A red meat nutrient sold as a supplement for weight loss and muscle growth may damage the heart and arteries, new research suggests.

Capsules of L-carnitine are widely available in health food stores and online.

They are advertised as a fat-burning slimming aid and powerful muscle builder - and are also said to help people with heart conditions.

But new research indicates a link between L-carnitine and heart disease. It may be a key reason why eating too much red meat can damage the heart, separate from the effects of saturated fat or cholesterol, say experts.

red meat

The studies show that L-carnitine is broken down by certain gut bacteria to produce a potentially harmful compound, trimethylamine N-oxide (TMAO).

Scientists found that high levels of L-carnitine in the blood were associated with heart disease, but only in individuals with raised TMAO.

Omnivorous individuals were found to produce more TMAO than vegetarians and vegans after consuming L-carnitine.
This suggests that, as well as containing L-carnitine, red meat favours the growth of gut bacteria that use the nutrient as an energy source, said the researchers.

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  • Processed Meat

    Hot dogs, bacon, sausage and deli meats -- even lean ones like turkey -- are made with <a href="http://www.health.harvard.edu/healthbeat/avoid-these-foods-for-a-healthier-heart">loads of sodium and preservatives</a>, often including nitrates and nitrites, both of which have been linked to heart problems. "With processing, you lose control over the quality of the ingredients," says <a href="http://drcynthia.com/dr-cynthia/">Cynthia Thaik, M.D.</a>, a Los Angeles-based cardiologist. Processed meats are also <a href="http://www.huffingtonpost.com/david-katz-md/nutrition-advice-the-trut_b_584758.html">higher in saturated fat and lower in protein</a> than any red meat you could prepare yourself, writes director of the Yale Prevention Research Center and HuffPost blogger, David Katz. Not convinced to stay away? Processed meats have also been linked to a <a href="http://www.huffingtonpost.com/2012/01/13/processed-meat-pancreatic-cancer-bacon-sausage_n_1204620.html">higher risk of diabetes <em>and</em> pancreatic cancer</a>.

  • Red Meat

    Yes, the processed picks are <em>worse</em> for your heart, but that doesn't mean you should go wild for steak. Instead, consider it more of a treat than a staple in your diet: It's still high in saturated fat, even when it's unprocessed. "I don't want to suggest that we have to go [completely] plant-based," says Thaik, "but moderation is always the key." If you're not planning on changing your carnivore ways anytime soon, at the very least pick a <a href="http://www.mayoclinic.com/health/cuts-of-beef/MY01387">lean cut of beef</a>, which, according to the USDA, contains less than 10 grams of total fat and 4.5 grams of saturated fat. Or opt for extra-lean, with 5 grams of total fat and less than 2 of saturated fat. Of the 29 cuts that meet these regulations, <a href="http://www.mayoclinic.com/health/cuts-of-beef/MY01387">five are extra-lean</a>, according to the Mayo Clinic, including eye of round roast or steak, sirloin tip side steak, top round roast and steak, bottom round roast and steak and top sirloin steak.

  • Pizza

    That cheesy slice may contain as much as <a href="http://www.realage.com/mens-health-guide/worst-junk-food-for-heart-disease-2">two thirds of your daily recommended limit of saturated fat</a>, according to Real Age, which is found mostly in animal products like beef, pork, butter, cream and milk. The American Heart Association recommends getting no more than <a href="http://www.heart.org/HEARTORG/Conditions/Cholesterol/PreventionTreatmentofHighCholesterol/Know-Your-Fats_UCM_305628_Article.jsp">7 percent of total daily calories from saturated fat</a>. (Based on a 2,000-calories-a-day diet, that totals out to about 15 grams a day of saturated fat). And even though you may think it's "just cheese," many dairy products are actually highly processed, says Thaik. To lighten up, skip extra cheese and top with veggies instead of pepperoni or sausage.

  • Trans Fats

    These fatty acids are created through processes that make vegetable oils more solid, according to the American Heart Association. They're cheap to produce, are used to make packaged and prepared foods last longer and can be re-used in frying. But <a href="http://www.heart.org/HEARTORG/GettingHealthy/FatsAndOils/Fats101/Trans-Fats_UCM_301120_Article.jsp">trans fats raise LDL or "bad" cholesterol while also lowering HDL or "good" cholesterol</a>, thereby putting your heart at risk. While a number of manufacturers have cut back on trans fat use in light of these health risks, packaged snacks, baked goods and some margarines may still contain it, according to EatingWell. Look for hydrogenated or partially hydrogenated oils on ingredients lists and beware the <a href="http://www.eatingwell.com/nutrition_health/heart_healthy_diet_center/the_worst_and_best_things_to_eat_for_your_heart?page=2">"zero trans fat" labels -- many are hiding .5 grams and rounding down to zero</a>. But considering that the AHA recommends getting <a href="http://www.heart.org/HEARTORG/GettingHealthy/FatsAndOils/Fats101/Trans-Fats_UCM_301120_Article.jsp">no more than 2 grams a day</a>, that adds up, and fast!

  • Fried Foods

    As restaurants use their frying oil over and over again, the <a href="http://www.livescience.com/14781-unhealthy-fried-foods-heart-attacks.html">fat becomes more and more saturated</a>, according to Live Science. And, as mentioned previously, trans fats are often lurking. Even though some restaurants may have cut back in the face of mounting health concerns, a number of joints still fry with solid oils like shortening, says Thaik. However, a 2012 found that <em>how</em> you fry makes a big difference. Among 41,000 Spanish adults, researchers found no link between fried food consumption and heart problems, likely because <a href="http://healthland.time.com/2012/01/25/a-healthier-way-to-eat-fried-foods/">cooking with heart-healthy olive oil is more common</a> than in the U.S, Time.com reported.

  • Soda

    "When we think of heart disease, a lot of people think cholesterol and fat, but we know that sugar, as it relates to obesity and the effect it has on insulin, has a lot to do with the development of artherosclerosis," says Thaik. In fact, drinking one sugary beverage a day leads to a <a href="http://vitals.nbcnews.com/_news/2012/03/12/10656108-soda-drinking-men-at-higher-risk-for-heart-attack">20 percent increase in a man's risk of having a heart attack</a>, according to a 2012 study, <a href="http://thechart.blogs.cnn.com/2012/03/12/a-soda-per-day-may-raise-heart-attack-risk/">even if those empty calories <em>aren't</em> causing weight gain</a>, CNN reported. Soda has previously been linked to <a href="http://www.ncbi.nlm.nih.gov/pubmed/19211821">increased rates of heart disease in women</a>, as well. And diet soda isn't any better. A 2012 study found that a daily diet soda <a href="http://www.nytimes.com/2012/02/28/health/research/diet-soft-drinks-linked-to-risk-of-heart-disease.html">increased risk for stroke, heart attack and death</a>, although the exact cause is not yet fully understood.

  • Fast Food

    There's little on the drive-thru menu that isn't loaded with saturated fat, trans fat, sugar or sodium, making most of your orders recipes for disaster. And the consequences for the heart are nearly immediate. A 2012 study examined the <a href="http://www.huffingtonpost.com/2012/11/27/fast-food-health-arteries-beauty_n_2198725.html">effects of fast food on the arteries after just one meal</a> and found that the ability of the blood vessels to dilate dropped by 24 percent, YouBeauty reported. "Not just fast food but processed food in general has a very high sodium content just by the pure nature of having to do the preservation," says Thaik. Soups and soy sauce are obvious culprits, she says, but saltwater sushi and even bread can be more surprising sources of salt.

A study of 2,595 patients undergoing heart check-ups showed "significant dose-dependent associations" between L-carnitine levels and the risk of coronary artery disease.

Links were also seen between L-carnitine and major events such as heart attacks, strokes and death.

In mice, L-carnitine supplements markedly increased TMAO levels and artery damage, but not if their gut bacteria was suppressed.

The scientists, led by Dr Stanley Hazen from the Cleveland Clinic in Ohio, US, wrote in the journal Nature Medicine: "Discovery of a link between L-carnitine ingestion, gut microbiota metabolism and CVD (cardiovascular disease) risk has broad health-related implications.

"Our studies reveal a new pathway potentially linking dietary red meat ingestion with atherosclerosis (narrowing of the arteries)."

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They added: "Our studies have public health relevance as L-carnitine is a common over-the-counter dietary supplement. Our results suggest that the safety of chronic L-carnitine supplementation should be examined, as high amounts of orally ingested L-carnitine may under some conditions foster growth of gut microbiota with an enhanced capacity to produce TMAO and potentially advance atherosclerosis."

Victoria Taylor, senior dietitian at the British Heart Foundation, said: "This is certainly an interesting discovery and sheds some light on why red meat might have an impact on heart health.

"While the findings won't necessarily mean a change to existing recommendations, these scientists have served up a good reminder for us to think about alternative sources of protein if we regularly eat a lot of red or processed meats.

"The odd meat-free day isn't such a bad thing and eating less meat automatically leaves room in your diet for other foods high in protein like fish, pulses, nuts and eggs, all of which should be part of a nutritious and varied diet.

"Unless told otherwise by a doctor or qualified health professional, we should be able to get all the nutrients we need from a healthy, balanced diet without additional supplements."

See also: Baldness Linked To Heart Disease In Men

Nutrition expert Professor Brian Ratcliffe, from Robert Gordon University in Scotland, said: "Dietary intakes of saturated fatty acids do not explain all the variation in blood cholesterol levels and these in turn do not explain all the variation in the occurrence of cardiovascular diseases (CVD).

"These diseases are complex and multi-factorial and this study provides another piece in the jigsaw puzzle showing the links between atherosclerosis and diet and lifestyle. The study is comprehensive and demonstrates a mechanism that may help to explain the observed associations between the consumption of red meat and the risk of CVD.

"This does not mean that we need to change current dietary recommendations because the advice is to limit the intake of red meat anyway. However, people who take supplements of L-carnitine for non-medical reasons may need to have some second thoughts."

Related on HuffPost:

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  • A: Ask About Your Family History

    It's not enough just to know whether anyone in your family had a heart attack or died of heart disease, says Dr. Goldberg. It's also important to ask about angina, bypass surgery, angioplasty, aortic abdominal aneurysm, stroke or peripheral artery disease, because having a family history of any of these conditions also increases your risk of developing a form of cardiovascular disease. Be sure to discuss a family legacy of any of these heart-related problems with your doctor. <strong>More from<a href="http://www.ivillage.com/" target="_hplink"> iVillage</a>:</strong> <a href="http://www.ivillage.com/celebrities-and-depression/4-b-230295?par=aol" target="_hplink">Celebs and Depression: Which Famous People Have Battled Mental Illness?</a> <a href="http://www.ivillage.com/fun-fitness-activities-children/4-b-374619?par=aol" target="_hplink">Get Your Kid Moving! Homework Dances, Camel Poses and More</a> <a href="http://www.ivillage.com/13-most-dangerous-teen-health-risks/4-b-352693?par=aol" target="_hplink">The 13 Most Dangerous Teen Health Risks</a>

  • B: Brush Up On Your Oral Hygiene

    It may seem like a stretch to think that your oral health could affect your heart but research has found a consistent link between periodontal disease (aka, gum disease) and cardiovascular disease, possibly through the role of inflammation. Researchers at SUNY at Buffalo found that women with periodontal disease had twice the risk of having a heart attack as those who didn't have gum disease. The solution: Brush your teeth thoroughly twice a day, floss at least once daily and see your dentist regularly for professional cleanings and checkups.

  • C: Cultivate Social Connections

    If the prospect of a lively social life doesn't get you jazzed, this reality might: Having strong social support in your life can lower your resting blood pressure and other cardiovascular functions in a positive way, according to a study from the National University of Ireland. On the flip side, research at the University of Pittsburgh School of Medicine found that high levels of loneliness increase a woman's risk of heart disease by 76 percent. Try to make new friends by taking classes, joining clubs or volunteering, and keep your old pals by regularly staying in touch with people you love and trust -- for the sake of your mood and heart.

  • D: De-Stress Regularly

    When you're juggling work and home responsibilities, and dealing with stress overload from multiple directions, it's crucial to find stress management techniques that work for you. "We're finding that untamed stress has a direct impact on heart health," says Tracy Stevens, M.D., a cardiologist at Saint Luke's Mid America Heart Institute in Kansas City, Mo., and a spokesperson for the American Heart Association (AHA). "It's the constant bombardment of adrenaline that raises blood pressure and destabilizes plaque in your arteries." Find your personal decompression valve -- yoga or meditation, for example -- and use it regularly to relieve the effects of stress on your body and mind. It also helps to take mini-breaks for deep breathing or a good laugh during the day to short-circuit some of the effects of stress and recharge your mental batteries.

  • E: Eat Smarter

    As far as your heart is concerned, it's best to consume a balanced diet that follows a few key principles. First, it should replace saturated fats, trans fats and cholesterol with healthy monounsaturated and polyunsaturated fats. It should also contain plenty of omega-3 fatty acids, as well as fruits, vegetables, beans, legumes and whole grains, Dr. Goldberg says. And it should include nuts, fat-free or low-fat milk and dairy products, as well as skinless poultry and lean meats. When designing your plate, keep it simple and colorful by including one serving of protein and two different colored vegetables and/or fruits in each meal, Dr. Stevens advises.

  • F: Forget About Vitamin Supplements

    Despite all the hope and hype over their potential heart-protective powers, "antioxidant vitamins [such as A, C or E] and B-complex vitamins have not been shown to be beneficial in preventing heart disease," says Robert O. Bonow, M.D., the Goldberg distinguished professor of cardiology at Northwestern Memorial Hospital in Chicago, director of the Center for Cardiovascular Innovation and past president of the AHA. "Mother Nature does a good job of packing vitamins into healthy foods like leafy greens, fresh fruits and vegetables and whole grains," he says. You're better off eating healthy, whole foods than swallowing a supplement. Consider "stocking up on supplements" as one less thing to put on your heart-smart to-do list.

  • G: Get Moving

    A sedentary lifestyle is a risk factor for heart disease, so try to incorporate more movement into everyday life by taking the stairs instead of the elevator, walking for your errands instead of driving, and so on. "Any physical activity is better than no physical activity," Dr. Bonow says, "so whatever you're doing, you should start doing more than you're doing now." The AHA also recommends at least 30 minutes of moderate-intensity aerobic exercise five days per week and strength training twice a week. The latest thinking is that resistance training can help improve your body composition so that you have less body fat and more lean muscle mass, a change that can favorably affect your cholesterol levels.

  • H: Heed Your Hormonal Issues

    Taking birth control pills is considered safe for healthy women who don't smoke. But hormone replacement therapy is another story: In recent years, hormone therapy (HT) has fallen out of favor because clinical trials concluded it was ineffective at protecting against heart disease and may actually increase the risk of blood clots, stroke and breast cancer. That's why the current thinking is that HT should only be used at the lowest possible dose for the shortest amount of time possible to treat menopausal symptoms. If hot flashes and other menopausal symptoms are driving you nuts, talk to your doctor about the pros and cons of HT in your case.

  • I: inquire Sbout Specialized Screening Tests

    Ask your doctor if there are any unusual screening tests you should have. If, for example, you have a strong family history of heart disease, but your cholesterol, blood pressure, blood sugar and weight are within normal ranges, your doctor may choose to probe a bit deeper in the testing arena. "Looking at C-reactive protein (CRP) levels [a marker of inflammation], Lp(a) [a harmful type of small-particle cholesterol] and apolipoproteins [proteins that are associated with different types of cholesterol] may tell us if something else is going on that we need to know about," Dr. Bonow explains. Finding out that one of these measures is out of whack may prompt your doctor to prescribe a cholesterol-lowering statin drug sooner rather than later.

  • J: Jump On The Omega Bandwagon

    Omega-3 fatty acids (present in fatty fish like salmon, sardines, lake trout, herring, mackerel and tuna, as well as walnuts, canola oil and flaxseed) have powerful anti-inflammatory effects that are good for your heart. They've been shown to decrease the risk of heart arrhythmias, reduce triglyceride levels and blood pressure, and decrease the buildup of atherosclerotic plaque, Dr. Bonow says. That's why the AHA recommends that everyone consume fatty fish at least twice a week. If you have heart disease or need to lower your triglycerides, talk to your doctor about whether you should consume omega-3 fatty acid supplements (in the form of EPA plus DHA).

  • K: Know Your Numbers

    Find out what your levels of blood pressure, cholesterol (including total cholesterol, LDL, HDL and triglycerides) and fasting blood sugar and/or hemoglobin A1C levels are -- and whether they're high, low or in the optimal range. These are among the leading risk factors for heart disease -- and you can modify them through diet, exercise and other lifestyle changes or by taking medication. "These risk factors are not going to go away by looking at numbers on a lab report," Dr. Goldberg warns. "You need to decide with your doctor what you're going to focus on first." Then try to knock them down through lifestyle changes and/or medications.

  • L: Lose Excess Weight

    It probably seems like an obvious risk factor, but experts say many people are too complacent about carrying extra pounds because they don't realize that being overweight -- not just obese -- can raise their risk of heart disease. "People need to be more aggressive about dealing with excess weight because it's not just a risk for cardiovascular disease but also for high blood pressure and diabetes, which also increase the risk for heart disease," says Dr. Goldberg. Consider these three compelling reasons to upgrade your diet, downsize your portions, move more and take other steps to slim down.

  • M: Map Out A Heart-Healthy Plan

    Schedule an appointment with your doctor to discuss the heart-related risk factors that are most relevant to you, given your health status, age and family history and then come up with a strategy for how to best improve or manage them, Dr. Goldberg suggests. Some questions to get the conversation started: How significant is my personal risk for heart disease? How much and what kind of exercise should I be doing, given my overall health? What else should I be doing to prevent heart disease? Your doctor may recommend that you take certain medications or consult a sleep specialist about a sleep disorder (such as sleep apnea) that could be interfering with your ability to get good quality zzz's.

  • N: Nix Unhealthy Fats

    Not all fats are created equal. As far as your heart is concerned, there are good fats and bad fats. That's why it's wise to replace saturated fats (from red meat and full-fat dairy products) and trans fats (in margarine, other spreads and some crackers and cookies) with healthy monounsaturated fats (in olive and canola oils, avocados, nuts and seeds) and polyunsaturated fats (in corn oil and fatty fish). The latest AHA guidelines recommend limiting your saturated fat intake to less than 7 percent of your total calories and your trans fat intake to less than 1 percent. Your total fat intake, including good fats, should max out around 30 percent of your total calories, says Dr. Goldberg.

  • O: Opt For Healthier Cooking Techniques

    To slim down and improve your heart health, you may want to change how you prepare foods. First, trim the fat off meats and the skin off poultry before you cook them. Then, opt for baking, broiling, roasting or poaching instead of frying or sauteing foods. It's also wise to cut back on salt and to use herbs instead, and to switch from cooking with butter or margarine to using a plant sterol-based spread (like Benecol, Earth Balance or Smart Balance), Dr. Goldberg says. When you do need to fry or saute ingredients, use a nonstick pan and a nonstick cooking spray.

  • P: Pay Attention To The "Multiplier Effect"

    If having one risk factor for heart disease is bad, having two or more is far worse. That's because risk factors tend to "gang up and worsen each other's effects," according to the National Heart, Lung and Blood Institute (NHLBI). While it's far from ideal to have high blood pressure, having hypertension, diabetes and cholesterol abnormalities is far more serious and puts an added strain on your cardiovascular system. In fact, "having two risk factors increases the chance of developing heart disease fourfold," according to the NHLBI, while "having three or more risk factors increases the chance more than tenfold." The bottom line: Take every risk factor for heart disease seriously and take action to get it under good control.

  • Q: Quit Smoking

    Women have a lower risk of heart disease before menopause because estrogen protects our hearts to some extent. But that's not true for female smokers. Smoking erases the natural protection of estrogen, putting premenopausal women at just as high a risk for heart disease as men, notes Dr. Bonow. Even exposure to secondhand smoke is risky. A study from New Zealand suggests that women who are exposed to secondhand smoke at home have up to a 35 percent increased risk of developing cardiovascular disease as they get older. The best way to quit is highly individual, but you may want to use more than one technique, such as taking a medication that's used for smoking cessation, using hypnosis or acupuncture, joining a smoking cessation program or using nicotine replacement therapy. If you smoke, talk to your doctor about what's likely to help you kick the habit.

  • R: Reduce Your Portions

    "You can't eat the same way when you're 40 as you did when you were 20, because women's metabolisms change," Dr. Goldberg says. Trimming your portion sizes is one of the easiest ways to eat less and lose weight. Switch from a dinner plate to a salad plate, or from a giant soup bowl to a cup. Then, fill up on low-calorie foods that take up a lot of space in the stomach (like mixed-greens salads or broth-based, low-sodium vegetable soups), and it'll be even easier to consume fewer calories in every meal. Consider having half a bowl of cereal topped with lots of berries for breakfast, half a sandwich (instead of a whole one) and a cup of soup for lunch, and starting dinner with a large mixed-greens salad (lightly dressed) before digging into a smaller main course.

  • S: Sleep Well And Enough

    Regularly sleeping five or fewer hours per night can increase a woman's risk of heart disease by 45 percent, according to research at Vancouver General Hospital in British Columbia. This may be because insufficient sleep causes increased levels of the stress hormone cortisol, which can damage blood vessels, raise blood pressure and increase the accumulation of belly fat. Meanwhile, a study at the University of Pittsburgh School of Medicine found that the chances of developing metabolic syndrome -- a collection of heart disease risk factors, including abdominal obesity, high triglycerides, low HDL cholesterol, high blood pressure and elevated fasting blood sugar -- increased by more than 45 percent among adults ages 30 to 54 who usually sleep less than seven hours per night. So ditch the late-night chores and make sleep a priority. If you consistently have trouble falling or staying asleep, see your doctor.

  • T: Tell Your Doctor About Your Reproductive Life

    Besides alerting your doctor to conditions that may directly increase your risk of heart disease, it's wise to inform her about reproductive-related risk factors. Say you had preeclampsia, a disorder characterized by high blood pressure and protein in the urine, while you were pregnant. You then also have a twofold increased risk of developing heart disease in your 50s, Dr. Goldberg says. If you had gestational diabetes during pregnancy, you have a 50 percent chance of developing Type 2 diabetes within 10 years, which also would crank up your heart disease risk. It's important for your doctor to know about these conditions so she can monitor you closely and request the right tests at the right times. Also, make sure your doctor knows about underlying medical conditions -- like rheumatoid arthritis, lupus and polycystic ovarian syndrome -- that may affect your heart.

  • U: Update Your Status

    No, we're not talking about Facebook. We're talking about telling your doctor about any relatives who develop heart-related problems or risk factors for heart disease. Similarly, keep all your doctors in the loop about new risk factors you develop, such as cholesterol abnormalities, elevated blood sugar or increased blood pressure (even if the latter two fall in the category of prediabetes or prehypertension, rather than the full-blown condition). After all, your cholesterol, blood pressure and blood sugar levels can change every decade, especially after 40, even if you aren't doing anything differently, Dr. Goldberg notes, and these changes can affect your risk of heart disease. By taking your latest risk factors, family history and lifestyle into account, your doc can provide a sense of your current risk of developing heart-related problems

  • V: Vow To Honor Your Limits

    It's true that moderate amounts of alcohol (as in one drink per day for women) can have a beneficial effect on your heart. But overdoing it can weaken the heart muscle, raise triglycerides, increase blood pressure and lead to weight gain (courtesy of those empty calories), Dr. Stevens warns. So go easy on the cocktails. Meanwhile, salt can increase blood pressure, so limit your intake to around 1,500 milligrams per day. Ditch the saltshaker and get in the habit of checking the sodium content of packaged foods before you buy them. It's also smart to curb your intake of refined carbohydrates (think: white flour) and simple sugars. "The more processed food you consume, the more it plays havoc with your insulin levels, which can ultimately increase your risk of developing Type 2 diabetes and heart disease," Dr. Stevens says.

  • W: Whittle Your Middle

    Excess belly fat (a waist circumference over 35 inches for women) is a hallmark of the metabolic syndrome, a cluster of risk factors that increases your risk of heart disease. This is true even if your weight seems normal and your body mass index is under 25. Does this describe you? Then it's time to whittle your middle -- by reducing your stress level and getting plenty of shut-eye (seven to nine hours per night) to keep your hormone levels balanced and reduce your susceptibility to belly fat, says Molly Kimball, R.D., a sports nutritionist at Ochsner's Elmwood Fitness Center in New Orleans. Also, do interval training -- bursts of more intense exercise in your workout -- to rev up your heart rate and burn more calories to help you drop body fat. Curb your carb intake, too, Kimball advises, and "stick with veggies and whole grains. If you must have carbs, make them whole grain rather than processed ones."

  • X: X-amine Your Emotional Pulse

    "Depression is increasingly being recognized as an important predictor of heart disease -- it's right up there with high cholesterol, smoking and high blood pressure," says Richard A. Stein, M.D., professor of medicine and cardiology at the New York University School of Medicine in New York City and author of "Outliving Heart Disease." This may be partly because people who are depressed are less likely to exercise regularly, eat healthfully and take their medications as directed. But there also seems to be a direct link: Depression may alter heart rhythms and increase blood pressure, platelet reactivity and inflammation -- all risk factors for heart disease -- in part because it is associated with elevated levels of cortisol, a stress hormone, Dr. Stein says. Chronic anxiety, loneliness, anger and out-of-control stress can have similar effects. If you have any of these mood issues on a regular basis, talk to your doctor about the best treatment options for you, such as counseling or medication.

  • Y: Yield To Worrisome Symptoms

    The most common heart attack symptom in women is chest pain or discomfort, just as it is for men. But women are more likely to experience atypical symptoms of a heart attack such as shortness of breath; nausea and vomiting; neck, back or jaw pain; lightheadedness; or breaking out in a cold sweat -- symptoms that aren't always recognized as heart related, Dr. Bonow says. Get any of these symptoms checked out immediately -- by calling 911 -- even if you're not sure it's a heart attack. If it is, every minute counts toward increasing your chances of recovery.

  • Z: Zap Unnecessary Stress

    Besides taking a toll on your overall health, being in a frequent state of stress overload can affect your behavior in ways that aren't good for your heart. Simply put, "People who are highly stressed aren't likely to do healthy things like eat well or avoid smoking," Dr. Stevens says. Try to set healthy limits in your life by delegating responsibilities when possible, saying np to nonessential requests and making an effort to lead a balanced life. Doing so will help you carve out precious time to take better care of your own body and mind. Ultimately, it really could be a matter of life or death. <strong>More from<a href="http://www.ivillage.com/" target="_hplink"> iVillage</a>:</strong> <a href="http://www.ivillage.com/celebrities-and-depression/4-b-230295?par=aol" target="_hplink">Celebs and Depression: Which Famous People Have Battled Mental Illness?</a> <a href="http://www.ivillage.com/fun-fitness-activities-children/4-b-374619?par=aol" target="_hplink">Get Your Kid Moving! Homework Dances, Camel Poses and More</a> <a href="http://www.ivillage.com/13-most-dangerous-teen-health-risks/4-b-352693?par=aol" target="_hplink">The 13 Most Dangerous Teen Health Risks</a>