Nutrition

Sugar: The Science Behind Your Sweet Tooth

It’s 2 o’clock in the afternoon and you’re feeling a little sleepy after lunch. Instinctively, you reach for that soda or piece of candy. Something tells you that maybe you shouldn’t, but you do anyway. You’re not alone in this.

Like millions of Americans, you probably rely on a quick sugar high to get you through the day, but too much sugar can take a toll on your health and fitness goals. In this article, we explain the difference between good and bad sugars, and why it’s important to keep an eye on your sugar intake.

Why you crave sugar

Sugar is an addictive substance that triggers dopamine release in the brain, leading to feelings of pleasure. In one study, when mice were offered a sugar solution and their normal food after a fasting period, they chose to drink the sugar solution as soon as it was offered. In this experiment, the animals showed behaviors similar to the effects of drug abuse — going through binging, withdrawal, and craving while on this feeding schedule.

Unfortunately, sugar’s addictive qualities and the prevalence of sugar in American diets is taking a toll on our health and well-being. While sugar naturally occurs in many foods, such as fruits, it’s added sugars that raise concerns. Added sugars include all sugars used as ingredients in processed and prepared foods such as breads, cakes, soft drinks, jams, chocolates and ice cream, candy and table sugar. More shocking sources include sauces, yogurt, peanut butter, canned vegetables, and salad dressing.

How much sugar you should consume

Some helpful guidelines on sugar consumption were recently issued by the Food and Drug Administration (FDA). Americans should limit added sugar to no more than 10 percent of daily calories. For an adult, that means consuming no more than 12.5 teaspoons (or 50 grams) of added sugar a day, the equivalent of the amount of sugar in a can of Coke.

Different kind of sweetness

Sure, sugar may have a bad rep, but there are differences in the type of sugar out there. Chemically, sugar is made up of glucose and fructose. There’s not one type of sugar that is better or worse for you. Too much of any type of sugar will ultimately lead to gain weight. The difference is that fructose and glucose affect your body differently and are metabolized differently.

  • Fructose, the main sweetener in soda and juices, can only be metabolized by the liver and is not necessary for survival. The bottom line: When we consume more fructose than our liver can process, fructose is turned into fat, contributing to weight gain.
  • Glucose, on the other hand, can be metabolized by nearly every cell and requires a release of insulin into the bloodstream in order to be completely metabolized. Studies examining the effects of glucose vs. fructose found that both kinds of sugars caused weight gain when consumed in excess, although fructose was more commonly linked to a higher risk of heart attack and stroke.
  • Sucrose (sometimes called saccharose) is the combination of both fructose and glucose.

Most fruits have between 40-55 percent fructose and table sugar (sucrose) has about 50 percent fructose. But just because fruit and table sugar have a similar composition doesn’t mean that they should be interchangeable. Fruits contain important vitamins, antioxidants, and water and tend to have less sugar by volume, while snacks like cookies and candy typically contain more contain more sugar without the nutrition value. For example, one half a cup of strawberries contains 3.7 grams a sugar, while one half a cup of ice cream contains 14 grams.

Processed sugar

Although all sugars are technically “natural,” most of the ones that we consume today are refined. The refining process removes most essential nutrients which leaves you with nothing but calories. Even sugars from agave cacti, sugar cane, maple trees, coconut palms, corn, or sugar beets are processed and have little nutritional value and actually make you feel hungrier faster. The reason for this is because refined sugar is digested more quickly than sugar found in fruit. The fiber in fruit also slows down the digestion of sugar and makes you feel more full.

Examples of processed or added sugars include:

  • White or table sugar (sucrose) comes in those little white sugar packets that you get with your coffee at restaurants across the nation.
  • High fructose corn syrup, a corn-based sweetener, is one of the most common sweeteners in processed American foods today (it’s a cheaper replacement to table sugar), contributing to one of the most significant changes to our food supply in the century.
  • Agave syrup is often advertised as a healthy — or natural — alternative to table sugar as it has a lower glycemic index (a measure of how quickly a food is broken down to glucose in the body). However, agave syrup is actually very high in fructose, meaning that it goes almost immediately to the liver, and any fructose that isn’t needed will turn into fat.
  • Brown rice syrup (malt) is derived by cooking down rice starch and is readily available in stores as maltose or maltose syrup. It has a higher glycemic index than table sugar.
  • Maple syrup and pancake syrup are considered added sugars because they are actually processed.
  • Other sugars that may be lurking in processed foods include fructose sweetener, liquid fructose, honey, molasses, anhydrous dextrose, crystal dextrose, and dextrin.

Naturally occurring sugars

Whenever possible, choose foods that contain naturally occurring sugars in their native forms, such as whole fruits and vegetables. However, beware that even though some foods contain sugar naturally, their high sugar content can lead to weight gain if not consumed in moderation. Examples of fruits and vegetables with higher sugar levels include dried fruits, lychees, figs, mangoes, cherries, and grapes. Lower sugar ones include avocados, raspberries, blackberries, and strawberries.

Sugar levels in common foods

According to FDA Nutritional Information on Raw Fruits and USDA National Nutrient Database, these are the average sugar levels in commonly eaten foods in the American diet.

 

how much sugar in food infographic

 

Artificial sweeteners

There are naturally occurring sugars, added sugars, and artificial sweeteners too. Artificial sweeteners, such as aspartame, saccharin, and sucralose, are chemically manufactured molecules that do not exist in nature. Found in sodas, candy, canned and packaged foods, people often turn to sugar substitutes when trying to reduce sugar in their diet. Even though these synthetic sugar substitutes don’t add calories to your diet and have been generally recognized as safe by the FDA, they have been scrutinized for causing health problems, including cancer.

When you have artificial sweeteners, your body thinks you’re about to ingest real sugar and starts releasing insulin. High levels of insulin can cause your body to store fat. Artificial sweeteners may also cause changes in your gut bacteria, leading to more inflammation and increase blood sugar levels, ultimately leading to more cravings. Your best bet is to steer clear of artificial sweeteners as much as possible.

3 reasons sugar is bad for you

  • Weight gain and obesity: Numerous studies have shown that increased consumption of sugar, especially in liquid form, contributes to weight gain. The more you consume, the greater your chances of health problems.
  • Heart disease: Increased sugar consumption was also shown to correlate with a significant increase in cardiovascular disease. In a 15-year study, those who consumed 25 percent or more of their calories from sugar were twice as likely to die from cardiovascular disease compared with those who consumed less than 10 percent of calories from sugar.
  • Dental health: Tooth decay is another downfall of eating too much sugar. Sugar consumption causes excessive acid to form, which then enhances the damage to your enamel caused by the bacteria in your mouth. That’s when cavities occur.

Moderation is key

If you want to live a disease free life and maintain a healthy weight, simply cutting out added sugars can make a huge difference. What it all comes down to is moderation and knowing yourself. If you are the type who gets a taste of sweetness, and spiral into sugar oblivion, consider taking a break.