By vegan naturopath Robyn Chuter.
In a previous post, I summarised the answer I gave to an EmpowerEd member, during a live Ask Robyn session, about the 5:2 diet. Another question from that session was about Sweet Poison by David Gillespie, one of a slew of books and documentaries that has come out in the last decade or so, blaming increased consumption of sugar for the epidemic of obesity and diabetes in Westernised countries.
I wanted to give you a taste of what you’re missing out on if you’re not already an EmpowerEd member, so here’s a summary of the answer I gave to the question:
First up, let me point out that David Gillespie is a lawyer by training and has no qualifications in nutrition. He claims that having legal training equips him to see flaws in arguments, and I know from the personal experience of being married to a (now ex-) lawyer that this can be true. The problem is that Gillespie’s complete lack of knowledge of basic human and nutritional biochemistry, not to mention the scientific process – he admits in the introduction to Sweet Poison that he almost failed biology and chemistry in high school, and boy, does it show – makes him prone to being sucked in popular theories that just don’t fit with the facts.
His books have almost no references, and when he does cite sources, he’s highly selective (two hallmarks of pseudoscience, as I discuss in detail in my Empowered Eating seminar). A few examples:
In the introduction to Sweet Poison, he describes how his quest to discover the ‘truth’ about sugar was set in motion by the 1966 book The Saccharine Disease, written by a British navy doctor, which blamed “the highly processed sugar and refined flour diet of the twentieth century” for the epidemic of obesity, diabetes and heart disease which was in its early days back then.
The problem with this argument is that, as Michael Pollan pointed out in In Defense of Food, a reduction in the sugar tax in 1874 led to a massive increase in sugar consumption in England, since poor people could now afford what had historically been a luxury food for the rich. By the end of the 19th century, sugar comprised one-sixth of total energy intake, which is similar to current intake levels in western nations… but there was no accompanying increase in rates of obesity, heart disease or diabetes, rates of which did not begin to rise until decades later. If fructose (which along with glucose, forms sucrose or table sugar) is the deadly poison that Gillespie claims it is, why weren’t those Brits getting sick from it?
Gillespie repeatedly claims that fructose is the major cause of obesity, heart disease and type 2 diabetes. But a 2010 review of the published scientific literature found
“no evidence which shows that the consumption of fructose at normal levels of intake causes biologically relevant changes in triglycerides (TG) or body weight in overweight or obese individuals.”
“Isocaloric exchange of fructose for other carbohydrate improves long-term glycemic control, as assessed by glycated blood proteins, without affecting insulin in people with diabetes.”
In other words, swapping an equal calorie amount of fructose for other sugars actually improves blood sugar control in diabetics.
And most recently, a 2016 review of recent randomised controlled trials and prospective cohort studies (the two forms of studies considered to produce the highest-quality evidence in nutrition research) concluded
“normal added sugars in the human diet (for example, sucrose, high-fructose corn syrup and isoglucose) when consumed within the normal range of normal human consumption or substituted isoenergetically for other carbohydrates, do not appear to cause a unique risk of obesity, diabetes or cardiovascular disease.”
He repeatedly ignores easy-to-obtain Australian data on sugar consumption because they don’t fit his hypotheses, in favour of overseas data which do. Comparison of food consumption data and obesity rates in Australia, the UK, Japan and the US found that fructose consumption has declined in Australia, the UK and Japan while obesity prevalence has increased, and
“unlike the USA, total fructose consumption is inversely associated with overweight/obesity in Australia, the UK and Japan since the early 1970s.”
Or, in plain English, the more fructose people eat (at least in Australia, the UK and Japan), the thinner they seem to be.
Gillespie also claims that
“every gram of fructose we eat is directly converted to fat”.
This is completely incorrect—every first-year nutrition student learns that fructose may either be converted to glucose (gluconeogenesis) and be converted into glycogen for storage, or be converted into fat (fructolysis). Evidence suggests fructose is preferentially converted to glycogen until liver glycogen (the storage form of carbohydrate in animals’ bodies) is replenished; only then will the fructolytic pathway predominate.
One of his most ludicrous statements is that
“The metric equivalent of the calorie is a joule, and calculated using Einstein’s famous equation E=mc2 …” (p. 203 of Sweet Poison).
ROFL!!! Einstein’s equation for the special theory of relativity has precisely diddly-squat to do with calories or joules. A joule is the basic SI unit of energy (and also of work), and is defined as the energy transformed (or work conducted) when a mass of one kilogram is accelerated at one metre-per-second-squared over a distance of one metre.
The moral of the story:
Don’t buy into pseudoscientific claptrap about diet, written by a person with no education in the subject!
Now, to be perfectly clear, I’m by no means telling you to go out and eat sugar. Refined sugar is devoid of the fibre, vitamins, minerals and phytochemicals that the whole sugar cane or sugar beet contains. Eating sugar, or any other natural or artificial sweetener, distorts your palate and displaces nutrient-dense food that you should be consuming instead.
My point is that the search for a single dietary scapegoat that we can blame for all our woes is just plain stupid. Dietary patterns make the difference between health and disease, not the inclusion of some so-called ‘superfood’, or the the exclusion of some individual ‘villain’.
I advise my clients to avoid sugar and all other sweeteners – yes, that includes agave, honey, and all the fancy-schmancy sugars – with just two exceptions: date sugar and organic blackstrap molasses. Instead of using dextrose (the most common form of glucose) as Gillespie incomprehensibly suggests, just learn to appreciate the natural sweetness found in fruits and starchy vegetables. My personal experience – backed up by virtually all of my clients – is that cravings for sweet foods diminish quite rapidly when you eat a high-nutrient diet of vegetables, fruits, legumes and whole grains. In fact, nowadays I can’t stand the sweet cakes, slices and biscuits I used to love; they’re too cloying for me.