The Dangers of Soda and Other Sugary Drinks

They turn into fat—fast

A typical healthy person has about 5 grams of glucose, a form of sugar, circulating in his or her blood. A 20-ounce bottle of cola contains 65 grams of sugar—five times as much as a typical glazed doughnut. When you drink a sugary beverage, it enters your bloodstream and raises your glucose levels very quickly — far faster than if you took in the same number of calories from a solid food. When your body suddenly has more blood sugar than it can use for energy, it converts this excess glucose into body fat.

Worse, even though sugary beverages are loaded with calories, your brain doesn’t recognize drinks as food. “Calories in liquid form do not really produce satiety,” Li says. So even as it floods you with sugar, a soda won’t trigger the hormones that tell you to stop eating.

They come dressed as ‘healthy’

The belief that certain drinks are “healthy” can cause people to forget about their sugar content, says Tim Spector, M.D., professor of genetic epidemiology at King’s College​London. “A great example of this is store-bought orange juice,” he adds. “It’s an ultra-​processed food and has as much sugar as [soda]. And, for some people, it can cause the same sugar spikes.” Same goes for sweetened coffees, fruit smoothies or sports drinks, which can contain 34 grams of sugar in a 20-ounce​bottle. The American Heart Association recommends adults consume no more than 6 teaspoons (25 grams) of added sugar per day for women (9 teaspoons, or 36 grams, for men). And that includes all the sugars snuck into the breads, sauces and prepared foods you eat.

They may shorten your life span

If the threat of diabetes and obesity weren’t scary enough, long-term consumption of sweet beverages may also increase your risk of dying from heart disease and certain cancers. Harvard researchers found sipping drinks sweetened with sugar to be associated with a moderately higher risk of breast cancer or colon cancer. They also discovered that for every additional sugary drink a person consumed, on average, per day, the risk of dying from​heart disease increased by 10 percent.