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Bananas are among foods high in potassium, which is thought to help relax the blood vessels.
Bananas are among foods high in potassium, which is thought to help relax the blood vessels.

Leslie Beck's Food for Thought

How to eat less salt Add to ...

The Heart and Stroke Foundation's 2010 Annual Report on Canadians' health, released last week, made one thing very clear: No one - old or young, male or female - is immune to the threat of heart disease.

The report painted a sombre picture of our nation's heart health. Between 1994 and 2005, major risk factors for heart disease - high blood pressure, Type 2 diabetes and obesity - have skyrocketed among Canadians.

More troubling is the fact that even younger Canadians are experiencing increased risk. Among those aged 35 to 49, the prevalence of high blood pressure rose by 127 per cent. What's more, the number of Canadians in their 20s and 30s with high blood pressure has almost doubled over the past 15 years.

High blood pressure, or hypertension, usually does not cause symptoms. While it may be silent, its effects on your health are not so subtle. Hypertension can cause heart attack and lead to stroke, congestive heart failure, dementia and, over time, kidney disease. Having high blood pressure damages your arteries and increases your heart's workload, causing the heart to thicken and become stiffer.

Blood pressure is the force of blood against the walls of arteries, measured in millimetres of mercury (mmHg).The top number represents the pressure when your heart contracts (systolic) and the bottom number is the pressure when the heart relaxes between beats (diastolic).

Blood pressure that's consistently higher than 140/90 mmHg is considered high. But if you have diabetes, 130/80 is high. Normal blood pressure is below 120/80.

One in five Canadians fall into the category between, called pre-hypertension (130/85 to 139/89). Unless lifestyle changes are made to bring blood pressure down, 60 per cent of people with pre-hypertension will develop hypertension within four years.

Most people diagnosed with high blood pressure have what's called primary or essential hypertension, and the exact cause is unknown. That said, there are several known factors that increase your chances of developing hypertension. Some are within your control, such as diet and smoking. Others, such as genetics and aging, are not.

If you have high blood pressure, the following strategies can help you manage the condition and may reduce the need for medication. If your blood pressure is healthy now, adopting these dietary recommendations can protect you from hypertension.

Lose excess weight

Simply put, as your body weight increases your blood pressure rises too. A larger body mass requires more blood to supply oxygen and nutrients to your tissues, and as more blood is circulated through your blood vessels, the pressure on your artery walls increases.

Even a modest weight loss can reduce blood pressure and dramatically decrease the likelihood of stroke or heart attack.

Reduce sodium

Study after study has linked excess sodium with elevated blood pressure. The problem: Canadians of all ages are consuming salt in excess of their daily requirement.

According to a recent survey commissioned by Dempster's, 70 per cent of Canadians are concerned about the amount of sodium in their diet, but the vast majority don't know the safe upper limit and almost half don't understand sodium numbers on nutrition labels.

From the age of 9 to 50, Canadians require 1,500 milligrams of sodium each day for health.

With age, our bodies become more sensitive to the blood-pressure-increasing effect of sodium, and daily requirements drop to 1,300 milligrams for adults aged 50 to 70 and 1,200 milligrams for people over 70. (Children aged 1 to 3 need 1,000 milligrams a day; 4- to 8 year-olds require 1,200 milligrams.)

For most adults, the daily upper sodium limit is 2,300 milligrams, the amount in one teaspoon of table salt. If you're over 50 or have high blood pressure, you should consume less.

Since 77 per cent of the sodium we consume comes from packaged foods and restaurant meals - not the salt shaker - reading nutrition labels is key to reducing your intake.

Sodium levels vary widely across different brands of similar products. Compare brands and choose one with a lower daily value (DV) for sodium. Foods with a DV of 5 per cent or less are low in sodium. Foods with a DV of 15 per cent or more are high in sodium. (The daily value for sodium on nutrition labels is 2,400 milligrams, slightly more than the safe upper limit.) Compare the serving size listed on the label with the amount you actually eat.

Increase potassium

While the majority of Canadians over-consume sodium, not everyone develops high blood pressure. Potassium, a mineral involved in blood pressure, is one reason why many people don't succumb to hypertension. Studies show that people with a low daily intake of the mineral are more likely to develop high blood pressure and suffer a stroke.

Potassium is thought to help blood vessels relax. A higher intake also causes the kidneys to excrete more sodium, preventing blood pressure from rising.

Adults need 4.7 grams of potassium each day. Excellent sources include bananas, apricots, prune juice, cantaloupe, honeydew melon, spinach, Swiss chard, lentils, black beans, kidney beans, milk and yogurt.

Follow the DASH diet

The DASH (Dietary Approaches to Stop Hypertension) diet emphasizes fruit, vegetables, whole grains and low-fat dairy products - foods high in fibre, calcium, magnesium and potassium, which are linked with lower blood pressure. The diet is also low in refined carbohydrates and saturated fats, which can cause salt retention and raise blood pressure.

In a landmark study published in 1997, individuals with mild hypertension assigned to the DASH diet achieved a reduction in blood pressure similar to that obtained by drug treatment - and without losing weight.

Since then, studies have shown the diet can help lower blood glucose and LDL (bad) cholesterol and raise HDL (good) cholesterol.

To download a copy of the DASH diet, visit http://www.nhlbi.nih.gov/health/public/heart/hbp/dash/new_dash.pdf

Limit alcohol

If you drink, limit yourself to 1 to 2 drinks a day, to a weekly maximum of nine for women and 14 for men. More than two drinks a day will boost blood pressure and increase the risk of developing hypertension.

Leslie Beck, a Toronto-based dietitian at the Medcan Clinic, is on CTV's Canada AM every Wednesday. Her website is lesliebeck.com.

Little salt lickers

Popular types of packaged meals designed for toddlers are often higher in sodium than burgers and fries sold by fast-food chains.



The Canadian Stroke Network has singled out the toddler meals, particularly Nestlé Canada's line of Gerber Graduates Lil' Entrées, for having high levels of sodium that are unhealthy for children and could lead to serious problems down the road.



The association awarded its annual "salt lick" award to Gerber Graduates "Chicken and Pasta Wheel Pick-ups" for having 550 milligrams of sodium - more than half the recommended daily intake for toddlers and the equivalent of two medium orders of McDonald's fries.



But other popular toddler meals don't fare much better. Heinz Toddler Vegetables, Beef and Pasta Casserole has 470 milligrams of sodium per jar, more than Burger King's Double Whopper Jr., which has 430 milligrams.



It's a significant problem because "there is a concern that eating too much sodium in childhood can lead to a preference for salty foods and, consequently, an increased risk of disease as an adult," said Kevin Willis, director of partnerships at the stroke network, in a statement.



Nestlé Canada said it is working on reducing sodium in its Gerber Graduates line, but pointed out that 19 to 33 per cent



of it is in the product's brine, which is not consumed by the child.



However, experts say the food industry needs to make major changes and stop marketing products for babies and toddlers that contain high levels of sodium, sugar and other unhealthy ingredients.



"Why are we getting children to develop a taste for sweet and salty from a very young age to begin with?" said Charlene Elliott, associate professor in communication and culture at the University of Calgary. "A one-year-old isn't demanding that."



Carly Weeks

Follow on Twitter: @lesliebeckrd

 

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