Pepsi developed Diet Pepsi in 1964 as an alternative to Pepsi-Cola with no sugar and no calories. Artificial sweeteners create the same flavor as the original Pepsi-Cola. While Diet Pepsi contains little nutritional value, people drink it for the light, crisp taste that satisfies thirst.
Diet Pepsi contains no calories per 8-oz. serving. To accomplish this, Diet Pepsi doesn't contain fat, carbohydrates or protein. The carbohydrates are eliminated by using artificial sweeteners that replace the sugar found in traditional Pepsi-Cola.
With the absence of calories, fat, carbohydrates and protein, Diet Pepsi has to get its flavor from somewhere. The ingredients are carbonated water, caramel color, aspartame, phosphoric acid, potassium benzoate, caffeine, citric acid and natural flavors. Each ingredient plays a role in the overall flavor, and potassium benzoate preserves freshness.
Per 8-oz. serving of Diet Pepsi, there are 24 mg of caffeine. Caffeine is found naturally in kola nuts, coffee beans, tea leaves and cacao beans. The amount of caffeine in Diet Pepsi is comparable to one 8-oz. serving of brewed green tea.
Aspartame--an artificial sweetener approximately 180 to 200 times sweeter than sugar--is the primary sweetener found in Diet Pepsi--118 mg per 8-oz. serving. Numerous research studies have tested aspartame's effect on health and the risk for cancer. As of 2010, studies from the National Cancer Institute and the University of Wisconsin-Madison have found no correlation between aspartame and cancer. The National Cancer Institute studied over 500,000 people for more than a decade as they consumed three or more diet soft drinks every day. The results found no increased risk of any type of cancer with consuming aspartame.
Minerals in Diet Pepsi include sodium, potassium and phosphorus. Each 8-oz. serving of Diet Pepsi contains 25 mg of sodium, 20 mg of potassium and 27 mg of phosphorus. Sodium and potassium are electrolytes that regulate body fluids. The phosphorus acts as a preservative to maintain freshness. Diet Pepsi isn't a significant source of other nutrients.