her cardiac specialists by 31 vigorous years.
As he studied medicine and specialised,
Greger became convinced Pritikin, and
later Dr Dean Ornish, who also promul-
gated a whole-plant-based diet, were on
to something. Refined foods caused lots of
problems; whole-plant-based foods could
very often solve them.
But rather than cherry-pick to confirm
his suspicions, Greger says he made a pointof looking at all the science and piecing
together his patients’ optimal strategies
from there.
He says it’s common to trace today’s
obesity boom back to the 1980s, when
nutritionists demonised fat, unwittingly
encouraging an unhealthy reliance on car-
bohydrate-dense food, with added sugar a
particular problem. But it’s not that simple,
he says.
All that “fat is the problem” advice did
not, in fact, result in a decline in Americans’
overall intake of fat. The anti-fat message
seems simply to have helped create an
implied licence to eat more low-fat food
as well. On average, Americans today eatseveral per cent more calories from fat than
in 1974 and 500 more calories a day. Given
it takes 3500 excess calories to create a
pound of fat, there’s your obesity problem.
Confoundingly, the science says the 80s
experts weren’t wrong about low-fat diets
being good. They were just right for some
not entirely right reasons.
Greger says it helps to understand that
resting metabolic rate – how many calories
we burn “just by being alive” – is the key
determinant to weight. Someone on a low-
fat diet – getting 11% of their calories from
fat – will burn more calories even in their
sleep than someone on a 58% fat diet.
All sorts of things affect metabolism, but
a key one is that fat takes the body fewer
calories to process. And because it’s so cal-
orie-dense, we can eat lots of it faster than
our body’s satiety kit can register it. With
high-chew foods such as vegetables, it gets
plenty of notice.
Even overeating on a low-fat diet gives us
a bigger calorific “free ride”, in that consider-
ably more calories travel all the way through
us unabsorbed and down the dunny. Over a
month, the non-absorbed, excreted calorie
count can save 2500 calories, compared with
the calorie wastage on a high-fat diet.MASTICATION IS GOOD FOR YOU
In the early 1900s, American food faddist
Horace Fletcher became a millionaire by
popularising chewing. “Nature will liq-
uidate/Those who don’t masticate,” hedeclared, advocating 32 chews per mouth-
ful. Many decades later, scientists confirmed
the Great Masticator, though utterly unqual-
ified, was no crank. Chewing – and eating
food that requires lots of it – helps turn on
the body’s satiety-notification hormones in
time to avert overeating.
The “cephalic” signals – from mouth
to brain – are a hugely powerful appetite-
governing rod, as a peculiar but ingenious“having your cake and not eating it” study
cited by Greger shows. One group chewed
and spat out cake for one minute, another
for eight minutes. Within each group, half
of the spitter-outers had 100 calories of
“cake solution” pumped into their stomachs
by a tube and the other half 800 calories’
worth. Half an hour later, they were all
offered a meal. Those in the long-chewing
group who had tube-ingested the smaller
number of calories ate less than the short-
chewing group that had preloaded with a
whopping 800 calories.
The cephalic phase also governs how
much of the calories we ingest are burnt, byCONQUERING THE KILOS
The body tends to
resist weight loss, but
feeding it with low-
glycemic foods seemsto blunt this trigger.
Basing your diet on
whole-plant-based foods
means you can eat lots of
food, and the transitionwill give rapid weight loss.
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