Could
sugar be responsible for the obesity and diabetes epidemics?
BMJ
The idea that sugar
could be a fundamental cause of the global obesity and diabetes epidemics, with
deleterious effects on the human body that go beyond just empty calories,
should be considered seriously again, argues journalist and author Gary Taubes
in The BMJ today.
In the midst of such a
huge public health crisis, Taubes says "we must do more to discourage
consumption while we improve our understanding of sugar's role.
Doctors have long
suspected sugar is not simply a source of excess calories but a fundamental
cause of obesity and type 2 diabetes, writes Taubes. But until recently, fat
consumption and total energy balance have dominated the debate about obesity
and the nature of a healthy diet.
In 2016, World Health
Organization (WHO) director general Margaret Chan described the twin epidemics
of obesity and diabetes worldwide as a "slow-motion disaster" -- and
suggested that the likelihood of preventing the current "bad
situation" from getting "much worse" was "virtually
zero."
Why, despite all our
best efforts, have these epidemics gone unchecked, asks Taubes? A simple
explanation could be that our understanding of the cause of the disease is
flawed -- perhaps fundamentally so.
The past decade has
seen a renewed interest in the possibility that calorific sweeteners --
particularly sugar and high fructose syrups -- have major roles in causing
obesity and diabetes -- and major public health organisations are now
recommending strict limits to the consumption of these "free sugars."
But Taubes argues that
these recommendations target sugar only for its calories rather than as a
potential causal agent of disease.
What if the problem is
the sugar itself, he asks? Sugar is metabolised differently than other
carb-rich foods and could have deleterious effects on the human body
independent of its calorific content.
The evidence that
sugar has harmful qualities independent of its calories is still ambiguous,
says Taubes. "If it is true, though, it changes how we must communicate
the dangers of sugar consumption."
Setting an upper limit
to the amount of sugar that should be consumed in a healthy diet is a good
start, "but we don't know if the level recommended is safe for
everyone," he warns.
"It could be that for people who have obesity or
diabetes, or both, even a little is too much. And the ubiquity of sugar rich
products may make it difficult for many people to maintain a healthy level of
sugar consumption."
Given the scale of the
obesity and diabetes epidemics, "then a concerted programme of research to
establish reliable knowledge on this subject should be among our highest
priorities," he concludes. "Meanwhile, we can acknowledge the
uncertainties while still recommending strongly against consumption."
