15 Myths and Surprising Facts About Your Heart!
Confused by the news about heart health? Drs. Marc Gillinov and Steven Nissen,
top heart docs at Cleveland Clinic, the nation’s #1 heart hospital,
aren’t surprised. As they write in the opening of their new book, Heart 411: The Only Guide to Heart Health You’ll Ever Need,
“Weekly health headlines skim the surface of the medical ocean — take
fish oil, pass on heart scans, throw away your aspirin — but what do the
studies really say? What is the message for you and your heart? We
decided to explore the science behind the headlines and to explain
clearly but completely the evidence supporting our plan for your heart
health.” Here, they tackle 15 claims to help you get to the heart of the
matter.
The Claim: Going to the Doc Can Raise Your Blood Pressure
The Truth: For
many of us, a visit to the doctor causes emotional stress, and your body
releases adrenaline and other hormones into your bloodstream,
increasing blood pressure. We call this doctor-induced increase in blood
pressure “white coat hypertension.”
If your doctor determines that you have high blood pressure, make sure that this is not simply white coat hypertension. Buy your own blood pressure monitor and check your pressure at home under less stressful conditions. If your resting blood pressure at home is normal (120/80 or less), you have white coat hypertension. If you have white coat hypertension, however, stay on top of your blood pressure (frequent blood pressure checks, exercise, good diet) to limit your chance of developing real hypertension in the future.
If your doctor determines that you have high blood pressure, make sure that this is not simply white coat hypertension. Buy your own blood pressure monitor and check your pressure at home under less stressful conditions. If your resting blood pressure at home is normal (120/80 or less), you have white coat hypertension. If you have white coat hypertension, however, stay on top of your blood pressure (frequent blood pressure checks, exercise, good diet) to limit your chance of developing real hypertension in the future.
The Claim: Red Meat Is Black-Listed
The Truth: Red
meat is relatively high in saturated fat, and as a result, it gets a bad
rap. The most important point is to distinguish between processed and
unprocessed products. Compared to unprocessed meats, processed meats
have similar contents of saturated fat and cholesterol. The key
difference is that they have four times as much sodium and 50 percent
more nitrates and nitrites. The sodium can increase blood pressure,
while the nitrates may promote atherosclerosis and diabetes.
In general, limit all red meats because of their high saturated fat content and try to avoid processed red meats. An occasional meal that contains a reasonable quantity of unprocessed red meat (a 6- to 8-ounce steak, not a 22-ounce rib eye) is unlikely to cause harm.
In general, limit all red meats because of their high saturated fat content and try to avoid processed red meats. An occasional meal that contains a reasonable quantity of unprocessed red meat (a 6- to 8-ounce steak, not a 22-ounce rib eye) is unlikely to cause harm.
The Claim: Your Friends Can Make You Fat
The Truth:
Researchers from Harvard Medical School addressed this question,
examining the spread of obesity in a large social network over a
thirty-two-year period. They found that obesity tended to occur in
clusters, and examination of these clusters of obese people confirmed
that obesity is socially contagious. A person’s risk of becoming obese
increased by nearly 60 percent if he or she had a friend who became
obese over the course of the study. Similarly, a sibling or spouse
becoming obese resulted in a 40 percent chance that other siblings or
the other spouse would also become obese. This obesity effect was
transmitted over long distances—friends separated by thousands of miles
had the same influence as those who lived next door.
The Claim: Sex Is Exercise
The Truth: It
depends on what you do and for how long. On average (and of course none
of us wants to lay claim to being average), sex lasts for five to
fifteen minutes and consumes about as much energy as walking one mile in
twenty minutes. The younger and more vigorous among us may double or
even triple this figure, reaching the threshold of vigorous exercise.
Alas, these people are the exception. So can we make an argument for
sex, heart-wise? The answer is probably yes. A healthy sex life
correlates with a healthy heart.
The Claim: Hormone Replacement Therapy Will Protect Your Heart
The Truth:
Hormone replacement therapy (HRT) should not be used to protect the
heart. But careful analysis reveals that HRT poses little to no risk
when used for short periods (six months) by women who are within ten
years of menopause. In these women, HRT is effective at relieving hot
flashes and night sweats. In contrast, in older women and those more
than ten years from menopause, HRT is riskier——it increases the
likelihood of heart attack and death from heart disease.
The Claim: Eggs Are Off-Limits
The Truth:
Everybody knows that eggs contain cholesterol, and it is widely believed
that eating foods rich in cholesterol leads to heart disease. Ergo, we
should not eat eggs, right? Not exactly. Today we understand that most
people can have one to three eggs per week. Eighty percent of your
body’s cholesterol is made by your liver, with diet contributing only
about 20 percent. Among dietary factors, saturated fats and trans fats
have a greater impact on blood cholesterol levels than does dietary
cholesterol. This is not a reason to fill your meals with cholesterol,
but it does mean that you can keep eggs in your diet.
The Claim: Video Games Can Make You Fit
The Truth: One
creative way to get your daily dose of exercise is to play games on the
Wii. One-third of the activities in the Wii sports video and fitness
packages require enough energy expenditure to qualify them as
moderate-intensity exercise. Golf and bowling involve only low-level
exertion, but you can work up a real sweat on the Wii with boxing and
tennis. The benefits of Wii and similar systems may extend even beyond
the heart. Recent studies show that games that require strategic
thinking boost both heart rate and cognitive abilities and memory. So,
no matter what your age, you can spice up your exercise routine by
including action video games in your program.
The Claim: To Get Fit Fast, Vary Your Exercise Pace
The Truth: Once
reserved for competitive athletes, interval training is a real option
for all of us. With this approach, you can squeeze your workouts into
shorter time periods, and possibly derive even greater benefits from
them. The principle of aerobic interval training is to vary the
intensity of your activity, alternating periods of strenuous exertion
with periods of recovery. For the runner, this may mean alternating
four-minute sprints with three-minute walks, using the walk to recover
from the heavier exertion. Nearly every aerobic activity can be
approached in this fashion. Compared to standard, steady exercise,
interval training produces greater increases in endurance, oxygen use
and general fitness. In addition, studies show that interval training
has beneficial effects on body weight and blood pressure.
The Claim: You Have to Be in the “Zone” to Get a Good Workout
The Truth: You
don’t have to use some arbitrary percentage of your maximum calculated
heart rate to guide your workouts. The truth is that you can have an
excellent workout at both relatively low and relatively high heart
rates, depending upon your exercise regimen and your own personal
cardiac characteristics. Tailor your workout to how you feel, and make
sure that you exert yourself—evidence of a good workout will be obvious
as the sweat begins to flow. The real key to exercising effectively is
to make sure that you are exercising consistently. As one researcher
noted, the most important calculation related to exercise is not your
maximum heart rate; it’s determining where in your busy schedule you can
fit a daily workout.
The Claim: You Can Die of a Broken Heart
The Truth: In
2005, Johns Hopkins researchers stunned the American public with their
description of a condition called stress cardiomyopathy, a potentially
life-threatening heart problem brought about by intense emotion. Hopkins
doctors studied nineteen people who suffered acute chest pain and
catastrophic heart failure after sudden emotional stress. The most
common precipitating event was death of a loved one, but in two cases
the life-threatening event was a surprise party. This understanding of
“broken heart syndrome” represents our best scientific evidence of a
biochemical link between emotional stress and heart disease.
Interestingly, almost all of the patients with stress cardiomyopathy
were women. We don’t yet understand why women may be more vulnerable
than men. But we do know that this story has a happy ending: all of the
patients recovered.
The Claim: Exercise is Dangerous for Heart Patients
The Truth:
Nearly all heart patients can benefit from exercise, and this holds true
for patients with heart failure and heart damage. The benefits of
aerobic exercise are actually not related to a direct effect on the
heart. Aerobic exercise works by increasing muscle efficiency, improving
the ability of the body’s muscles to extract oxygen from the blood.
Patients with congestive heart failure usually have reduced exercise
capacity, and this obviously makes it harder to exercise. Our advice is
to do whatever you must to find the motivation to exercise. The keys to
safety and success are to start aerobic exercise slowly and to increase
gradually. Walking is the ideal form of aerobic exercise for the heart
failure patient.
The Claim: Hot Tubs Can Hurt Your Heart
The Truth:
Staying in a hot tub or sauna for too long can certainly cause severe
dehydration and dangerous fluid and electrolyte problems. But a
ten-minute session in the hot tub or sauna will not hurt you or your
heart. Hot tubs and saunas do not cause heart attacks or heart problems
or interfere with cardiac pacemakers. As you enter the sauna or immerse
yourself in the hot tub, blood vessels near the skin dilate (enlarge),
causing a slight drop in blood pressure; this is rarely dangerous. You
can minimize the impact of this blood pressure change by getting in and
out slowly, which gives your body a moment to adjust to the temperature
change.
The Claim: A Stretch a Day Keeps the Heart Doc Away
The Truth: While
American studies of work-related stress and heart disease focus
primarily on the quality of the work environment, others have examined
the relationship between the quantity of work and heart health. In one
recent British study, researchers found that employees working three or
more overtime hours per day substantially increased their risk of
heart-related problems over a ten-year period. The risk was particularly
high among overtime workers with low decision-making capability and
high job strain. While the study did not tease out the cause of
increased heart disease among overtime workers, researchers noted that
employees who worked longer hours were more likely to smoke, had less
favorable cholesterol profiles, and had less time for leisure-time
exercise than their co-workers.
The Claim: You Can Be “Fat and Fit”
The Truth: A
small but vocal cadre of doctors believes that obesity and heart health
are not mutually exclusive. They use the term “metabolically healthy
obese” to refer to people who are obese but who do not have changes in
standard cardiac risk factors, suggesting that these people have nothing
to worry about. However, recent, careful studies in this group
demonstrate that they face an increased risk of developing heart disease
when compared to metabolically healthy people of normal weight. The
message here is clear: excess weight is a real and independent risk
factor for heart disease even when other standard risk factors are
absent. Don’t be lulled into a false sense of security if your weight is
high but your cholesterol is normal.
The Claim: You Can be Worked to Death
The Truth: While
American studies of work-related stress and heart disease focus
primarily on the quality of the work environment, others have examined
the relationship between the quantity of work and heart health. In one
recent British study, researchers found that employees working three or
more overtime hours per day substantially increased their risk of
heart-related problems over a ten-year period. The risk was particularly
high among overtime workers with low decision-making capability and
high job strain. While the study did not tease out the cause of
increased heart disease among overtime workers, researchers noted that
employees who worked longer hours were more likely to smoke, had less
favorable cholesterol profiles, and had less time for leisure-time
exercise than their co-workers.
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