Fact or fabrication? When it comes to health, there's a lot of "information" floating around on the grapevine, and not all of it is recognizable for what it is - which may be anything from truth to half-truth to nothing-like-the-truth. Which of these medical "facts" do you believe?

1. If you're pregnant and carrying a male fetus, it will "show high."
Here's another one: suspend a pregnant woman's wedding ring on a thread over her belly. If the ring swings in a circle, it's a girl; if it swings in a straight line, it's a boy. Or there's the belief that if you're having a lot of morning sickness during the first trimester, you're carrying a girl. These are all fun ways to guess the sex of the unborn baby but they're nothing more than games. How you carry your baby has nothing to do with gender. In fact, you may find that even in a family that is all girls or all boys, the babies all carried differently before they were born.

2. You're guaranteed to lose weight on a low-fat diet.
Although you're wise to cut your fat intake, low-fat is not necessarily low-calorie. Once upon a time, a low-fat diet was one that consisted of a lot of fruits, vegetables and fibre-rich foods. It was easy to lose weight then because these foods not only are low-calorie but also fill you up. However, things have changed and supermarket shelves are now flooded with low-fat products, such as cookies and muffins, that are often high in calories from sugar. Low-fat processed foods don't contain the nutrients and fibre found in low-fat whole foods. As a result, you may feel hungry soon after eating them. To lose weight, you need to cut calories and increase your physical activity as well as cut your fat intake.

3. Sitting too close to the TV will ruin your vision.
Being close to the TV won't ruin your eyesight, but sitting less than 1.5 metres from the set can tire the muscles that focus the lens of the eye, resulting in eyestrain and tired eyes that burn and water. Make sure you sit far enough from the TV set, have enough light in the room and give your eyes a break by refocusing your gaze during commercial breaks.

4. Herbs are harmless because they're natural.
While many herbs have been around for centuries, it's only recently that some of the problems associated with their use have come to light; for instance, kava — popular for its ability to reduce anxiety — has now been shown to be toxic to the liver. Ginkgo leaf extracts, promoted to improve mental clarity and treat dementia and peripheral vascular disease, are known to cause headaches, nausea and diarrhea. Echinacea, St. John's wort, German chamomile and ginkgo biloba have been reported to cause allergic reactions. It's a good idea to tell your family physician about any "natural" products or supplements you're taking — or considering taking — to find out whether they're compatible with your health needs and other medications you may already be taking.

5. Everyone should take acetylsalicylic acid (ASA) every day to prevent a heart attack or stroke.
Yes, if you've already had a heart attack or stroke. Studies show that taking ASA daily can reduce the risk of having another heart attack by 25 per cent. As a result, ASA has become a standard treatment for many types of heart disease and stroke and is an important part of emergency treatment for a heart attack that's in progress. However, researchers have yet to determine whether ASA can prevent a first heart attack or stroke, and for people who are perfectly healthy, the risk of gastrointestinal upset — even bleeding — can be significant. Bottom line? Always check with your physician before embarking on any drug therapy, including taking ASA each day to prevent a heart attack or stroke.

6. The main reason to brush your teeth is to remove food debris.
Brushing is a great way to get the gunk out of your teeth after a meal. But the real benefit of brushing is to eliminate the bacteria that cause cavities and gum disease. Bacterial plaque constantly forms on teeth and gums and is one of the main causes of tooth decay and gum disease. Since plaque-building bacteria thrive on foods that contain sugars and starches, you need to brush your teeth twice a day for at least two minutes each time and floss once a day. If calcified plaque, known as tartar, starts to get under your gum line, it's time to head to the dentist for a professional cleaning, usually every six to nine months.

7. Once you've had a caesarean section, you'll always have to have one.
Not so. Fifty to 80 per cent of women who deliver by C-section because their labour failed to progress (known as dystocia) or their babies were in a breech position can successfully have vaginal deliveries for the next baby. This is known as vaginal birth after caesarean. There are, however, some circumstances under which a woman would always have to have another C-section; these include a vertical incision for the original C-section or extensive uterine surgery. Both can increase the risk of uterine rupture during a subsequent labour and delivery.

8. A heart attack is always accompanied by significant pain.
While men having heart attacks typically feel a crushing, squeezing pain in their chests, often accompanied by sweating, shortness of breath and light-headedness, women experiencing heart attacks are more likely to complain of vague chest discomfort and nausea. Since these symptoms can come and go, many women chalk them up to heartburn. When they do have significant chest pain, women are more likely than men to describe it as radiating from their chests up their necks, jaws or backs, whereas men describe it as just pain in their chests. Whatever the symptoms, if you're concerned that you may be having a heart attack, call 911 for an ambulance to the nearest emergency department and chew on ASA en route. Medical therapy for a heart attack is most beneficial during the first two hours, when risk of death is highest.

9. Starve a fever; feed a cold.
At some point in history, people may have believed that stuffing your face while you had a cold would get rid of it, but modern doctors say that's a lot of hooey. Colds are caused by viruses, and the only way to feel better is to rest and drink lots of fluids. These fluids replenish those used by the immune system to fight off the virus. If you have a fever that's higher than 38 C for more than 48 hours, then it's not about whether to eat; it's about consulting a doctor to find out what's causing the fever. If you feel that having something soothing, such as chicken soup, will comfort you, then go ahead. Hey, if it makes you feel better, why not? But it's not going to cure you.

10. Ulcers are caused by stress.
Doctors used to think that a peptic ulcer — a sore on the lining of the stomach or the top part of the small intestine (known as the duodenum) — was the result of too much stress or spicy food or both. However, research has pinned the blame on Helicobacter pylori (H. pylori), a spiral-shaped bacterium that causes more than 90 per cent of ulcers by weakening the protective mucus coating of the stomach and duodenum, allowing acid to get through to the sensitive lining underneath. While it's not clear how people get infected with H. pylori, researchers suspect that it's from person-to-person contact, either through infected saliva, vomit or fecal matter that comes into contact with hands, food or water. Some people who have used nonsteroidal anti-inflammatory drugs, such as ibuprofen or ASA, for a long time are also prone to developing ulcers. In a few cases, ulcers are caused by cancerous tumours in the stomach or pancreas.

11. Breast cancer has reached epidemic proportions in young women.
Actually, this isn't true. While breast cancer is the most frequently diagnosed cancer among Canadian women, with the exception of nonmelanoma skin cancer, few of these cases involve young women. With an average of 407 Canadian women diagnosed with breast cancer each week — and approximately 102 dying each week as a result — it's no wonder that women of all ages, particularly young women, are concerned. The reality is, however, that breast cancer is much more common in older women. Only 22 per cent of cases occur in women under 50 and only five per cent in women under 40.

12. Vegetarians don't get adequate protein in their diets.
You don't necessarily have to eat meat to get adequate amounts of dietary protein. But to get enough protein, vegetarians do need to eat a wide variety of foods, including legumes, dried peas, beans, chickpeas, kidney beans, whole grains, nuts, seeds and soy products. Whether you're a lacto-ovo vegetarian (who eats dairy products and eggs), lacto vegetarian (who eats dairy products) or vegan (who eats no animal products), you may wish to consult a registered dietitian or nutritionist for an eating plan that ensures you're also getting enough calcium, iron, vitamins B12 and D, and zinc.

13. It's impossible to drink too many fluids while exercising.
You may think it's safe to drink as much water as you want when you're sweating, but studies of athletes show that drinking more than 500 millilitres of water per hour can lead to hyponatremia, or water intoxication. This condition — though rare — can occur when blood becomes so diluted that it doesn't contain enough salt for adequate brain, heart and muscle function. In a worst-case scenario, water intoxication can result in coma and even death. Some people with water intoxication have no symptoms; others have symptoms similar to those of dehydration (apathy, confusion, nausea, fatigue). However, water intoxication is usually associated with long-distance running and cycling. It's important to drink a lot when you're exercising in the heat, but instead of drinking a lot of water all at once, drink smaller amounts — say 125 to 175 millilitres at a time. And while sports drinks that contain sugar and calories are OK if you're exercising for four hours or more (such as in a marathon or cycling event) or working out in a hot environment, water is generally the best choice. Whether it's bottled or comes from a tap is up to you.

14. Cracking your knuckles will cause arthritis or big knuckles.
Cracking your knuckles occasionally may annoy those around you and make your joints sore, but there's no evidence that this directly causes arthritis, a disorder characterized by sore and swollen joints. If you crack your knuckles all the time, however, you could injure the cartilage and cause the joints to swell. Keep this up and eventually it may lead to degenerative joint disease, such as arthritis.

15. Fresh fruits and vegetables are always more nutritious than frozen or canned.
It depends. If fresh fruits and vegetables have been languishing in the fridge for a week, some of the vitamins may have been lost — just as they can leach out into cooking water. In that case, fresh produce may not have the same nutritional value as canned or frozen fruits and vegetables. Similarly, if you leave cut-up fruits or vegetables on a kitchen counter for more than 20 minutes, exposure to air may rob them of some of their vitamins. Generally speaking, however, frozen or canned fruits and vegetables are just as vitamin-rich as fresh.

16. Children with asthma shouldn't play sports.
Parents and doctors used to counsel children with asthma to stay away from all sports. Physical activity, the thinking went, increases breathing rate and could trigger asthma, a disease of the respiratory system characterized by coughing, wheezing, tightness in the chest and shortness of breath. We now know that exercise, particularly aerobic exercise, can actually improve the lung power of a person with asthma. Studies show that when people with asthma exercise, they have fewer attacks, use less medication and miss less time at school. For this reason, children whose asthma is well controlled by medication and avoidance of triggers should be encouraged to take part in most sports and other physical activities — even if they have exercise-induced asthma (EIA). While activities that are more intense and sustained, such as long periods of running, should be avoided, there are many sports that are less likely to trigger EIA; they include walking, cycling, swimming and sports that require short bursts of energy, such as baseball, softball, volleyball, tennis, football, wrestling, golf, gymnastics and short-distance track-and-field events.

17. Becoming a vegetarian will ensure that you'll lose weight and be healthier.
While a vegetarian diet can be nutritious, your food choices — not whether you choose to eat meat — will determine whether you'll lose weight. If you order the dressing-soaked Caesar salad and french fries rather than grilled chicken breast and a lightly dressed green salad at a fast-food restaurant, you could be eating a meal that's actually higher in fat and calories than a meat-based one. Also, if you don't know how to eat to stave off hunger on a vegetarian diet, you may end up actually eating more. It's all about balance.

18. Women are more likely to die from cancer — especially breast cancer — than from any other cause.
Wrong. Heart disease kills more women (and men) than all cancers combined. In 1999, the latest year for which statistics are available, cardiovascular disease accounted for 39,134 deaths of Canadian women and 37 per cent of all female deaths compared with 28,624 deaths for women from all cancers, 17 per cent of which were from breast cancer. Of the cancers, lung cancer kills more women than breast cancer, even though more women are actually diagnosed with breast cancer. In 2002, for instance, 20,500 Canadian women were newly diagnosed with breast cancer; of this group, 25 per cent died. By comparison, only 8,800 women were diagnosed with lung cancer in 2002, but the disease killed 87 per cent.

19. Gum that is swallowed takes seven years to digest.
If swallowed, the average piece of gum will be expelled in the stool — just like any other food — a few days later. Gum, which is not digested, takes slightly longer to be expelled than food that is digested and passes through the intestinal tract in about 24 hours. Only if a very small child swallows a huge wad of gum is there any danger of the gum causing an intestinal obstruction. In that case, it could take much longer to be expelled but nothing close to seven years. In severe cases, this could lead to distension of the intestines and severe abdominal cramps; it would require surgery to remove the obstruction.

20. Hyper people are more likely to have hypertension.
Even though a person who's in a rage can temporarily increase his blood pressure (witness the beet-red face), the reality is that a person's temperament doesn't cause high blood pressure, a risk factor for heart disease and stroke. In about 10 per cent of people with high blood pressure (greater than or equal to 140 mmhg systolic or greater than or equal to 90 mmhg diastolic pressure), the problem is caused by kidney disease, hormonal disorders or certain drugs. But in most cases of hypertension, the cause is unknown.

21. You can't get breast cancer if nobody in your family has it.
Unfortunately, this is not the case. It's true that women with a family history of breast cancer are more likely to develop it than women with no family history; for example, if your mother or sister had breast cancer prior to menopause, your risk increases by six times and by 10 times if your mother or sister had cancer in both breasts. Similarly, if your mother or sister carries the BRCA1 or BRCA2 gene — considered to be genetic markers for breast cancer — your risk of breast cancer is markedly increased. However, many cases of breast cancer occur in women with no family history of the disease; in fact, 70 per cent of women diagnosed with breast cancer have no known risk factors. Other factors that appear to increase your risk of developing breast cancer include:
&#8226 being 50 years of age or older;
&#8226 a family history of cervical, uterine, colorectal or ovarian cancers;
&#8226 previous breast disorders, such as benign breast cysts;
&#8226 having a first pregnancy after 30 or never being pregnant;
&#8226 early menstruation and a later-than-average menopause (a longer exposure to estrogen increases the risk); and
&#8226 living in a developed country (experts suspect this is due to high-fat diets and perhaps environmental pollution).

Research continues on the effects of diet, obesity, alcohol, hormone replacement therapy, smoking and level of physical activity on your risk of developing breast cancer.

22. Beef will raise your blood cholesterol level higher than poultry or seafood.
Not necessarily. It isn't just how much cholesterol a particular food contains but also the kind of fat the food contains and how this fat affects blood cholesterol levels when eaten. For instance, saturated fat has more of an impact on boosting blood cholesterol levels than the actual cholesterol content of foods, so if the beef is lean and well trimmed, it could contain less cholesterol-boosting saturated fat than a chicken drumstick (dark meat)
with the skin on it. And some seafood, such as shrimp, may be high in cholesterol but may also contain heart-healthy polyunsaturated fat, which can help lower blood fats.

23. All fibre helps prevent heart disease.
There are two types of dietary fibre, and one of them is thought to promote heart health: it's called soluble dietary fibre and it can be found in oat products, such as oat bran and oatmeal; legumes, such as dried beans, peas and lentils; and pectin-rich fruits, such as apples, strawberries and citrus fruits. Soluble fibre seems to help stabilize blood sugar levels and lower blood cholesterol, especially when it is high. On the other hand, insoluble fibre, found in wheat bran and wheat bran cereals, whole grain foods, fruits and vegetables, hasn't been directly linked to boosting heart health by itself; however, it may help prevent certain cancers, including colon cancer.

24. All vegetable oils are heart healthy.
Some are, some aren't. Coconut, palm and palm kernel oils — often used in cookies, crackers and cakes — are sources of saturated fats, which can raise blood cholesterol levels and be detrimental to heart health. When vegetable oils are hydrogenated or partially hydrogenated (the kinds found in hard margarines, cookies, crackers and commercially baked products), they can raise blood cholesterol levels. Read the nutrition information on the label and look for "partially hydrogenated" to indicate the presence of unhealthy trans-fatty acids. Instead, choose extra-virgin olive, canola and peanut oils, which contain monounsaturated fats that can also help lower blood cholesterol. Similarly, safflower, sunflower and corn oils contain polyunsaturated fats, which can help lower blood cholesterol.

25. Eating after 8 p.m. causes weight gain.
It's probably wise to space your calories out throughout the day to coincide with your activity levels, but there's no magical moment weightwise that happens at eight o'clock at night. However, during the evening, you may be more apt to wind down in front of the TV, and if you sit eating high-calorie snacks like chips, you may pack on the pounds. Eating these snacks at night may be a sign that you haven't eaten enough during the day. If you eat several small and nutritionally balanced meals every three to four hours throughout the day, you won't get the munchies later on.

Experts consulted include Dr. Harold Dion, president of the Quebec College of Family Physicians; Dr. Anthony Graham, spokesperson for the Heart and Stroke Foundation and director of ambulatory care at St. Michael's Hospital in Toronto; Dr. Robert Reid, a professor in the department of obstetrics and gynecology at Queens University in Kingston, Ont.; Rosie Schwartz, a nutritionist and registered dietitian; Dr. Joey Shulman, a nutritionist; and Dr. Barbara Whylie, executive director of the Canadian Cancer Society.