in our ability to make good decisions. How we can do anything about this is another issue that involves more than personal decision making. Maybe it is “up to us” but I think that this means more than looking after ourselves, it means looking out for each other and being aware of the forces that are creating the obesogenic environment that we live in. If you enjoyed the sugar v fat documentary, or it inspired you to find out more about this area then I would recommend some of the reading below. I would particularly recommend the Lustig title as I thought it was needlessly brushed aside in the documentary. Lustig’s main points about Fructose may well be based on research in extreme diets but in his book he makes many interesting points about nutrition on both individual and societal levels and identifies the relationship between carbs and fats and how they work in partnership.

if you want to comment on this article then please do via bjane@marjon.ac.uk or @benjanefitness

References and Further Reading

BBC 2 “The men who made us fat (1/3) “ 14th June, 2012 [TV]

BBC 2 “The men who made us thin (1/4)” (1/3) 8th Aug, 2013 [TV]

Caulfield, T. (2011). The Cure for Everything!: Untangling the Twisted Messages About Health, Fitness and Happiness. Beacon Press, Boston; MA

Kahneman, D. (2011). Thinking, fast and slow. Macmillan.

Kenny, P. (2013) Is obesity an addiction Scientific American

Lustig, R (2014) Fat Chance: The Hidden Truth About Sugar, Obesity and Disease. Fourth Estate: London [amazon]

Lustig, R. (2009) Sugar: The bitter truth (a lecture) [youtube]

Marteau, T. M., Ogilvie, D., Roland, M., Suhrcke, M., & Kelly, M. P. (2011). Judging nudging: can nudging improve population health?. BMJ, 342. [full text]

Thaler, R. H., & Sunstein, C. R. (2008). Nudge: Improving decisions about health, wealth, and happiness. Yale University Press. [amazon]