"Can Cholesterol Get Too Low?"
On the standard American diet, atherosclerosis —
hardening of the arteries, the number one killer of men and women —
starts in your teens.
Investigators collected about 3,000 sets of coronary arteries and aortas —
the main artery in the body — from accident, homicide, and suicide victims,
15 to 34 years of age, and this is what they found.
The fatty streaks start in our teens, which turn into atherosclerotic plaques
in our 20s, which get worse in our 30s, and can then start killing us off.
In our heart, it can cause a heart attack.
In our brain, it can cause a stroke.
How common is this?
A hundred percent of the teens they looked at already had fatty streaks
building up inside their arteries, and by their early 30s,
most already had streaks blossoming into
atherosclerotic plaques bulging into their arteries.
This is what their aortas look like at ages 15 through 19: fatty streaks
building up throughout, but no plaques yet on average.
But the plaques start appearing in our early 20s,
and get worse in our late 20s, by which time fatty streaks
have infiltrated throughout,
and by our early 30s, our arteries are in bad shape.
But that's our aorta, the main artery that plunges down through our torso
to split off into our legs. What about the coronary arteries feeding our heart?
Same thing. We start out with fatty streaks in our teens,
begin to see the first hint of plaque in our early 20s, then late 20s,
then look at the average coronary arteries of 30 to 34-year-olds.
Most people in their early 30s already have plaques in their coronary arteries.
Atherosclerosis begins in youth.
So that's why we shouldn't wait until heart disease becomes symptomatic
to treat it. If it starts in youth, we should start treating it in youth.
It's like if you knew you had a cancerous tumor,
you wouldn't want to wait until it grew until a certain size to treat it.
Or if you had diabetes, you wouldn't want to wait
until you started going blind before you did something about it.
Okay, so how do you treat atherosclerosis?
You lower LDL cholesterol through a stringent diet that is low in cholesterol
and saturated fat, so a diet that's low in eggs, meat, dairy, and junk.
If we want to stop this epidemic, we have to alter our lifestyle accordingly,
starting as early as possible.
Is such a radical proposal totally impractical?
I mean, eating more healthfully? Radical!
It would, of course, take an all-out commitment,
but remember, this is our #1 cause of death.
I mean, if you're going to commit to anything...
We did pretty good with cigarettes, slashing smoking rates,
and lung cancer rates came right down.
And yes, healthy eating is safe.
According to the Academy of Nutrition and Dietetics,
the largest and oldest association of nutrition professionals in the world,
even strictly plant-based diets are appropriate for all stages
of the lifecycle from pregnancy, infancy, through old age.
And if you want to learn more,
the Academy can suggest a few good websites to visit.
Curing atherosclerosis should be the next major
cardiovascular prevention goal.
What evidence do we have that a life-long suppression of LDL will do it?
There's a genetic mutation of a gene called PCSK9
that about 1 in 50 African Americans are lucky to be born with
because it gives them about a 40% lower cholesterol their whole lives.
And indeed, they have dramatically lower rates
of coronary artery disease to show for it: an 88% drop in risk,
despite otherwise terrible risk factors on average.
Most had high blood pressure and were overweight,
almost a third smoked, nearly 20% had diabetes.
But that just goes to show that a lifelong history
of reduced LDL cholesterol levels
significantly lowers the risk of coronary heart disease,
even in the presence of multiple risk factors. And this near-90% drop
in events like heart attacks or sudden death occurred at an average
LDL of 100, compared to 138. So you could get even lower than 100.
Hold on! Why does the lowering of LDL cholesterol by about 40 points
in those with that lucky genetic mutation reduce heart disease incidence
by nearly 90%, whereas that same 40-point drop with statin drugs
would reduce coronary heart disease by only about 20%?
The most likely answer is duration.
When it comes to lowering LDL cholesterol,
it's not only how low, but how long it's been low.
That's why healthy lifestyle choices may wipe out like 90% of our risk
for having a heart attack, whereas drugs may reduce it by only 20 to 30%.
If you're getting treated with drugs later in life, you may have to get
your LDL under 70 to halt the progression of coronary atherosclerosis.
But if we start early enough, young enough, it may be sufficient
to just lower LDL cholesterol down to 100,
which should be attainable for most people.
That's consistent with country-by-country data that suggested heart disease
would bottom out at a population average of about 100.
But that's if you can keep it down your whole life.
If you're just using drugs late in life to try to stop
the progression of your disease, you have to get your LDL lower than 70.
And if you're trying to use drugs to reverse a lifetime
of bad food choices, you don't get to zero
until about an LDL of 55.
And if your heart disease is so bad you've already had a heart attack
but you're trying not to die from another one, ideally
you might want to push your LDL down to about 30.
Once you get that low, not only would you prevent
any new atherosclerotic plaques,
but you'd also help stabilize the plaques you already have,
so they're less likely to burst open and kill you.
Is it even safe to have cholesterol levels that low though?
In other words, can LDL cholesterol ever be too low?
We'll find out next.