Are artificial sweeteners safe?

Sugar is in the spotlight today, not only because of the current obesity epidemic worldwide, but also because of its role in diabetes, cardiovascular diseases, and other health problems.  The World Health Organization (WHO) reiterated its advice recently that added sugar should comprise no more than 10 percent of one’s daily calorie intake, but it also urged consumers that they should ideally strive for half that amount. In the United States, the Food and Drug Administration (FDA), for the first time, is proposing to require food companies to list “added sugar” on the Nutrition Facts label.  That’s because more and more people now consume their calories from sugars not naturally occurring in food — in everything from sodas to snack food, from cereals at breakfast to package entrees at dinner. 

At the same time, there has also been an increased scrutiny of artificial sweeteners as substitutes to sugar.  The Internet is abuzz with unsubstantiated fears linking artificial sweeteners to cancer, seizures, behavioral and cognitive problems, and more.  Questions have also been raised on whether non-caloric sweeteners might somehow nonetheless contribute to weight gain themselves.

So, what’s a person with a sweet tooth to do?  “Safety concerns are out there, of course; many people are worried,” says Susan B. Roberts, PhD, founder of the online iDiet weight loss program (www.theidiet.com). “My take is that there is a lot of hysteria about sweeteners in general, but they have had very extensive testing and the negative results are very few and far between, and usually they are the small underpowered studies in animals that are not repeatable.”

According to the US FDA, “Food safety experts generally agree that there is no convincing evidence of a cause-and-effect relationship between these sweeteners and negative health effects in humans.  The US FDA has monitored consumer complaints of possible adverse reactions for more than 50 years.”  Roberts adds, “Although they seem to be safe, that isn’t to say it is good to guzzle them in unlimited amounts.  A substitute for sugar without going overboard is probably the best thing for health and weight.”

Zero calories

As for concerns that sugar substitutes might not deliver for weight loss, Roberts says, “Although some studies suggest that they might be more hunger promoting, given that sugar has so many calories and sugar is increasingly recognized as unhealthy itself, artificial sweeteners are looking like an increasing good bet for people who are working to control their weight.”

The US 2010 Dietary Guidelines Advisory Committee concluded, “A few observational studies reported that individuals who use non-caloric sweeteners are more likely to gain weight or be heavier.  This does not mean that non-caloric sweeteners cause weight gain; rather, that they are more likely to be consumed by overweight and obese individuals.”

The math is pretty simple:  Each gram of table sugar (sucrose), about one-quarter teaspoon, contains four calories.  A 12-ounce can of non-diet soda, whether sweetened with sugar or high-fructose corn syrup, contains about eight teaspoons of added caloric sweetener, or 128 calories! “Non-nutritive” sweeteners, on the other hand, either pass through the body without being absorbed, contain zero calories, or deliver such intense sweetness that the tiny amounts used contribute essentially no calories.

Sugar substitutes generally don’t raise blood sugar levels, either, so they can be good alternatives for people with diabetes or pre-diabetes.  (“Sugar-free” or “no sugar added” foods, however, are not necessarily carbohydrate-free or lower in carbohydrates.)  Sugar substitutes also have the advantage of not contributing to tooth decay.

Sugar substitutes

Here’s a look at the most common sugar substitutes, including one newly approved by the US FDA, advantame.

1. ACESULFAME POTASSIUM (acesulfame-K, ace-K):  Sold as Sunett and Sweet One,  “ace-K” is a combination of an organic acid and potassium, discovered in 1967.  Ace-K is not broken down by the body and is eliminated unchanged by the kidneys.  Heat stable, it can be used for cooking and baking.

• Sweetness:  200 times sweeter than sugar.

• Regulatory status:  First approved by the US FDA in 1988; approved as general-purpose sweetener in 2003.

• Safety: More than 90 studies support the safety of ace-K in foods and beverages. It has been used extensively for more than 15 years, with no documented health problems in humans.  Several long-term animal studies using doses far higher than any person could consume found no association with increased risk of cancer.

2. ADVANTAME:  This new sweetener is a derivative of aspartame and vanillin. Advantame has zero calories and can be used for cooking and baking.

• Sweetness:  20,000 times sweeter than sugar.

• Regulatory status: Approved by the US FDA in 2014.  Because advantame is so sweet that it is used in tiny quantities, no PKU warning is required (see aspartame).

• Safety: The US FDA reviewed 37 scientific animal and human studies before ruling advantame safe.

3. ASPARTAME:  Sold as Equal and Nutrasweet, aspartame was discovered in 1965.  It consists of two amino acids, phynylalanine and aspartic acid.  Although aspartame contains four calories per gram, its intense sweetness means it is used in small amounts that it contributes virtually zero calories to the diet.  The body breaks down aspartame into its component amino acids, plus a small amount of methanol, which do not accumulate in the body and are less than the amounts from other food sources.  Some loss of sweetness (though no safety concerns) may occur in recipes requiring lengthy heating or baking.

• Sweetness:  180 times sweeter than sugar.

• Regulatory status:  First approved by the US FDA for use in food in 1981; approved as a general-purpose sweetener in 1996.  People who have a very rare hereditary condition called phenylketonuria (PKU) can’t metabolize phenylalanine, and products containing phenylalanine — including aspartame — must carry a warning label.

• Safety:  Aspartame is one of the most widely studied food ingredients of any type.  A 2007 review of the scientific evidence in more than 500 studies and reports over a 25-year span concluded that aspartame does not cause cancer, seizures or adverse effects on cognition or behavior. Although two Italian studies reported a link between aspartame and cancer in rats, the US FDA found “significant shortcomings” in both studies and stated it would not change its position that aspartame is safe. The European Food Safety Authority reconfirmed aspartame’s safety in 2013.

4. NEOTAME: Similar to aspartame, neotame is a derivative of phenylalanine and aspartic acid.  Although neotame is partially absorbed by the body, it is rapidly metabolized and excreted.  It can be used in both cooking and baking.

• Sweetness:  7,000–13,000 times sweeter than sugar.

• Regulatory status:  Approved by the US FDA in July 2002 as a general-purpose sweetener. Because so little is used, neotame does not require a warning for people with PKU.

• Safety: More than 100 studies of neotame have found no negative health effects.

5. SACCHARIN:  Sold as Sweet ‘N Low, Sweet Twin, and Sugar Twin, saccharin is the oldest artificial sweetener, discovered by accident in 1878 during research on coal-tar derivatives.  It is not broken down by the body and is eliminated without providing any calories.  It is heat-stable and suitable for cooking and baking.

• Sweetness:  300-700 times sweeter than sugar.

• Regulatory status:  A 1977 study linking high doses of saccharin (the equivalent of hundreds of cans of diet soda daily in humans) to bladder cancer in rats led to a ban in Canada and a proposed ban in the US.  But the resulting health-warning label on saccharin was removed in 2000, based on a review by the National Technology Program, and the US FDA today considers it safe.

• Safety: Saccharin has been deemed safe by the American Cancer Society, the American Medical Association, and the Academy of Nutrition and Dietetics.

6. STEVIA (Rebaudioside A, Reb-A, rebiana): Sold as A Sweet Leaf, PureVia, Sun Crystals, Steviva, and Truvia, stevia-based sweeteners contain highly purified steviol glycosides, derived from the sweetest part of a plant native in South America. Although metabolized, the components do not accumulate in the body. Stevia sweeteners are heat-stable to almost 400°F.

• Sweetness:  200-300 times sweeter than sugar.

• Regulatory status:  Until 2008, stevia was permitted in the US only as a “dietary supplement.”  Since then, the US FDA has allowed steviol glycosides as general-purpose sweeteners, but is reviewing petitions for other sweeteners derived from the stevia plant.

• Safety:  The joint FAO/WHO Expert Committee on Food Additives concluded that steviol glycosides are safe for use in food and beverages.

7. SUCRALOSE:  Sold as Splenda, sucralose is made by substituting three chlorine atoms for hydrogen-oxygen groups in regular sugar.  The body does not recognize sucralose as a carbohydrate, so it provides no calories and is excreted unchanged.  Heat-stable, sucralose can be used in cooking and baking.

• Sweetness:  600 times sweeter than sugar.

• Regulatory status: The US FDA approved a broad range of uses for sucralose in 1998 and extended approval for its use in all foods and beverages in 1999.

• Safety: More than 100 scientific studies over a 20-year span have found no adverse effects of sucralose in humans.