Health Q and A | The Canadian Encyclopedia


Health Q and A

It's quite simple. Exercise, diet and weight-control remain the pillars of good health. But as our knowledge grows, so do our options for optimizing our health.

This article was originally published in Maclean's Magazine on April 30, 2007

Health Q and A

It's quite simple. Exercise, diet and weight-control remain the pillars of good health. But as our knowledge grows, so do our options for optimizing our health. For instance, all fruit is good for you, correct? Well, yes, but there is also such a thing as "good" and "bad" fruit, and the types you eat can have an impact on your body's production of insulin, which in turn affects weight gain. We have now also identified a "coffee gene," which determines how quickly a person processes caffeine. The gene, some researchers argue, is linked to heart attacks in people who drink caffeinated drinks to excess. We know the sun causes cancer, but it's also essential for vitamin D production.

Confusion is understandable. This is why Maclean's, in collaboration with Dr. Elaine Chin and Scienta Health, has complied a list of questions and answers, coupled with background on currently available tests. It may whet your appetite for becoming proactive in ensuring your long-term, symptom-free good health. Bon appétit.

How many "good" low-glycemic fruits do you consume per day?

Not all fruits are created equal. Apples, oranges and plums, for instance, have a lower glycemic index than fruit like bananas, pineapples and watermelon. Those "good" fruits don't push blood-sugar levels quite so high, and reduce the body's need to release insulin. Keeping insulin in check is good because the hormone facilitates the conversion of carbohydrates into fat for storage, which leads to weight gain. Fruit is also an excellent source of antioxidants, which neutralize free radicals that can damage cells. A hormone test for insulin can be helpful in gauging health, while a urine analysis can detect free radicals.

How much caffeine do you drink?

Most of us can't go without our morning cup of joe. But there may be a price to be paid for that jolt of caffeine - and it appears to depend on your genes. A growing body of research suggests some people carry a version of the so-called "coffee gene," which causes them to digest caffeine more slowly than individuals with the fast-acting genetic version. The theory suggests carriers of the slow gene who consume large quantities of caffeine run a higher risk of having a heart attack. Currently, researchers are racing to develop a genetic test to screen for the slow gene. But until one exists, health advocates say it's best to err on the safe side and keep consumption of coffee, tea, or caffeinated pop down to one, or at most two eight-ounce servings per day. And that's only if there are no health issues like poor sleep, weight gain, bone loss (caffeine prevents calcium absorption) or breast cysts. Another knock against caffeine is it stimulates cortisol secretion by the adrenal glands. Known as the stress hormone, cortisol can disrupt sleep and stimulates secretion of insulin, which is associated with weight gain and difficulty losing weight. A test to monitor cortisol is available.

What portion of protein intake should be red meat?

Ideally, red meat would represent about 30 per cent of your recommended daily animal protein intake (with fish and poultry accounting for another 30 per cent each, with the balance derived from non-meat sources like beans and lentils). That assumes no health conditions associated with cholesterol or iron accumulation. By now just about everyone knows red meat is a major source of dietary cholesterol, and doctors counsel patients with high cholesterol to reduce their intake. Other concerns include red meats as a source of iron, a free radical that increases oxidation and cell damage, and arachidonic acid, a fatty acid linked to inflammation that causes increased risk of cardiovascular disease and arthritic changes in joints. Screening for iron and arachidonic acid is available.

What portion of protein intake is from fish low in mercury?

Fish is somewhat of a Catch-22. Large fatty fish often are relatively high in mercury, yet there are health benefits from fish's fatty acids. It has been suggested that about 30 per cent of protein intake should come from seafood low in mercury, such as salmon, oysters, whitefish, sea bass, and sardines. All are a rich source of healthful omega-3 fatty acids.

How often do you get your heart rate up to your age-appropriate target?

It's a good idea to perform at least 30 minutes of sustained aerobic exercise at least three to four days a week. These workouts should increase a person's heart rate to an age-appropriate level, or about 220 beats per minute minus your age. A proper heart rate is essential to improving heart and lung function, and exercise, it seems, can also increase levels of growth hormone, which helps the body repair itself and maintain a good metabolic rate. Growth hormone levels can be screened.

How often do you lift weights?

Muscle strengthening and endurance training two to three times a week, on non-consecutive days, is good for bone strengthening and preventing bone loss.

How many hours of sleep do you get?

Ideally, most people should average seven to eight hours of solid sleep a night - no waking up after three or four hours. Sleep, however, can be disrupted by hormone imbalances. For example, stress during the day results in high cortisol levels to keep you going, but those same levels in the evening cause unwanted "wake-ups" in the night.

Do you snore with silent pauses?

Snoring punctuated by silent pauses in breathing should not happen, and can be symptoms of sleep apnea. If undiagnosed, it can lead to heart disease.

How many times per week do you eat food grilled and charred on a barbecue?

In a perfect world: never. But perfection is difficult (not to mention no fun at all, when we're talking BBQ). Still, limiting grilled meats is a good idea because charred food contains carcinogens that can increase tumours in the gut, particularly in people with a genetic predisposition. It's been suggested that eating meat from the BBQ increases the risk of colon cancer. As with any cancer, the trick is to catch it early. For that, there's a test based on the fact that when colon cancer grows, cells are shed in the stool. PreGen-Plus screens for DNA markers that are associated with the disease and precancerous polyps.

How many days in the week are you in the sun for at least 20 minutes with little to no sunblock?

Everything in moderation. Too much sun, dermatologists warn, can cause skin cancer. But exposure to sunlight, for 20 minutes, before 11 a.m. or after 3 p.m., three to four times weekly, helps the skin produce vitamin D. Without enough of it, bone growth is impeded. Evidence suggests that high levels of vitamin D can protect against some cancers. Where getting enough sun is a challenge, one option is supplements.

Do you have abdominal fat around your waist, or more fat around your hips?

Describe your body shape. Is it an apple or pear? Apple-shaped people are more likely than pear-shaped people to develop health problems related to obesity. The apples among us are also more prone to developing type 2 diabetes, and that shape's been associated with increased risk of hormonal cancers like breast cancer, as well as sleep apnea.

How often do you have a good laugh?

Probably not often enough. Enjoying a good belly chuckle can lower cortisol levels and hence decrease health risks associated with stress.

Maclean's April 30, 2007