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Sugar and your heart: Sour news about sweets

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Sugar and Your Heart -- Sour News About Sweets

Sugar has always been a target for the "food police," who warn that it leads to tooth decay, diabetes and obesity. So far that's failed to curb America's appetite for sweets. But added sugar is also linked to an increased risk of heart disease. This may make it harder to stay sweet on sugar.

How Sugar Boosts Cardiac Risk

By itself, sugar doesn't harm the heart. But that doesn't mean it's safe. Sugar is bad for you because it increases problems that lead to heart disease. These include:

1. Obesity

Obesity is a complex problem with many causes. Still, there's no denying that excess calories contribute to obesity, and that added sugar is a major source of excess (and empty) calories. Between the 1970s and the 2000s, the average American man's diet added 500 calories a day, more than enough to account for the rise in obesity that occurred during these same years. Fifteen percent of the extra calories comes from sugar, especially sugar-sweetened drinks (soft drinks, fruit drinks, energy drinks, and vitamin water drinks).

2. Diabetes

Type 2 diabetes has increased in parallel with obesity. Sugar-sweetened drinks appear to play an important role. A Harvard study of over 40,000 men linked a high intake of sugar-sweetened drinks to a 24% increase in the risk of type 2 diabetes.

3. Blood pressure

The major dietary cause of high blood pressure (hypertension) is excessive sodium, or salt. Large amounts of alcohol and low amounts of calcium and potassium also play a role. Until recently, sugar has not gotten the blame it deserves. Two major studies should change that.

One linked each daily serving of a sugar-sweetened beverage with a 1.6 mm Hg rise in systolic and a 1.1 mm Hg rise in diastolic blood pressure. The other found that the trend can be reversed. Over an 18-month period, people who cut out just 1 sugary drink a day lowered their systolic blood pressure by an average of 1.8 mm Hg and their diastolic pressure by 1.1 mm Hg. The benefit remained even after the researchers took other factors that affect blood pressure into account. These blood pressure improvements may not seem like much, but in an earlier study of dietary sodium and blood pressure, similar blood pressure reductions reduced the risk of cardiovascular events by 25% to 30%.

4. Metabolic syndrome

Individual cardiac risk factors are bad enough, but combinations are even worse. The metabolic syndrome is just such a cluster of risk factors, and it signals a sharp increase in the risk of heart attack and stroke. A study of 6,039 middle-aged people found that those who averaged more than one soft drink a day were 44% more likely to develop the metabolic syndrome than those averaging less than one soft drink a day.

5. Heart attack

Lots of sugar can increase many cardiac risk factors. But does that translate into actual heart attacks? It does. A 24-year Harvard study of 88,520 people tells the story. People who averaged 1 sugary drink a day were 23% more likely to have heart attacks, compared with people who drank no sugary drinks. Those who had 2 or more sugary drinks per day had a 34% higher risk. The results held up even after researchers accounted for other cardiac risk factors.

How To Cap Your Sweet Tooth

You don't have to give up all sweets to be healthy, but you should limit your consumption of added sugars to about 7% of your total calories. But it's not enough to cut down on table sugar (sucrose). To protect your heart, remember that "natural" or "brown" sugar is no better than white sugar.

When you decide to cut down, sugar-sweetened drinks are the place to start. The average 12-ounce can has 10 teaspoons of added sugar. Because the sugar is in liquid form, it's rapidly absorbed. And the high-fructose corn syrup that's used in so many drinks produces a double whammy. The spike in the blood glucose level triggers a rush of insulin, which increases cardiac risk. In addition, the jolt of fructose stimulates the liver to churn out triglycerides, another bad thing. And some studies suggest that a high intake of sugar may increase oxidative stress and inflammation, which can damage arteries in the heart and other parts of the body.

Here are some ways to help cap your sweet tooth.

  • Give up sugar-sweetened drinks. Instead, quench your thirst with water; ordinary tap water will do just fine. If you really miss soda, switch to non-caloric artificially sweetened brands. Despite early worries generated by animal studies, these appear safe for humans. If you miss the caffeine in energy drinks, take some coffee or tea (easy on the sugar, please).

  • Eat fruit instead of drinking fruit drinks. And don't even worry about making up for the vitamins in vitamin water; your normal diet will provide all the vitamins you need.

  • If you use sweeteners for coffee, tea or cereal, consider artificial sweeteners. They can help you cut down on sugar, but don't rely on them for weight control. That requires a long-term commitment to diet and exercise.

  • Switch up dessert. Instead of a steady diet of cake and pie, experiment with fresh or dried fruit, low-fat yogurt or low-fat frozen desserts that don't have a lot of added sugar.

  • Re-think snacks and treats. Instead of candy or cookies, try fruits, nuts (unsalted, please), yogurt or frozen desserts made without added sugar, or no-sugar-added frozen desserts. Fresh veggies with dip also make a good snack.

  • Read food labels. Try to reduce your consumption of foods with added sugars in any form. Added sugar shows up on food labels as glucose, dextrose, fruit juice concentrates, maple syrup, molasses and high fructose corn syrup.

Sugar has always been part of the human diet, and it always will be. Doctors have no quarrel with naturally sweet foods, but they have important worries about the large quantities of sugar that are added to foods and drinks during manufacturing and processing. Fresh, unprocessed foods are natural and they can help make life healthy and sweet.

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