Carbohydrates are, in
fact, not quite the same as eating lumps of fresh lard as the media
would like you to believe. Influential phrases such as 'NO CARBS
BEFORE MARBS' are gleefully preached as if going near a source of
carbohydrates will instantly cause you to gain fat. Now I don't know
many people who don't love carbs, but I do know many people who would
love to just eat them and diet. The problem is they're stuck in the
thought that eating carbs and losing weight are like separate
dimensions. While I've gone over this quite in depth in the IIFYM
blogs (read them before this one if you haven't), people I've spoken
to about this still appear to be overly confused by carbohydrates and
their general purpose/role in the body. Here are 4 incredibly common
myths.
MYTH 1 –
CARBOHYDRATES MAKE YOU FAT
SOURCE – NO CARBS
BEFORE MARBS AND VARIOUS OTHER CELBRITY/MAGAZINE STUPIDITY
Lets take a brief look
again at the metabolism of carbohydrates (1) -
- You eat them, they're tasty, you wonder why on earth you stopped eating them.
- Digestion begins in the mouth and they get broken down further in the stomach.
- In the small intestine they get broken down into glucose/galactose/monosaccharides and then absorbed directly into the bloodstream.
- The pancreas is informed that the blood sugar levels have risen and releases insulin*
- Insulin transports the glucose to the cells that require it (mostly muscular cells)/liver.
Now where in this chain
of events do you see 'HOLY SHIT I'VE EATEN A CARBOHYDRATE BETTER GET
A NEW WARDROBE AND PREPARE FOR OBESITY TO SET IN'. Wait, you don't.
For de novo lipogenesis (conversion of carbohydrates to fat), you
must consume so many carbohydrates you become completely saturated
with glycogen, this is actually quite a rare thing to happen.
Lets look at it in a
metaphorical way, your glycogen stores can be seen as a bucket -
This is where people
begin to believe the no carb dietary myths simply because their
inactivity is causing their muscular stores (80% of the bucket) to be
untouched. They are untouched because the body prefers to use fatty
acids as fuel when in a state of inactive/low activity (2).
Consequently you're not going to gain bodyfat eating any type of
carbohydrates unless you go on some truly excessive binge or do no
exercise.
CONCLUSION – IT
TAKES A LOT MORE THAN JUST EATING TO STORE CARBS AS FAT
*Insulin is often cited
as the fat storage hormone, it's main purpose is transporting
glucose. What it does do is inhibits glucagon and the resulting
lipolysis (breakdown of fat) until blood sugar levels return to
normal. Insulin is not a fat storage hormone in times of normal
carbohydrate consumption as you are led to believe, it is a transport
hormone.
MYTH 2 – YOU CAN
ONLY EAT LOW GI FOODS OR YOU'LL GET FAT/DIABETES
SOURCE – FOOD
COMPANIES
So now you know you
won't gain any weight with carbohydrates, lets dispel the thought
that eating a diet of wholemeal bread and fruit is healthy whereas
haribo and white bread will cause rapid fat gain. This is down to the
glycemic index (GI, 3) and the erroneous way it has been pushed to
the public by the media. Here are my issues with it -
- The GI index of foods was worked out in a study using fasted subjects and using pure carbohydrate sources. I don't know anyone who eats a diet of 100% carbohydrate sources while fasted. As soon as fat/protein or even food that's still digesting enters the equation, it completely changes the glycemic response (blood sugar levels) to eating said foods. This alone completely discredits the GI scale.
- The GI index does not take into account quantities at all. If you think eating 5 bananas (110g of carbohydrates roughly) is going to have a lesser glycemic load on the body than eating a packet of fruit gums (40g of carbohydrates) because of the scale saying they aren't absorbed as quickly, then you have been misinformed.
- The human body itself is incredibly sensitive to small changes in blood sugar and will regulate it very fast and efficiently with insulin and glucagon.
The conclusion of this
being that the science behind carbohydrate metabolism does NOT
support the notion that eating 'bad' carbs will make you gain fat any
more so than 'good' carbs, nor does it support the notion that rapid
increases in blood sugar will happen by eating faster absorbing
carbs. Because to be quite honest, unless you're eating a diet
consisting of 100% carbohydrates, you're not going to notice any
difference between white refined bread and brown wholemeal bread for
example, other than the mineral/fibre intake.
CONCLUSION – A
CARB IS A CARB, 1G=4KCAL REGARDLESS
MYTH 3 – NO CARBS
BEFORE BED
SOURCE –
MAGAZINES/SUPPLEMENT COMPANIES
Your
metabolism does not change into a fat storage machine over night. The
processes are the same, the rumours are pushed by companies/magazines
to sell various products that promise to repartition the nutrients.
If your 'bucket' is not full when you go to sleep it's not going to
suddenly overflow, to test this theory, please purchase a bucket, put
some water in it and then tell me if it somehow overflows while
you're sleeping.
CONCLUSION – YOUR
BUCKET WON'T OVERFLOW
MYTH 4 – MY
METABOLISM IS SLOW I CAN'T EAT CARBS
SOURCE – OBESE
PEOPLE TALKING RUBBISH/BLAMING GENETICS
Leptin
is a hormone and like most hormones it is governed by homeostasis.
The body wants to keep body fat at an optimal set point, not shredded
with striated deltoids and most certainly not obese.
This
is where leptin comes in. Leptin is produced in fat cells, so
essentially the more body fat you have, the higher your leptin levels
will be and the lower your appetite should
be. This is also a reason why woman generally eat less than men
because of naturally higher fat levels.
The
issue here is that chronically obese people have so much leptin that
they become leptin resistant, resulting in eating ridiculous amounts
of food to feel 'full' and just worsening the problem. The other side
to this is ridiculously lean individuals such as a competitive
bodybuilder after a show having an insatiable appetite. This is
because the body attempts to restore itself to a homeostatic amount
of body fat, this is not ripped with striated deltoids, nor is it
obese with several chins. The body actively attempts to prevent this
happening with the hormone leptin.
What
people like to say however, is that they got obese because of eating
carbohydrates and having a slow metabolism due to genetics.
If
this was a photo, that may be true. The reason people get obese and
end up in the leptin resistant hole in the first place is down to
poor dietary choices combined with disproportionate amounts of diety
fat (basically over consuming food). Often combined with lack of
activity.
Another
note to make on the subject of leptin, low carb dieting (4) tends to
reduce the short term output in Leptin which can lead to large
amounts of hunger. This is why refeeds and carb cycling tend to be
popular at lower levels of body fat (<10%). It's also why large
uncontrolled binges tend to happen on low carbohydrate diets, even
more so when alcohol is involved and the impulse to eat an entire
loaf of bread at the end of the night overcomes logical thinking and
leads to a bit of fat gain.
CONCLUSION – YOU
ARE OVERWEIGHT BECAUSE YOU EAT TOO MUCH, NOT BECAUSE 'GENETICS', YOUR METABOLIC 'DISORDER' IS MORE THAN LIKELY A BYPRODUCT OF YOUR WEIGHT
A
short anecdote of my own experience of carbs and dieting is that I
was able to drop about 70lb, from an obese state, to under 10%
bodyfat without the exclusion of any carbohydrates at any point in my
transformation. The last stages of the dieting phase were full of
wonderful cheesecakes, chocolate and various other things that one
would just simply not think to include on a diet. How? IIFYM!
To conclude, the thing
that matters the most is ENERGY BALANCE (calories in<calories
out). If your bucket overflows,
it will spill into fat storage. If not, enjoy your tastier new way of
eating.
1. Self Nutrition Data
(2012) Glycemic Index [Online].
Available at: http://nutritiondata.self.com/topics/glycemic-index
2. Ripptoe, M. and
Kilgore, L. (2010) Practical Programming for Strength Training.
2nd
Edn. Aasgard Company
3. Raw Food Explained
(2012) How Carbohydrates are Digest and used by the body
[Online]. Available at:
http://www.rawfoodexplained.com/carbohydrates/how-carbohydrates-are-digested-and-used-by-the-body.html
4. Pubmed (2000)
Twenty-four-hour leptin levels respond to cumulative short-term
energy imbalance and predict subsequent intake. [Online].
Available at: http://www.ncbi.nlm.nih.gov/pubmed/10946866
5. Pubmed (1997) Effect
of fasting, refeeding, and dietary fat restriction on plasma leptin
levels.[Online]. Available at:
http://www.ncbi.nlm.nih.gov/pubmed/9024254
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