In trying
to maintain a healthy weight I needed to unlearn many of the myths surrounding
food and dieting.
A CALORIE
IS NOT A CALORIE
I used to
believe that the number of calories I ate were the key to weight gain. I believed
the myth that calories in and calories out accounted for all weight changes.
This was very frustrating for me because I just couldn’t seem to eat small
enough portions to lose weight. Also, eating these small portions left me very
hungry and unsatisfied.
Eventually
a doctor I consulted recommended a low carbohydrate diet and suddenly I started
to shed my excess weight without difficulty. What I came to learn is that
contrary to popular belief, calories are NOT the only thing you need to concern
yourself with when it comes to losing weight. Research over the last 20 years
has made remarkable progress in understanding adipose tissue (body fat cells)
and how we gain and lose weight. Calories have very little to do with this process.
Some calories (carbohydrates and sugar) can turn straight to excess body fat
and some simply cannot.
EATING
FAT DOESN’T MAKE YOU FAT
We’ve
probably all heard the saying “you are what you eat,” but that doesn’t mean
that when we eat fat, we get fat. This is perhaps one of the biggest and most
misunderstood aspects of diet. The most important lesson about fat and dieting is that without sugar or carbohydrates,
even a diet that is high in fat simply CANNOT make you gain weight.
In fact, there
are many benefits to eating fat for weight loss. Not only is fat necessary to
the flavor of food, it also leads to feeling satiated and full after a meal. Obviously,
it is much easier to lose weight if you feel satisfied after meals.
As evidence
that eating less fat does not lead to weight loss, in the last 50 years or so, dietary
fat consumption has been reduced dramatically in the United States while
carbohydrate (especially sugar) consumption has skyrocketed. If a low-fat diet
really helped with weight loss, then we should have seen a reduction in obesity
rates. In fact, we see the exact opposite...a massive unprecedented increase in
obesity, insulin resistance, and diabetes.
THE TRUTH ABOUT WEIGHT GAIN
- EXCESS CARBS = EXCESS BODY FAT
The fat
that forms in your body has very little to do with the fat that you eat, but a
lot to do with how much glucose that you eat from sugar and carbohydrates. When
you eat carbohydrates, it is broken down into glucose. Some of this glucose will
be used immediately for energy but any excess will be joined with the fatty
acids from the fat that you eat to create fat cells. Body fat is simply a way for your body to store excess glucose so
that it can be used later (e.g. during sleep or times of famine).
The
mechanism for this is that carbohydrates trigger insulin to be released.
Insulin then binds excess glucose from carbohydrates to fatty acids, turning
this combination into fat cells. The key here is that fatty acids (from “fat” in food) alone DO NOT get stored as body
fat. In fact,
in the absence of carbohydrates, any excess fat is simply flushed out in our
stool.
FAT IS
ESSENTIAL FOR HEATH
A very
important thing to understand is that eating healthy fat is critical to
everyone’s health. When we eat fat, it breaks down into fatty acids which are
then absorbed into our body. Some of these fatty acids are “essential”, meaning
that we can only get them from our diet and our body cannot make them in any
other way. Essential fatty acids are used throughout our bodies for many
purposes (including brain function).
Also, in
the absence of glucose in our bloodstream, fatty acids are used to create
energy for muscles and many other body systems. Low fat or non-fat diets are
not only virtually meaningless for weight loss, but they can also be dangerous
in the long term as you are deprived of essential fatty acids that are critical
to every system in your body.
Another
thing to consider in trying to lose weight is that different sources of
calories require very different amounts of energy in your digestive system to
fully break them down. Protein takes a lot more energy (both heat and chemical
energy) to break down and a relatively large amount of time to absorb in the
gut than does sugar. Sugar/carbohydrates break down to glucose and is absorbed
pretty much “as is”, providing a large amount of energy at almost no digestive
cost (since almost every cell can use glucose directly for energy). Fats take
even longer to digest than protein or sugar. If you want to lose weight, you
want to make the body work for its calories. Fat and protein are the best choices,
while carbs are not.
NOT ALL
CARBS ARE EQUAL
Eating some
carbs are essential to good health. For example, vegetables and fruit are
carbohydrates. There are many healthy molecules in fruits and vegetables that
contribute to overall health.
The key
for weight loss is to eat the carbohydrates that have the lowest ability to
raise glucose levels (the lowest glycemic index). This includes foods that are
the least sweet, for example green vegetables.
I like to
explain that the foods that will turn into a new plant (grains, legumes and
tubers like potatoes) have the greatest density of carbohydrates stored as energy
to create a new plant. However, foods like green vegetables have already
expended this energy and so have a lower carbohydrate content.
To lose
weight, eat the carbs that have the lowest glycemic index. Foods that have a
low glycemic index raise insulin far less than foods that have a high glycemic
index. This prevents weight gain and obesity.
WEIGHT LOSS and CRAVINGS
As we discussed, carbohydrates (a.k.a. sugar) get turned into fat
pretty easily when eaten in excess. So, regulating carbohydrate intake is the
best way you can control levels of body fat. If you were to eat almost no carbohydrates,
your body would use up its stores of sugar (glucose and glycogen) pretty
quickly and start to dip into its fat reserves for energy. Fat is then “burned”
(split apart) for the sugar locked inside and used as the primary source of
energy.
The brain uses glucose when it is available, but once that runs
out, it switches to using protein for energy by making and using molecules
called “ketones”. So, in the absence of carbohydrates (and sugar), your body
will simply use fat and protein for energy. There is nothing wrong with this,
and our ancestors ate diets rich in protein and fat (from animals) before (and
after) the invention of agriculture.
Finally, if you suffer from cravings for carbohydrates and sweet
things, the best way to end the cravings is to eliminate all carbs from your
diet for about 3-5 days. Your body will switch its metabolism over to using
ketones and fat, and your carb cravings will start to resolve.
RATIOS
Getting the right ratios of protein, fat, and carbohydrates in
your diet goes a long way toward reaching and maintaining weight goals. Since
the levels of carbohydrates necessary for weight control vary between
individuals, there is no real blanket recommendation I can make other than to
“eat fewer grams of carbs for weight loss” and “increase slowly to find a level
of weight maintenance”. Don’t be afraid
of eating fat; remember, it won’t make you gain weight.
CONCLUSION
It bears
repeating again that the amount of fat you eat has absolutely no bearing on
the storage of fat in your body. Fat is a healthy part of our diet and
provides us with the fatty acids we require to maintain health and vitality. In
the absence of carbohydrates, our bodies use the glucose stored in fat cells
(and then the fatty acids stored with it) as energy and you lose weight by
“burning” body fat which ultimately leads to weight loss. A healthy diet incorporates
the right proportion of protein, fat and carbohydrates that reverses obesity and
helps maintain a healthy weight.
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.