Skip to content

How Sugar Can Really Break Your Heart

Everything we thought we knew about nutrition and heart health may be wrong. Experts around the world are now looking at an unexpected culprit as the main cause of heart disease: sugar.

We've heard it so many times, it comes as naturally as looking both ways before you cross the street: Protecting your heart means cutting down on fatty, salty foods.

It's a mantra made manifest by the easy-to-understand concept of blobs of fat floating about our bloodstream, and by the vision of heart-unhealthy public figures like Dick Cheney and pre-vegan Bill Clinton, towering symbols of political striation and enthusiastic cheeseburger consumption. But while your cardiologist is unlikely to be passing around gift certificates to the Cheesecake Factory, more and more heart experts are coming to realize that fat and salt are only part of the story. The real danger to our hearts may be sneakier. And sweeter.

For the first time, scientists have linked the amount of sugar in a person's diet with her risk of dying from heart disease. People who ate between 17 and 21% of their calories from added sugar had a 38% higher risk of dying from heart disease, compared with people who consumed 8% or less of their calories from added sugar, according to a study recently published in the Journal of the American Medical Association.

The case against sugar is so compelling that last year the advisory panel that helps create the U.S. Dietary Guidelines eased up on its hardline stance against fat and cholesterol, recommending instead strong limits on added sugar (the government will release the official guidelines later this year). The group suggested that Americans limit added sugars to no more than 10% of daily calories (that's 12.5 teaspoons for someone with a 2,000-calorie diet). The American Heart Association takes an even tougher position, recommending no more than 100 calories per day from added sugars or 6 teaspoons for women, and 150 calories (9 teaspoons) for men. On average, we now get 22 teaspoons per day.

But what exactly is "added sugar," and why do experts suddenly believe that it's a threat to your heart?

Sugar Shakedown

When they talk about sugar, heart experts aren't talking about the stuff that we consume from eating whole foods. "Added sugars are contributed during the processing or preparation of foods and beverages," says Rachel K. Johnson, Ph.D., RD, professor of nutrition at the University of Vermont. So lactose, the sugar naturally found in milk and dairy products, and fructose, the sugar that appears in fruit, don't count. But ingredients that are used in foods to provide added sweetness and calories, from the much-maligned high-fructose corn syrup to healthier-sounding ones like agave, date syrup, cane sugar, and honey, are all considered added sugars.

But aren't all sugars created equal? Not really, say experts. Even if added sugars and natural sugars are chemically similar, it's more about the total package. Fructose, the sugar in fruits, seems to be the most problematic health-wise; however, it's generally considered to be harmful only in high concentrations. "It's almost impossible to overconsume fructose by eating too much fruit," says Johnson. Consider this: You'd need to eat five cups of strawberries to get the same amount of fructose as in one can of Coke.

Another major difference—the fiber in fruit helps to fill you up, slow down digestion, and prevent rapid blood sugar spikes. What's more, the fruit is also a rich source of disease-fighting vitamins and antioxidants. Here's what you do want to limit: Fruit juice, which is devoid of fiber and leaves you with too much sugar and too little satisfaction. It also couldn't hurt to moderate your portions of dried fruit, which is also easy to overdo—about 1/4 cup is considered a serving size.

Bottom line: You don't need to be afraid of a mango. That pumpkin spice latte is a whole other story.

A Spoonful of Trouble

You already knew the stuff wreaks havoc on your teeth and isn't doing anything to help your diabetes risk. Plus, those added calories are only adding to your waistline, without providing any substantial nutritional value in return. But did you know that added sugar:

Increases your blood pressure

Sugar may be worse for your blood pressure than salt, according to a paper published in the journal Open Heart. Just a few weeks on a high-sucrose diet can increase both systolic and diastolic blood pressure. Another study found that for every additional sugar-sweetened beverage, the risk of developing hypertension increased 8%. Too much sugar leads to higher insulin levels, which in turn activate the sympathetic nervous system and leads to increased blood pressure, according to James J. DiNicolantonio, PharmD, a cardiovascular research scientist at Saint Luke's Mid America Heart Institute in Kansas City, Missouri. "It may also cause sodium to accumulate within the cell, causing calcium to build up within the cell, leading to vasoconstriction and hypertension," he says.

Messes with your cholesterol

Eating a diet high in added sugar can do a number on your blood lipid levels, according to a 2010 study published in the Journal of the American Medical Association. Adults who ate the most added sugar (an average of 46 teaspoons per day!) were more than three times as likely to have low good HDL cholesterol levels compared with people who kept the sweet stuff to a minimum, according to researchers at Emory University who analyzed the blood of more than 6,000 men and women. The scientists also found a link between eating more added sugar and an increased risk of elevated triglycerides.

Strains your heart muscle

"Americans have increased their calorie intake over the past 30 years primarily in the form of carbohydrates and sugars," says Johnson. And those 256 extra calories per day we consume in the form of added sugar are likely leading to weight gain, which may directly damage the heart, according to new research. Obese adults have elevated levels of an enzyme that indicates injured heart muscle, found researchers at Johns Hopkins University—demonstrating that long before a heart attack may occur, those carrying extra weight are experiencing damage directly to their hearts. And you don't have to be gravely overweight for the damage to occur—the risk rose incrementally with BMI.

sugar and heart disease

Shake the Sugar

Reducing the amount of added sugar can't be that hard—can it? Well, certain high-sugar foods are obvious—Dr. Pepper, Twizzlers, and Ben & Jerry's, natch. But an even bigger problem may be the sneaky sugar lurking where you least expect it. "It's in everything—even seemingly healthy foods like salad dressing, whole-wheat breads, and tomato sauces," says Brooke Alpert, RD, owner of B Nutritious and author of The Sugar Detox. What's more, it's impossible to find out how much added sugar a food contains by looking at the nutrition facts panel, since labels don't distinguish between added sugars and naturally occurring ones.

So what can you do to cut the sugar? Here are six steps.

1. Read Labels

"There are more than 70 different names for sugar," says Alpert. Scour the ingredients list on any packaged food you buy for words like sucrose, barley malt, beet sugar, brown rice syrup, agave, and cane juice.

2. Buy Plain

Flavored foods are often code for "sugar added." If strawberry flavored Chobani yogurt packs 15 grams of sugars, there's no way to tell how much is from added sugars and how much is from the naturally occurring lactose. Stick with the plain version, and it will be easy to see that all 4 grams of the sugars are supposed to be there. Add flavor with whole fruit—or really shake up your taste buds with a savory topping instead. "It's the same idea as ordering dressing on the side. This way, you get to be in control of how much sweetness is added to your food," says Alpert. (Here are our 6 Fat-Burning Ways to Eat Yogurt.)

3. Drop Drinkable Sugar

"Almost half of Americans' added sugars intake comes from drinks," says Johnson. So for many people, limiting beverages like soda, iced teas, lemonade, and fruit punch is a simple way to cut back big time. And healthy-sounding drinks like kombucha and vitamin waters are no exception. Don't forget about your Starbucks run, either, says Alpert. "Coffee and tea aren't supposed to be dessert." Try one of these 14 Detox Waters instead.

4. Skip Juices and Smoothies

Without fiber to buffer the sugar load, the natural fructose in, say, an orange, is a very different animal. A cup of juice can be equivalent to about four oranges—an amount you'd be pretty unlikely to eat in whole-fruit form. As for smoothies, they're a step in the right direction since they contain the whole fruit—but research from Purdue University found that liquid calories aren't as filling as chewable ones. And by blending fruit into a pulp, it's easy to get more fructose than you're bargaining for.

5. Cut the Condiments

Add-ons like ketchup, barbecue sauce, flavored vinegar, and some mustards (like honey mustards) can be loaded with sweetener. If you're going to dress up your meal, read labels to be certain there are no surprises—Dijon mustard, apple cider vinegar, and hot sauce are usually good options. Or use produce: Pineapple salsa, Vidalia onions, and tomatoes are all simple additive-free ways of sweetening a plate.

6. Add Herbs, Spices, and Extracts

They're flavorful and low-calorie additions to any meal. "Cinnamon, vanilla, ginger, and nutmeg are some of my favorite "sweet" spices," says Alpert, who recommends adding them to oatmeal, yogurt, or even nuts. "Bonus point—a lot of spices also help regulate your blood sugar levels and can even reduce the amount of AGEs (advanced glycated endproducts) that result from too much sugar in your bloodstream," she adds. For more ideas, check out our report on the 5 Best Spices for Fat Loss.

From the Fall 2015 issue of Eat This, Not That! Magazine. 

MELT UP TO 10 POUNDS IN ONE WEEK! WITH OUR BEST-SELLING NEW DIET PLAN, The 7-Day Flat-Belly Tea Cleanse! Test panelists lost up to 4 inches from their waist! Available now for Kindle, iBooks, Nook, Google Play, and Kobo.

7-Day Flat Belly Tea Cleanse by Kelly Choi

Eat This, Not That!
Inspired by The New York Times best-selling book series, Eat This, Not That! is a brand that's comprised of an award-winning team of journalists and board-certified experts, doctors, nutritionists, chefs, personal trainers, and dietitians who work together to bring you accurate, timely, informative, and actionable content on food, nutrition, dieting, weight loss, health, wellness, and more. Read more about Eat This
Filed Under