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Vaccines can cause autism.
Myth! Some people have
raised concerns that substances used
in trace amounts in certain vaccines—
including formaldehyde, aluminum
salts, and thimerosal, a mercury-
based preservative—could cause au-
tism. But none of these substances
has been shown to cause harm in the
small doses used in vaccines. Nor is
there any evidence that multiple or
combination vaccinations, such as
those recommended for children,
can weaken the immune system and
trigger autism, as some people fear.39
Women should be as
worried about colorectal
cancer as men are.
Truth! Colorectal cancer is the third
most common type of cancer among
men but the second most common
for women. Men do have a slightly
higher risk overall: About 1 in 22
men will develop colorectal cancer,
compared with 1 in 24 women.40
Caffeine is good for hearts.
Truth! It might seem as if
anything that makes your heart race
would put stress on your ticker, but
mounting evidence says just the op-
posite. Studies suggest that drinking
three cups of coffee a day is linked
to a lower risk of cardiovascular
problems. The antioxidants in coffee
may play a role, and caffeine might
speed up cellular processes that
help repair the heart.41
A workout won’t counteract
the effects of sitting all day.
Truth! A study of almost 8,000
adults found that people who sat the
longest overall and for the longest
uninterrupted time had the greatest
risk for death, regardless of whether
they’d squeezed in a workout. That’s
not to say exercise is useless, but
it’s important to scatter activity
throughout the day in addition to
a designated workout.42
Poison ivy is contagious.
Myth! The only way to
develop a rash is to come in contact
with the plant or its sap yourself. You
cannot catch the itch from someone
else—as long as that person washed
the sap off.43
Sitting too close to the
TV damages your eyes.
Myth! Until the late 1960s, the
amount of radiation coming from
TVs wasn’t well regulated, so some
people worried that sitting too close
could cause health problems. Mod-
ern TVs don’t pose that risk. Staring
at anything for a long time can make
the eyes feel tired, but it won’t do
permanent damage.44
Probiotics can help
ease diarrhea.
Truth! While studies haven’t pinned
down which “good” bacteria, yeast
strains, and doses are most helpful
against diarrhea, the research isrd.com 77Cover Story Reader’s Digest