A study published Tuesday in the journal Nature Communications puts forth shocking new claims about the detrimental effects of sugar intake at levels currently considered safe.
Researchers at the University of Utah fed mice a daily diet of 25 percent extra sugar -- the equivalent of a healthy human diet plus three cans of soda. They found that female mice were twice as likely to die and have fewer babies than those on a diet without the added sugar. Males were 25 percent less likely to present normal territorial behavior and reproduce.
Despite this, the mice didn't become obese or demonstrate significant metabolic symptoms. Those effects the researchers did see, however, were just as harmful to the mice's health as being the inbred offspring of two cousins.
The study's senior author, biology professor Wayne Potts, stressed the relevancy of the study to humans. "Our results provide evidence that added sugar consumed at concentrations currently considered safe exerts dramatic adverse impacts on mammalian health," Potts said in a press release. "I have reduced refined sugar intake and encouraged my family to do the same," he added.
The study contrasts with previous research work that involved feeding mice exceedingly large quantities of sugar disproportionate to levels seen in human diets.
Currently, the National Research Council recommends that added sugar should not account for more than 25 percent of a person's diet. That doesn't include the sugar that's naturally in fruits, vegetables or other non-processed food. Thirteen to 25 percent of Americans consume a dose of added sugar equivalent to that used in the study, Potts said.
Dr. Joseph R. Vasselli, Ph.D., a research associate at St. Luke's-Roosevelt Hospital Center and an instructor at Columbia University's Institute of Human Nutrition, called the study "very clever" and "provocative." Vasselli was not involved with the study.
"I think we have to pay attention to the results," he said. Vasselli stressed that he had not studied the paper in depth, but was nonetheless struck by the findings. "They indicate that we need to learn a lot more about what sugar is doing to metabolic mechanisms," he said, adding that followup studies are necessary. At any rate, Vasselli said he would be adding the study to his student lectures in the fall.
Speaking of added sugar -- want to learn more about sweeteners? Here are 12 sweeteners you should know.
Sucrose may sound like something grown in a lab, but it's just everyday table sugar. Sucrose comes in many forms -- granulated, powdered, brown and others -- but chemically, all types of sucrose are two linked monosaccharides: fructose and glucose. When digested, the <a href="http://www.latimes.com/features/health/la-he-sweeteners31-2009aug31,0,7820815.story" target="_blank">link is dissolved and the two monosaccharides are separately absorbed in the small intestine</a>. Most commercially-produced sucrose is derived from sugar beets and sugar cane. One tablespoon of sucrose has <a href="http://www.livestrong.com/article/304073-calories-in-table-sugar/" target="_blank">57 calories</a>.
Glucose and Fructose
Glucose and fructose, when linked, are the simple sugars that make sucrose. But you'll often see them listed separately in the ingredients of products, like sugary sports drinks. Fructose, which also occurs naturally in fruits, is sweeter than glucose. There's also evidence that the two are <a href="http://www.latimes.com/features/health/la-he-sweeteners31-2009aug31,0,2206593,full.story" target="_blank">metabolized differently in the body</a>. As for dextrose? It's just two linked glucose molecules.
The sticky stuff produced by honey bees is a mixture of fructose, sucrose, glucose and water, and it's been used as a sweetener for thousands of years. It's <a href="http://www.latimes.com/features/health/la-he-sweeteners31-2009aug31,0,2206593,full.story" target="_blank">metabolized in roughly the same way as sugar</a> and is <a href="http://www.honey.com/images/downloads/carb.pdf" target="_blank">similarly sweet</a>.
Molasses is a byproduct of sugar refining, most often starting with ingredients like sugarcane and sugar beets. (The molasses made from sugarcane is distinct from that made from sugar beets, but the latter is mainly consumed by animals.) Molasses is mainly composed of <a href="http://www.ncbi.nlm.nih.gov/pubmed/7430034" target="_blank">sucrose, fructose and glucose</a>. One tablespoon of molasses has about <a href="http://caloriecount.about.com/calories-molasses-i19304" target="_blank">58 calories</a>.
Made from the agave plant, agave nectar is about <a href="http://blog.foodnetwork.com/healthyeats/2012/11/01/food-fight-agave-vs-honey/" target="_blank">1 1/2 times sweeter</a> than sugar, which theoretically means you can use less of it. Although it's often compared to honey, it has a <a href="http://www.theglobeandmail.com/life/health-and-fitness/ask-a-health-expert/are-stevia-and-agave-syrup-healthier-sweeteners-than-sugar/article13204159/" target="_blank">thinner consistency</a> and a more neutral taste.
Sucrose is the main sugar in maple syrup, which is made from the sap of maple trees. It has about <a href="http://caloriecount.about.com/calories-syrups-maple-i19353" target="_blank">52 calories</a> per tablespoon.
A ubiquitous sweetener in processed foods, it's composed of glucose and other sugars. Often used as a thickener and sweetener, its popularity in commercial food production has since been surpassed by high fructose corn syrup (which we explain in the next slide). Corn syrup packs roughly <a href="http://caloriecount.about.com/calories-karo-light-corn-syrup-i144571" target="_blank">60 calories</a> per tablespoon.
High Fructose Corn Syrup
Take a stroll down the aisles of your grocery store, and you'll likely find high fructose corn syrup listed as an ingredient for any number of products. It's produced when some of the glucose in corn syrup is <a href="http://www.karosyrup.com/faq.html" target="_blank">converted into fructose,</a> which amps up its sweetness. It's commonly used in foods soft drinks, cereals, condiments and other processed foods. One tablespoon of high fructose corn syrup has roughly <a href="http://www.fatsecret.com/calories-nutrition/usda/high-fructose-corn-syrup" target="_blank">53 calories</a>.
The artificial sweetener aspartame has <a href="http://www.wnho.net/history_of_aspartame.htm" target="_blank">been around since 1965</a>, when a chemist accidentally discovered its sweet flavor. Since then, it's become a popular sweetener for diet drinks, like Diet Coke. It's also been sold in packets under the names Equal, NutraSweet and Canderel. Although the FDA has cleared aspartame as a safe food additive, some <a href="http://www.fda.gov/Food/IngredientsPackagingLabeling/FoodAdditivesIngredients/ucm208580.htm" target="_blank">controversial studies claim the substance is a carcinogen</a>. It has no calories, and is <a href="http://www.cbsnews.com/2100-500165_162-633673.html" target="_blank">160 to 200 times</a> sweeter than sugar.
Although sucralose was <a href="http://www.sucralose.org/facts/default.asp" target="_blank">discovered in 1976</a>, it wasn't <a href="http://www.splenda.com/faq/no-calorie-sweetener" target="_blank">approved for products in the U.S. until 1998</a>. It's made by <a href="http://www.businessweek.com/stories/2005-02-01/how-far-from-sugar-is-splenda" target="_blank">replacing some parts of a sugar molecule with chlorine atoms</a>. The resulting product is <a href="http://www.splenda.com/faq/no-calorie-sweetener#20" target="_blank">600 times</a> sweeter than sugar, but can't be digested by humans, hence its value as a no-calorie sweetener. Sucralose is popularly sold under the brand name Splenda.
The first modern artificial sweetener, saccharine, was originally <a href="http://www.saccharin.org/history.html" target="_blank">synthesized in 1879</a> and became especially popular in the 1960s and 1970s. For decades, it's been sold under the brand Sweet'n Low. Both the substance and the product, however, were delivered a blow in the 1970s when studies suggested that the ingestion of saccharine led to the development of bladder cancer in rats. Saccharine products were required to bear labels warning the public. Later it was learned that the rodents' cancer was caused by a mechanism not present in humans. The <a href="http://www.cancer.gov/cancertopics/factsheet/Risk/artificial-sweeteners" target="_blank">warning label requirement was lifted in late 2000.</a> It's <a href="http://www.cbsnews.com/2100-500165_162-633673.html" target="_blank">300 to 500 times</a> sweeter than sugar.
Stevia, a natural sweetener derived from a species of plants native to South America, Central America and Mexico, is <a href="http://thechart.blogs.cnn.com/2013/07/10/diet-soda-may-do-more-harm-than-good/" target="_blank">250 times</a> sweeter than sugar but has no calories. Like other no-calorie sweeteners, the essential parts of the stevia compound <a href="http://www.globalsteviainstitute.com/en/Default/ResourceLibrary/Articles/MetabolismoftheZeroCalorieSweetenerStevia.aspx" target="_blank">can not be digested</a>. Stevia-derived sweeteners are sold under the brand names Truvia and PureVia. Both <a href="http://www.huffingtonpost.com/2012/09/25/pepsico-stevia_n_1914543.html" target="_blank">Pepsi</a> and <a href="http://www.huffingtonpost.com/2013/06/28/coca-cola-life_n_3516512.html" target="_blank">Coca-Cola</a> have developed Stevia-sweetened sodas.
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