Cholesterol Myths that May Surprise You
By Lisa Collier Cool
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 study reports
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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By Lisa Collier Cool
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