Saccharin

Saccharin, also called saccharine, benzosulfimide, or E954, or used in saccharin sodium or saccharin calcium forms, is a non-nutritive artificial sweetener. Saccharin is a sultam that is about 500 times sweeter than sucrose, but has a bitter or metallic aftertaste, especially at high concentrations. It is used to sweeten products, such as drinks, candies, baked goods, tobacco products, excipients, and for masking the bitter taste of some medicines. It appears as white crystals and is odorless.

Saccharin derives its name from the word "saccharine", meaning "sugary". The word saccharine is used figuratively, often in a derogative sense, to describe something "unpleasantly over-polite" or "overly sweet". Both words are derived from the Greek word σάκχαρον (sakkharon) meaning "gravel". Similarly, saccharose is an obsolete name for sucrose (table sugar).

Saccharin is heat-stable. It does not react chemically with other food ingredients; as such, it stores well. Blends of saccharin with other sweeteners are often used to compensate for each sweetener's weaknesses and faults. A 10:1 cyclamate–saccharin blend is common in countries where both these sweeteners are legal; in this blend, each sweetener masks the other's offtaste. Saccharin is often used with aspartame in diet carbonated soft drinks, so some sweetness remains should the fountain syrup be stored beyond aspartame's relatively short shelf life.

In its acid form, saccharin is not water-soluble. The form used as an artificial sweetener is usually its sodium salt. The calcium salt is also sometimes used, especially by people restricting their dietary sodium intake. Both salts are highly water-soluble: 0.67 g/ml in water at room temperature.

In the 1970s, studies performed on laboratory rats found an association between consumption of high doses of saccharin and the development of bladder cancer. However, further study determined that this effect was due to a mechanism that is not relevant to humans (deposition of crystals; see § History section). Epidemiological studies have shown no evidence that saccharin is associated with bladder cancer in humans. The International Agency for Research on Cancer (IARC) originally classified saccharin in Group 2B ("possibly carcinogenic to humans") based on the rat studies, but downgraded it to Group 3 ("not classifiable as to the carcinogenicity to humans") upon review of the subsequent research.

Saccharin has no food energy and no nutritional value. It is safe to consume for individuals with diabetes or prediabetes.

People with sulfonamide allergies can experience allergic reactions to saccharin, although it has been suggested that this may be due to a general predisposition to allergic reactions rather than a specific cross-reaction between antimicrobial sulfonamides and non-antimicrobial ones (like saccharin).

Saccharin was produced first in 1879, by Constantin Fahlberg, a chemist working on coal tar derivatives in Ira Remsen's laboratory at Johns Hopkins University. Fahlberg noticed a sweet taste on his hand one evening, and connected this with the compound benzoic sulfimide on which he had been working that day. Fahlberg and Remsen published articles on benzoic sulfimide in 1879 and 1880. In 1884, then working on his own in New York City, Fahlberg applied for patents in several countries, describing methods of producing this substance that he named saccharin. Two years later, he began production of the substance in a factory in a suburb of Magdeburg in Germany. Fahlberg would soon grow wealthy, while Remsen merely grew irritated, believing he deserved credit for substances produced in his laboratory. On the matter, Remsen commented, "Fahlberg is a scoundrel. It nauseates me to hear my name mentioned in the same breath with him."