I think everyone can agree that soda in general is never a healthy choice on so many levels, but diet soda is even worse.

Diet soda first debuted in 1959 as an alternative for those with diabetes. The first diet sodas were sweetened with saccharin. According to Wikipedia in the United States saccharin is often found in restaurants in pink packets; the most popular brand is “Sweet’N Low“. A small number of soft drinks are sweetened with saccharin, the most popular being the Coca-Cola Company’s cola drink Tab, introduced in 1963 as a diet cola soft drink.

86% of Americans use diet products, including low-calorie, reduced-sugar, or sugar-free foods and beverages. In the U.S., consumers spend about $21 billion per year on these drinks. By comparison, these same consumers only spend $14 billion on organic food.

Precision Nutrition offers this breakdown of diet colas:

Carbonated water

This is water dissolved with carbon dioxide. Poof, we have carbonic acid. While it doesn’t do much for enhancing health (and in fact, it’s part of the process of respiratory excretion as the body tries to rid itself of carbon dioxide), it’s great for getting rid of coffee stains.

Caramel color

Without this, cola wouldn’t be brown and happy hour beers wouldn’t be gold. Caramel color is the most commonly consumed food coloring ingredient in the world. It provides no flavor, only color. It’s produced by heating carbohydrates (like fructose, dextrose, or invert sugar) with a food-grade acid (like sulfuric, phosphoric, or citric) to break the sugar bonds. Or the carbohydrates can be heated along with salts (like ammonium, sodium, and bicarbonate). Polyglycerol esters of fatty acids are also used as anti-foaming agents during the production of caramel color. Think of caramel color as burnt sugar. As you might assume (since it’s used in diet soda), caramel color is soluble in water.

Negative health consequences of caramel color are unlikely as long as someone doesn’t consume more than 200 mg/kg of body weight. Still, there is the potential of an allergic reaction, but that comes with many food ingredients. Caramel color has a very low caloric content, and most of it is not absorbed in the gastrointestinal tract. If you want to know what life would be like without caramel color in diet colas, set your time machine for the early 1990s and get familiar with Crystal Pepsi.

Aspartame

Aspartame, an artificial sweetener that’s composed of aspartic acid, phenylalanine and a methyl ester, is a chemical, not a naturally occurring compound. It was discovered in 1965 by a chemist named G.D. Searle. He was actually studying a treatment for gastric ulcers at the time. 16 years later, aspartame received limited sanction, and in 1983 was approved for use in diet sodas. It’s the most popular sweetener in the U.S. food industry (as of 2007). With more than 90 countries having approved aspartame, its use is widespread. Brand names for aspartame include Equal, NutraSweet and Tri-Sweet.

A study on patients with disordered eating found them consuming up to forty diet sodas (12 ounces each), 30 pieces of sugar free gum, and up to 350 packets of artificial sweetener per week.

Research in animals provides evidence that aspartame has a strong cancer causing and brain damage potential, with the dosage tested approximated at the ADI for humans. Human research shows that consuming 2 to 100 mg/kg of aspartame doesn’t influence cognition and behavior.

Aspartame has 92 side effects listed by the FDA and use by pregnant women and young children is discouraged. Hmmm, if it’s not safe enough for the pregnant mom down the street, is it safe enough for everyone else?

Phosphoric acid

This stuff has a tangy, sour taste and slows the growth of mold and bacteria. It’s a bit different from straight phosphorus as it binds with magnesium and calcium in the digestive tract to form salts that aren’t absorbed. This may lead to a decline in the materials needed for bone deposition. So as you might assume, studies have associated phosphoric acid consumption to a lower bone density. Still, other studies have found that phosphoric acid has no impact on calcium excretion.

Diet colas, which generally contain phosphoric acid (non-colas usually don’t), have also been linked to kidney disease and kidney stones. Two or more colas per day more than doubled the incidence of kidney disease in one study; non-colas didn’t have the association. While phosphoric acid doesn’t do much to improve our health, it’s exceptional for removing rust from iron and steel tools.

Potassium benzoate

This stuff is a preservative and discourages the growth of yeast, mold and bacteria. It has minimal taste and risk for toxicity. Unfortunately, along with ascorbic acid (vitamin C), potassium benzoate can form benzene. Benzene is a known carcinogen. Sodium benzoate is also used in some diet sodas, but since most people don’t want the extra sodium, manufacturers are using it less. While potassium benzoate doesn’t do much to improve our health, it’s great for pyrotechnic whistle noises in fireworks.

Natural flavors

Well, the magical natural flavor used to be saskra root in diet coke, but that plant is now extinct. With that being said, natural flavors can include countless items. I received the following statement from The Coca-Cola Company after inquiring about the natural flavors they use:

Thank you for contacting The Coca-Cola Company, Mr. Andrews. We appreciate your interest in Diet Coke.

As you may know, flavor formulations are very valuable proprietary information, therefore we do not discuss the blend of flavoring materials used in Coca-Cola brand products. However, consumers can be assured that all flavors used in brands of The Coca-Cola Company are recognized as safe and suitable for use by the local regulatory officials in the countries in which they are sold.

Additionally, the U.S. Food and Drug Administration (FDA) regulates the substances that can be labeled as flavors, whether natural or artificial, and we strictly adhere to all such guidelines. If you would like to learn more about the FDA standards relating to flavors, they can be reached at www.fda.gov or by phone at 1-888-INFO FDA.

We hope this information is helpful. If you have additional questions or comments, please feel free to contact us again.

Gisele
Industry and Consumer Affairs
The Coca-Cola Company

Citric acid

More than half of all citric acid is produced in China. It acts as a preservative and provides a sour taste. Too much of it can erode tooth enamel. While it does exist naturally in citrus fruits, this isn’t where most “food grade” citric acid comes from. Actually, cultures of something called Aspergillus niger are fed on a sugar containing medium to produce it. Aspergillus is a mold found growing on starchy food crops.

While citric acid doesn’t do much to improve our health, it’s great as an additive in bathroom cleaners.

Caffeine

Caffeine is the most widely consumed stimulant in the world and occurs naturally among several plants such as coffee bean, kola nut, tea leaf, and cacao seed. Caffeine is a methylxanthine. Other common methylxanthines include theobromine and theophylline, which are found in cocoa and teas. Methylxanthines act as adenosine receptor blockers and phosphodiesterase inhibitors. If you have no idea what I just said, here’s some further explanation. Adenosine acts as the “brakes” in the central nervous system. So when its effects are blocked (by caffeine), stimulation occurs.

Caffeine is actually one of the most widely studied, and most effective, ergogenic acids on the planet. However, its purpose in diet soda is likely for immediate stimulation and it offers the potential for dependence.