I really admire Robert Lustig's clarity, his scientific background and his stand for people's health and continuing to speak out about the obesity crisis, despite mass apathy and media-driven confusion.
Here are some highlights from this excellent video:
(On whether obesity is just due to behavior)
"How do you explain obesity in six-month-olds? They don’t diet and exercise.
Obesity is occurring in countries that still have
malnutrition. This looks much more like
an exposure, than it actually does, like changing behavior.
There’s really no such thing as behavior. There’s really just biochemistry. Biochemicals change in the brain, driving
behavior.
In obesity, what is driving that behavior? I can sum that up in one word: Insulin.
Insulin does two things: Drives
energy into fat cells, thereby increasing the amount of energy stored,
therefore the obesity. But, the other
thing that Insulin does is it blocks the signal in the brain that would
normally convey satiety and signalling energy adequacy. That signal is called Leptin, and Leptin is
a hormone that’s made from your fat cells, goes to your brain and tells you
you’ve had enough. But insulin blocks
that signal. So by doing peripheral
changes which drive energy deposition and inducing central changes that drive
starvation at the level of the brain you can see how that would turn into a
vicious cycle of consumption and also disease.
So what we have learned is that Insulin is the bad guy in this story.
Q: So what can families and individuals to do change their
biochemistry, or is this not something they shouldn’t be worried about at all?
The question is, what caused the Insulin rise? If you look at studies from the 1970’s in terms of how high your insulin went in
response to a glucose challenge, maybe 50 microunits per ml. Now we’re up to 100, 150, sometimes even 250
microunits per ml (for the same test), in kids. So the question is how come kids are releasing twice or 3 times
the insulin they were before. And that
is the crux of the obesity question.
So, what’s changed during that time? Certainly our genes have not changed. But our diet has clearly changed. And, what makes insulin go up? Sugar.
But what kind of sugar.? Well,
there are three molecules that constitute the standard sugars. There’s glucose, which is absolutely essential
for life. It’s so important that if you
don’t get any, your body makes it in
order to keep your blood glucose level up.
There’s galactose, which is in milk sugar, which is immediately
converted to glucose in the liver…
And then there’s the last one -
Fructose. Fructose is the sweet part of
table sugar. It’s in sucrose. It’s in hfcs, it’s in maple syrup, it’s in
agave nectar and it’s the thing we seek, virtually every caloric sweetner, it’s the thing we like. The problem is that fructose is not glucose,
never was, never will be. Glucose is a
6 membered ring, fructose is a 5 membered ring. Glucose is regulated by insulin.
Fructose is not regulated by insulin.
Glucose goes to glycogen or liver starch in the liver for storage and
that is a non toxic storage form of energy in the liver, which is good, and
it’s what you want to make, so you have ready energy for exercise, so if you’re
glycogen depleted from either starvation or from severe exercise, you can
rebuild glycogen with fructose.
But,
what happens if you’re not. What
happens if you’re at rest… and you take in a large sugar load, say a soft drink
or a sports drink, or one of these energy drinks, which has an enormous bolus
of sugar. What happens is that the
fructose is not converted to glycogen.
It has no choice to go down to the energy mitochondria, the little
energy burning factories in the cells.
They overwhelmed, these mitochondria, and they have no choice but to
take the extra energy that’s been provided by the fructose and turn it into liver
fat. Liver fat drives all the other
chronic metabolic diseases, by inducing insulin resistance in the liver, liver
fat drives cardiovascular disease, lipid problems in the blood, hypertension,
diabetes. And possibly cancer and
dementia as well. So that’s where the
problem is. The overload of Fructose to
liver mitochondria, driving chronic metabolic disease.
....
Q: What do you recommend that the patient who is concerned
about the health risks of obesity do?
A couple of points I got from this video that hadn't occurred to me before:
1. Adding fiber to foods doesn't really work. Fiber, as it occurs naturally in food, is a combination of soluble and insoluble, and they are together that way for a reason. Watch video for more details, but basically, foods with fiber added and taking supplemental fiber is not the same as eating food with fiber intact.
2. Making a smoothie out of a fruit destroys the fiber in it. Eat the fruit, don't drink it, even as a smoothie (goes for juicing too).
