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High blood pressure? Limiting sodium is just part of the solution

We all know that we should cut back on sodium, which can cause high blood pressure, a major risk factor for heart attack and stroke. The other half of the equation is the recommendation that we increase our daily intake of potassium, a mineral that helps control blood pressure, and causes the kidneys to excrete more sodium.

But according to a new study, our neighbours south of the border fail miserably at meeting sodium and potassium guidelines, which could spell trouble for their cardiovascular health. In Canada, we're not doing much better.

Current guidelines suggest that sodium be limited to 2,300 millig rams each day, or 1,500 mg if you're over 50 or have diabetes, high blood pressure, or chronic kidney disease. The recommended daily intake of potassium is 4,700 mg – people with low daily intake have an increased risk of developing high blood pressure or suffering a stroke.

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The study, published online in the American Journal of Clinical Nutrition, is the first to look at how well Americans fare when it comes to jointly complying with sodium and potassium guidelines. It analyzed dietary data for 12,038 men and women over the age of 20. Older adults and people with hypertension, diabetes, and kidney disease were identified.

The results were dismal: Among people advised to limit sodium to 2,300 mg, less than 0.12 per cent met both the sodium and potassium guidelines. In the 1,500-mg sodium group, the guidelines were jointly met by even fewer people – less than 0.015 per cent.

To comply with current guidelines, Americans would need to slash their existing sodium intake by two-thirds and double their potassium intake. Not an easy task, since the consumption of each mineral is tied to one's caloric intake.

For instance, young adults with high calorie needs might eat enough food to get adequate potassium, but may be at risk of over-consuming sodium. Conversely, older adults who require fewer calories may meet sodium recommendations but might not get enough potassium.

A 2011 study from McGill University in Montreal suggests that Canadians are failing at this too. Most Canadians of all ages consumed more than 2,300 mg of sodium each day while daily potassium intakes didn't come close to 4,700 mg for any age or gender group.

According to Health Canada, the average Canadian consumes 3,400 mg of sodium each day – more than double of what our body actually needs (1,500 mg). When I analyze my client's diets, I regularly find that while sodium intake varies, potassium intake is only half of what's recommended.

Potassium-rich foods include potatoes, prune, carrot, tomato and citrus juices, bananas, spinach, Swiss chard, beans, lentils and nuts. Coffee and tea also contribute potassium to your diet, if you drink a few cups a day (eight ounces of coffee contains 110 mg of potassium; eight ounces of black tea contains 88 mg).

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Practice the following tips to help cut back on sodium and double up on potassium.

Reducing sodium

Read nutrition labels. Use the per cent Daily Value ( per cent DV) to get a quick overview of whether there's a little or a lot of sodium in one serving of a food. A food that has a per cent DV of 5 per cent or less is considered low in sodium. A food that has a per cent DV of 15 per cent or greater would be high in sodium. It's not possible to choose all foods with a low per cent DV for sodium. Balance your food choices over the course of the day.

Dine out less often. Thanks to salty ingredients and hefty portion sizes, restaurant meals are often overloaded with sodium. If you eat meals frequently in food courts or chain restaurants, visit the company's website and choose menu items lower in sodium.

Order wisely. When you do eat out, be aware of signs that indicate higher levels of sodium. Try to limit the intake of anything pickled, marinated, smoked, barbequed, or that contains soy sauce, broth, miso, gravy, or bacon. Order dressings, gravies and condiments on the side and use only a little.

Choose unsalted snacks. Instead of pretzels, potato chips and salty crackers, snack on air-popped popcorn with a dash of chili powder, or plain nuts.

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Limit luncheon meats. Ham, sausage, salami and smoked turkey are high in sodium. Bake or grill extra chicken, turkey breast or roast beef when you're making dinner to save as low sodium sandwich fillings.

When possible, choose sodium-reduced or no added salt brands of vegetable juice, soups, and canned vegetables.

Use sodium-laden condiments sparingly. Dips, stir-fry sauces, salad dressings, Worcestershire sauce, barbeque sauce, ketchup and relish all have sodium.

Increasing potassium

Adults need 4,700 mg of potassium each day. Kids aged one to three require 3,000 mg, four to eight-year-olds need 3,800 mg, and teenagers should aim for 4,500 mg per day. Use the chart below to help increase your intake of potassium-rich foods such as fruit, vegetables, legumes, soy foods, nuts and dairy.

Buttermilk, 1 per cent. One cup = 391 mg

Milk, skim. 1 cup = 404 mg

Yogurt, plain, 1 per cent. ¾ cup = 410 mg

Apricots, 4 = 362

½ Avocado = 345 mg

Banana, 1 medium = 422 mg

Cantaloupe, cubed. 1 cup = 440 mg

Dates, 4 = 217 mg

Honeydew, diced, 1 cup = 426 mg

Nectarine, 1 medium = 273 mg

Orange, 1 medium = 237 mg

Orange juice, ½ cup = 262 mg

Prunes, dried, 4 = 245 mg

Prune juice, ½ cup = 373 mg

Raisins, ¼ cup = 275 mg

Spinach, cooked, ½ cup = 443 mg

Sweet potato, baked, 1 medium = 542 mg

Swiss chard, cooked, ½ cup = 508 mg

Tomato juice, ½ cup = 294 mg

White potato, Russet, baked, 1 medium = 952 mg

Winter squash, ½ cup = 214 mg

Black beans, cooked ¾ cup = 452 mg

Chickpeas, cooked, ¾ cup = 353 mg

Kidney beans, cooked ¾ cup = 528 mg

Lentils, cooked, ¾ cup = 540 mg

Nuts, mixed, ¼ cup = 207 mg

Molasses, blackstrap, 1 tbsp = 518 mg

Soybeans, cooked, ¾ cup = 664 mg

Soy beverage, plain, 1 cup = 300 mg

Leslie Beck, a registered dietitian, is the National Director of Nutrition at BodyScience Medical. She can be seen every Thursday at noon on CTV NewsChannel's Direct.

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