Plug the word "sugar" into an Internet search engine, and you will receive a wealth of conflicting information. Some say that an excess of sugar in the diet causes obesity; others say it's due more to saturated fat. Concerned citizens and scientists blare warnings about high-fructose corn syrup, while food manufacturers claim it's no different than table sugar. Nutritionists advise eaters to limit sugar in the diet, but fail to mention which ones or by how much. No wonder people are so confused about sugar! This article will examine different issues regarding sugar and attempt to clear up the confusion for dieters and healthy eaters alike.
Fat vs. Sugar
First of all, not all fat and sugar is inherently unhealthy. Certain types of both fat and sugar are important elements in a healthy diet. But in the debate over which is more detrimental, sugar definitely wins. While some naturally occurring sugars provide the body with needed energy, most sugar--especially added sugar--is simply a source of excess calories with no nutritive value. Healthy fats (i.e. mono- and polyunsaturated), on the other hand, possess rich dietary value and can even prevent disease when consumed in recommended amounts.
However, separating the bad sugars from good on a food label is no easy task. While bad fats (i.e., trans fat and saturated fat) are easy to identify on food labels, there's no such distinction in labeling for sugars. Sugars such as glucose and fructose occur naturally in foods, but added sugars often have similar or bizarre names. Also, grams of naturally occurring sugar are counted with grams of added sugar and expressed as total sugar content on food labels. This can cause confusion when trying to choose healthy foods. It doesn't help that sugar appears in almost everything: cereal, yogurt, fruit juice, candy, and even bread. What's really disturbing is that many processed foods labeled 'low-fat' use added sugars to enhance flavor while adding dozens of empty calories, leading people to not only consume more calories, but to eat more food to feel full.
Excess intake of both fat and sugar can lead to obesity and heart disease, but excess sugar can also cause diabetes, a disease that affects 24 million Americans, and other metabolic problems. Healthy eaters should be careful to limit both fat and sugar, but sugar most especially.
Natural Sugar vs. Added Sugar
Some weight-loss gurus go so far in advising clients to limit sugar that they suggest abstaining from fruit, which contains fructose, a sugar much sweeter than glucose. However, the fructose content of fruit is relatively low and chemically different from added sugar, making it easier for the body to process--not to mention that fruit is high in fiber and contains essential vitamins and nutrients. The real dietary culprit is added sugar, which is not only highly sweet and caloric, but it is added to foods in amounts far greater than what occurs naturally. Added sugars have no dietary benefits and should be avoided. The American Heart Association (AHA) recommends limiting added sugar intake to 100 calories (6 teaspoons) a day for women and 150 calories (9 teaspoons) a day for men. To put that into perspective, a 12 oz. soda contains 8 teaspoons of added sugar. The AHA estimates that American adults currently consume 22 teaspoons of added sugar a day.
Glucose vs. Sucrose and Fructose
Glucose, sucrose and fructose are all types of sugars, but they are not the same. Glucose is the natural sugar found in carbohydrates and other foods. Fructose is the natural sugar found in fruit. Sucrose, however, is simply another name for table sugar. Sucrose contains equal parts of glucose and fructose. What differentiates these sugars is how they are processed by the body.
- Glucose metabolism - carbohydrates enter the body and are broken down into glucose. The liver releases insulin to balance the body's blood sugar level, and various organs (including muscles) take up the glucose to fuel important body processes. Leftover glucose is stored in the liver for future energy needs or converted to fat.
- Fructose metabolism - fructose enters the body and stimulates a complex metabolic response in the liver, which then processes all of the fructose, converting most of it to fat and storing it in fat cells. Almost no insulin is produced to regulate blood sugar except when glucose is present. Very little fructose is used for energy, since it cannot be metabolized by most of the body's other organs like glucose can.
High-Fructose Corn Syrup (HFCS) vs. Table Sugar
In recent years, HFCS has come under serious scrutiny as a possible major contributor to obesity, though others claim it is no more detrimental than any other added sugar. Like table sugar, HFCS contains both glucose and fructose. It's used in food because it tastes sweeter than table sugar and can therefore be used in smaller quantities as a sweetener. However, there are two major differences between these added sugars. The first is the concentration of fructose in HFCS. While table sugar is half glucose and half fructose, HFCS often contains 55 percent fructose. Though a relatively small difference in percentage, the body's metabolic processing of fructose means a greater percentage of the syrup will be quickly converted to fat.
Secondly, researchers at Princeton discovered that HFCS also contains a type of large sugar molecule not found in table sugar, and is chemically different as well. In table sugar, the fructose molecules are bound to the glucose molecules, requiring an additional step to metabolize. However, the molecules in HFCS are not bonded, which causes the fructose to overwhelm the liver and be converted to fat even faster. In a controlled six-month study, Princeton researchers gave water sweetened with table sugar to one group of rats and water sweetened with HFCS to another group. The group that consumed HFCS gained abnormal amounts of weight and developed fatty tissue around their mid-sections, even though the concentration of HFCS used was far less than that of the table sugar.
The Corn Refiners Association, the people who produce HFCS for use in processed foods, say that to single out HFCS for criticism is unfair, considering that consuming excess table sugar also leads to unhealthy weight gain, and some HFCS contains only 45 percent fructose. They are petitioning the FDA to allow them to change the HFCS label to "corn sugar." But how do consumers know when HFCS or "corn sugar" contains 45 percent fructose or 55 percent? Answer: they don't.
Added Sugar vs. Artificial and Nutritive Sweeteners
Sadly, the debate over artificial sweeteners is still ongoing. The FDA and most reputable health organizations consider no-calorie artificial sweeteners to be safe and preferable to table sugar because they contain no calories and are not metabolized by the body. Artificial sweeteners are either produced synthetically or derived from highly processed sugar or plants, and are much sweeter than table sugar.
Some people claim that the concentrated sweetness of artificial sweeteners causes people to crave more sugar and overeat. Others say that synthetic sugars are dangerous and cause ill health effects. However, research in the area remains inconclusive.
Another alternative to table sugar and corn syrup is known as a nutritive sweetener. These are naturally occurring substances that not only contain natural sugars, but also healthy nutrients. Honey and agave are two of the most popular, and great alternatives for people wishing to avoid the empty calories of table sugar and the nutrient-void chemicals of artificial sweeteners.
Solution: Check Food Labels
Want to know if your favorite food contains added sugar? Just read the list of ingredients on the food label. If you see any of these or ingredients ending in -ose, added sugar is present. Also, the further up sugar is listed on the label, the more prevalent it is in the food. Naturally occurring sugars (like glucose) aren't listed with the ingredients.
Sources
- American Diabetes Association. "The American Diabetes Association Encourages Community Organizations to Join the Movement to Stop Diabetes." Press Room. American Diabetes Association, 8 Mar. 2010. Web. 3 June 2011.
- American Heart Association. " Sugars and Carbohydrates. " American Heart Association, Inc., 2011. Web. 3 June 2011.
- --" Fats 101." American Heart Association, Inc., 2011.
- Associated Press. "Cut back, way back, on sugar, says heart group." MSNBC.com, 24 Aug. 2009. Web. 3 June 2011.
- Elliott, Sharon S., et al. " Fructose, weight gain, and the insulin resistance syndrome." American Journal of Clinical Nutrition 76.5 (2002): 911-922. Web. 3 June 2011.
- Harvard School of Public Health. "How to Spot Added Sugar on Food Labels." The Nutrition Source. Harvard University, 2011. Web. 3 June 2011.
- Knowles, David. "CRA Petitions FDA for Use of "Corn Sugar." Corn Refiners Association. SweetSurprise.com. Sept. 14, 2010. Web. 3 June 2011.
- Mayo Clinic staff. "Artificial sweeteners: Understanding these and other sugar substitutes." Nutrition and Healthy Eating. Mayo Foundation for Medical Education and Research (MFMER), 2011. Web. 3 June 2011.
- Parker, Hilary. " A sweet problem: Princeton researchers find that high-fructose corn syrup prompts considerably more weight gain." Web Stories. News at Princeton. Princeton University, 22 Mar. 2010. Web. 3 June 2011.
- Paskin, Janet. "Fat is where it's at." Ode Magazine USA, Inc., June/July 2009. Web. 3 June 2011.
- ScienceDaily. "Fructose Metabolism More Complicated Than Was Thought." Science News. ScienceDaily LLC, 11 Dec. 2008. Web. 3 June 2011.
April Kelsey - April Kelsey is a freelance writer specializing in politics, academic writing, and nutrition.
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