eat
MACRO
LENS
AFTER SCIENCE REVEALED
THAT CALORIES AREN’T
CREATED EQUAL,
RESEARCHERS HAVE
DISCOVERED THAT
MACRONUTRIENT SUB-
TYPES CAN CHANGE THE
WAY THE BODY RESPONDS
TO EATING.
Words: David Goding“Macronutrients are one of the tools we use to help modify body
composition,” says accredited practising dietitian Melanie McGrice
(melaniemcgrice.com.au), who specialises in weight management.
“Losing fat and gaining muscle is about getting the macronutrients
just right.” Drop your protein and carbs below a threshold and your
body will start using its own muscle for fuel, reducing metabolic rate.
Unfortunately, food labels don’t differentiate between types of
protein, carbs, fat or fibre. What happens after you’ve swallowed
a forkful of carbohydrate, protein and fat is as different as chalk
and cheese.
Once the mass of nutrients has been turned into chyme and
entered the duodenum for the gallbladder to dissolve the fats, the
pancreas douses it in enzymes that send carbohydrate, protein and fats
in different directions.
“Carbs rapidly hop onto the conveyor belt that is your
bloodstream, and several different organs take the sugar they need
as the blood passes by,” says Dr Carl Lavie, author of The Obesity
Paradox. “Some gets stored in the liver as glycogen, and whatever is
left is converted to fat and cached in fat cells,” he says.
Meanwhile, protein is broken into building blocks known as
peptides, which are further deconstructed into amino acids that can
permeate the lining of the small intestine and enter the bloodstream.
They then adopt a role building the body’s protein stores or make
their way out of the body. If energy intake exceeds the body’s needs
and excess kilojoules are in the form of protein, the surplus is stored
as body fat as with any other macronutrient – it’s just that bit harder
than storing carbs as there are more steps through which it needs to go
to convert to sugar (which is why refined carbs are deposited so darn
easily, aided by the rush of fat storage hormone insulin they cause.)
“If there’s more insulin around, there will be more LDL (bad
cholesterol) and more glucose to transport across the fat cell’s
membrane – which ultimately translates to more fat storage,”
says Dr Lavie.