DO CALORIES
REALLY
MATTER?
A new model of obesity suggests that when it comes to weight
management, quantity of calories consumed is not as important as
ensuring that every calorie promotes optimum hormonal balance.
WORDS: MATT O’NEILL
hy do some people fail to lose
weight despite cutting calories
and boosting exercise? And why
do others appear to eat an unlimited quantity
of food without gaining a kilo? New research
is now questioning whether calories really
matter and pointing towards a different
dietary approach to achieve lasting results.
W
For years the theory has been that if you
consume more calories than you expend,
you’ll gain weight, and if you then become
obese you may be at a higher risk of
metabolic defects like type II diabetes. Now,
in 2014, US academic weight loss gurus
professors David Ludwig and Mark Friedman
have published a new model of obesity
in the Journal of the American Medical
Association (Ludwig, D.S. and Friedman,
M.I. Increasing adiposity – Consequence
or cause of overeating? JAMA. E1-2; May
16, 2014). Interpreted simply, they say that
it’s our metabolic chemistry and hormones
that get mucked up first and then weight
gain follows, not the other way around. Let’s
break that down.
How we really get fat
The professors say that overeating,
particularly of sugars and high-glycaemic
index (GI) complex carbohydrates like
white bread, trigger an increase in blood
insulin level. Insulin’s job is to clear the
blood of sugars and fats and get these
macronutrients into storage in muscles and
fat cells. Insulin generally does this well,
leaving lower levels of sugars and fats in the
bloodstream. According to this new model
of obesity, the drop in circulating metabolic
48 | NETWORK SUMMER 2014
fuels in the bloodstream provokes hunger
and increased food intake.
A vicious cycle emerges, in which
overeating stimulates insulin production. The
ensuing cravings cause more overeating,
even more insulin and then eating again. A
drop in circulating metabolic fuels may also
act to reduce resting metabolic rate and the
energy cost of moving muscles. So, calorie
burning drops off too.
The concern is that this can be happening
when someone is at a normal weight, and
well before they realise a change in eating
behaviour is required to avoid future weight
gain and metabolic complications.
The problem with cutting calories
The almost universal approach to counter
weight gain has been to create an energy
deficit, whereby you eat fewer calories than
you expend. But dieting can exacerbate the
biochemical dysfunction by further limiting
the shortfall in metabolic fuel availability in
the bloodstream.
Restrictive diets also set off a series
of other compensatory mechanisms that
defend an individual’s current weight.
Energy expenditure decreases due to a drop
in resting metabolic rate as the body seeks
to conserve energy. Hunger levels also
increase as your body attempts to get back
denied dietary calories.
This explains why so many diets are
doomed to fail. Your body fights back
to restore the balance. And it looks like
hormones are at the centre of how it all works.
A focus on diet composition, not
calories
Ludwig and Friedman say a focus on dietary
quality over quantity is required to improve
metabolic function. Their approach aims to
reduce insulin release with a low-glycaemic
index or low-carbohydrate diet, while not