Life insurance companies know a surprising secret about
cholesterol that most doctors never tell patients: When it comes to rating your
risk for a fatal heart attack, the least important cholesterol
number is your level of LDL (bad) cholesterol. In fact, life insurance
actuaries don’t even look at LDL levels, because large studies show it’s
the worst predictor of heart attack risk.
Instead, life insurance companies use a simple math formula to
rate your heart attack risk: They divide your total cholesterol by the level of
HDL (good) cholesterol.
“If the ratio is below three, and there’s no inflammation in
your arteries, you’re practically bulletproof against heart attacks and
strokes, even if your LDL is high,” reports Amy Doneen, MSN, ARNP, medical
director of the Heart Attack & Stroke Prevention Center in Spokane,
Washington.
Here’s a look at eight common cholesterol myths.
Myth: Cholesterol is inherently evil.
Fact: You couldn’t survive without cholesterol, since this waxy
substance produced by the liver plays many essential roles in our body, from
waterproofing cell membranes to helping produce vitamin D, bile acids that help
you digest fat, and sex hormones, including testosterone, estrogen, and
progesterone.
Cholesterol is ferried through your body by molecular
“submarines” called lipoproteins, such as low-density lipoprotein (LDL) and
high-density lipoprotein (HDL).
Myth: Low cholesterol is always a
sign of good health.
Fact: Although low levels of LDL cholesterol are usually
healthy, a new studyreports that
people who develop cancer typically have lower LDL in the years prior to
diagnosis than those who don’t get cancer.
Researchers compared 201 cancer patients to 402 control patients
without cancer, matched by such factors as age, gender, smoking, blood
pressure, diabetes, and body mass index. None of the patients had taken
statins.
Thirteen earlier randomized clinical trials of statin therapy
also found a link between low LDL and cancer, causing medical debate about
whether statins raise risk. The new study suggests that an unknown biological
mechanism—rather than cholesterol-lowering medication—may be the culprit.
Myth: High LDL means you could be
headed for a heart attack.
Fact: Nearly 75 percent of people hospitalized for a heart
attack have LDL (bad) cholesterol levels that fall within current recommended
targets, and close to half have “optimal” levels, according to a national study of
about 136,000 people. The researchers also reported that levels of protective
HDL (good) cholesterol have dropped in heart attack patients over the last
several years, probably due to the rise in obesity, diabetes, and insulin
resistance. Only 2 percent of the patients studied had ideal levels of both LDL
and HDL.
Myth: All LDL particles are equally
dangerous.
Fact: The size of the particles matters, says Doneen. “Think of
beach balls and bullets. Some LDL particles are small and dense, making it
easier for them to penetrate the arterial lining and form plaque, while others
are big and fluffy, so they tend to bounce off the artery walls.”
People who mostly have small, dense LDL cholesterol are up to
three times more likely to have heart attacks than those with big, fluffy
particles.
Myth: Americans have the world’s
highest cholesterol levels.
Fact: Contrary to the stereotype that most of us are just a few
big Macs away from a heart attack, US men rank 83rd in the
world in average total cholesterol and US women 81st, according to
the World Health Organization. For both sexes, the average is 197 mg/dL,
slightly below the borderline high range (200
to 239 mg/dL).
In Colombia, men average a whopping 244 mg/dL—a level that
doubles heart-disease risk—while Israeli, Libyan, Norwegian, and Uruguayan
women are in a four-way tie for the highest average with 232.
Myth: Triglycerides trigger heart
disease.
Fact: “Triglycerides, a type of blood fat, don’t invade the
artery wall and form plaque,” explains Doneen. “However, high triglycerides mark
another huge problem: insulin resistance, a pre-diabetic condition that is the
root cause of 70 percent of heart attacks.”
High triglycerides are also one of the warning signs of metabolic syndrome, a cluster of abnormalities
that multiply risk for coronary artery disease, stroke, and type 2 diabetes. To
be diagnosed with metabolic syndrome, you must have three or more of these
disorders: high blood pressure, high blood sugar, a large waist, high
triglycerides, and low HDL.
Myth: Eggs clogs up arteries.
Fact: It’s true that eggs are high in dietary cholesterol, with
upwards of 200 mg, mainly in the yolk. Research shows, however,
that eating three or more eggs a day boosts blood concentrations of both good
and bad cholesterol.
The LDL particles tend to be the light, fluffy ones that are
least likely to enter the arterial wall, while the increased HDL helps keep the
arteries clean, suggesting that most people’s bodies handle cholesterol from
eggs in a way that’s unlikely to harm the heart. The researchers say that their
findings add to growing evidence that eggs are not “a dietary
evil.”
Myth: There are no visible symptoms
of high cholesterol.
Fact: Some people with high cholesterol develop yellowish-red
bumps called xanthomas that can occur on the eyelids, joints, hands, or other
parts of the body. People with diabetes or an inherited condition called
familial hypercholesterolemia are more likely to have xanthomas.
The best way to tell if your cholesterol is too high is to have
it checked every three years, starting at age 20, or more often, if advised by
your healthcare provider.
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