nosh magazine
SHOULD
YOU GO
LOW CARB?
Low carb diets have been around since the 1960s, with the best known approach
being the Dr Atkins diet. It lost popularity to low fat diets over the last few
decades, but as nations have continued to get fatter and the major flaws of going
low fat have been exposed, the low carb approach is once again gaining
momentum. Dr Joanna McMillan explores the question, “should you go low
here are now several good clinical
trials showing that the approach can
be effective and safe, with some studies
showing better results when compared to a
low fat diet. But does that mean it’s the way
we should all be going? I don’t believe so.
Here’s why:
T
1. The studies almost
always compare low carb to
low fat, but these are not
the only options.
Why not compare a low carb diet to one
with moderate carbs and moderate fat,
from good quality food sources? There are
many ways to put together a healthy diet to
help us to control our appetite and eat less,
while still enjoying our food. My second
question is what exactly is meant by “low
fat”? We now understand that replacing fat
with lots of refined carbohydrate (e.g. low
fat cookies and ice cream) does not benefit
our health. But a low fat diet based on
whole foods (e.g. the traditional Japanese
diet) and is likely to create a very different
picture. Also, when you look closely at the
data you’ll see some people did better on
low fat, while others did better on low carb,
which suggests something else is at play
– genetics or perhaps personal food
preferences that allowed better adherence
to one diet or the other.
2. We have to look at what
replaces the carbohydrate
or the fat.
Low carb diets usually have a high protein
content, but also a high fat content. But
where is the fat coming from? Is it high in
saturated fats, or high in plant fats, which
are mostly unsaturated? A low fat diet can
also be high in protein, but keeps the good
quality carb-rich foods in there too. All of
these diets are very different and may have
different effects on our health and weight
control. Certainly many of the high protein
diet studies actually have moderate
amounts of carbohydrate, suggesting that
the benefits are due to the extra protein
rather than from avoiding carbs.
3. Going low carb can make
it difficult to meet your fibre
requirements.
Wholegrains, legumes and fruit are also
major contributors to fibre and without
them you have to eat an awful lot of veggies,
nuts and seeds to meet your daily target.
You can do it if you’re very dedicated to
packing your meals with veggies, but since
only seven per cent of Aussies are managing
to eat the recommended five serves a day, it’s
a pretty big challenge to successfully eat
more. Cereal fibre also seems to play a
particular role in gut health, as does
resistant starch found in beans, firm
bananas and cooked and cooled potatoes,
pasta and rice. This special type of fibre
feeds the good bacteria in your gut, with
many knock on health effects. Furthermore
large population studies have shown that
those who eat wholegrains tend to be leaner
with smaller waist measurements. Lumping
these “smart carbs” in with all carbcontaining foods is just nutritional
nonsense.
4. Carbohydrates are the
premium fuel for the brain
and for powering exercise.
The more intense the exercise, the more
carbohydrate we need to use. Fat provides a
slow steady stream of energy but cannot be
burned quickly enough for more strenuous
exercise. Low carb diets can, therefore, make
it very difficult to exercise at any intensity.
You may also find your brain feels a little
foggy and concentration is more difficult.
Perhaps this abates if you stick with the plan
and your brain adjusts to using ketone bodies
– made from fat – but why deprive your
brain of the fuel that works best?
Of course, probably the most important
point is that most people find low carb
diets really difficult to stick to in the long
run. And at the end of the day, regardless
of how effective a diet is, if you can’t
follow it for the long term it’s not going to
do you much good. I certainly don’t
dismiss this diet completely as it will be
right for some of you, but for the majority
I prefer a more balanced approach, based
on quality food. N
Dr Joanna McMillan, PhD APD
Learn more about Dr Joanna at website | profile
Adopted by the nation as an honorary Aussie, Dr Joanna McMillan’s ever-growing following is the
result of her high profile within the media, health and fitness industries, and through her roles as
Vice President of the Australian Lifestyle Medicine Association (ALMA), Ambassador for Diabetes
Australia, and Ambassador for Australian Pineapples (to name a few).
www.n4foodandhealth.com
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