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A sugary diet may spell trouble for your heart

Don’t let a sweet tooth derail your heart health. Avoid excess sugar from sodas and other sources.

Excess fat and salt are well-known dietary villains, especially when it comes to heart health. But mounting evidence suggests that excess sugar should join the list. Earlier this year, a major study found that a sugar-laden diet may raise your risk of dying of heart disease—even if you aren’t overweight.

“Currently, our dietary guidelines include recommendations for fat and salt but not for sugar,” says Dr. Teresa Fung, adjunct professor of nutrition at the Harvard School of Public Health. But that may soon change. The federal Dietary Guidelines Advisory Committee is considering issuing a new limit for added sugar in its 2015 recommendations, says Dr. Fung. She supports the American Heart Association’s recommendation that women consume less than 100 calories of added sugar per day (the equivalent of about 25 grams or 6 teaspoons) and men consume less than 150 per day (about 37.5 grams or 9 teaspoons). “Added sugar” means not just the sugar you spoon into beverages and onto food, but also the sugar that’s added to many processed foods. It doesn’t include the sugars found naturally in foods, such as fructose in fruit and lactose in milk.

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Sodas and sports drinks

To put that in perspective, a 12-ounce can of regular soda contains about 9 teaspoons of sugar, so quaffing even one a day would put all women and most men over the daily limit.

Sugar-sweetened beverages such as sodas, energy drinks, and sports drinks are by far the biggest sources of added sugar in the average American’s diet. They account for more than one-third of the added sugar we consume as a nation. Other important sources include cookies, cakes, pastries, and similar treats; fruit drinks; ice cream, frozen yogurt and the like; candy; and ready-to-eat cereals.

Added sugars make up at least 10% of the calories the average American eats in a day. But about one person in 10 gets a whopping one-quarter or more of calories from added sugar, according to the study, published in JAMA Internal Medicine. Over the course of the 15-year study, participants who took in 25% or more of their daily calories as sugar were more than twice as likely to die from heart disease as those whose diets included less than 10% added sugar. Over all, the odds of dying from heart disease rose in tandem with the percentage of sugar in the diet—and that was true regardless of a person’s age, sex, physical activity level, or body mass index (a measure of weight that accounts for height).

How sugar harms the heart

Exactly how excess sugar might harm the heart isn’t clear. Earlier research has shown that drinking sugar-sweetened beverages can raise blood pressure. A high-sugar diet may also stimulate the liver to dump more harmful fats into the bloodstream. Both factors are known to boost heart disease risk.

What’s more, sugar delivers “empty calories”—calories unaccompanied by fiber, vitamins, minerals, and other nutrients. Too much added sugar often crowds healthier foods from a person’s diet and also contributes to weight gain.

Could it be possible that sugar isn’t the true bad guy boosting heart disease risk, but that the problem is the lack of heart-healthy foods like fruits and veggies? Apparently not. In the JAMA Internal Medicine study, the researchers measured the participants’ Healthy Eating Index. This shows how well their diets match up to federal dietary guidelines. “Regardless of their Healthy Eating Index scores, people who ate more sugar still had higher cardiovascular mortality,” says Dr. Fung.

To cut sugar from your diet, focus on natural foods, including fresh fruit, to satisfy your sweet tooth. Look for lower-sugar versions of processed food. Trying to curb a soda habit? Mix a little fruit juice with seltzer water as a replacement, says Dr. Fung.

How sweet it is: Sugar labeling terms

What it says

What it means


Less than 0.5 grams of sugar per serving

Reduced sugar or less sugar

At least 25% less sugar per serving compared with a standard serving of the traditional variety of the food

No added sugar or without added sugar

No sugars or sugar-containing ingredients added during processing

Low sugar

Not defined or allowed on food labels

Source: American Heart Association.

Posted by: Dr.Health

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