Many manufacturers of dietary products use a variety of sweeteners — substances that have a sweet taste and can thus replace the usual sugar. Sweeteners can be of natural or artificial origin. One of the latter is aspartame.
First encounter and history of creation
Aspartame is the methyl ester of a dipeptide, that is, a substance consisting of two amino acids — L-aspartic acid and L-phenylalanine. Its chemical formula is C14H18N2O5.
Aspartame was first synthesized in 1965 by James M. Schlatter. He worked for the American pharmaceutical company G.D. Searle and tried to synthesize a hormone called «gastrin,» or rather its active part consisting of only five amino acids. This hormone is a natural product of gastric secretion and is also used in a number of diagnostic procedures for GI diseases. A drop of the intermediate synthesis product fell on his finger, he licked it trying to turn the page—and was struck by the sweetness of the taste. Further research showed that the substance was about 200 times sweeter than sugar, did not have the bitter taste that many sugar substitutes have, but had a long, sweet aftertaste. In 1970 Schlatter received a patent for his invention, and in 1974 the FDA (Food and Drug Administration, USA) approved the use of aspartame in food industry. This was largely due to the work of Norwegian researcher Torunn Atteraas Garin.
Where is it used?
Currently, aspartame is the second most popular (after fructose) industrial sweetener and, accordingly, the field of its application is very wide. The only limitation is its thermolability (it is destroyed by prolonged heating) The greatest distribution of aspartame was in the food industry, but it can also be found as part of a variety of pharmaceuticals as a filler. It also has applications in households (cold soups and drinks, salads, etc.). It is often used by diabetics and those who wish to limit the calories in their diet, since the energy value of aspartame is 4 kcal/g (which is the same as the caloric value of sucrose), but it needs 200 times less.
Harm or benefit?
The debate about the harm of aspartame to the body has been going on for half a century, now fading, now flaring up again. The main reason for them is the fact that when aspartame is metabolized in the body, it releases methanol, a well-known neuro- and hepatotoxic poison.
The FDA has repeatedly suspended (or restricted) its approval of aspartame and renewed it as many times. Final approval was granted in 1996. Nevertheless, in 1998 a widespread e-mail hoax appeared that declared aspartame guilty of causing multiple sclerosis, systemic lupus erythematosus, blindness, seizures, headaches, depression, anxiety, memory loss, birth defects and other mishaps up to and including premature death. Special studies conducted in 1999 refuted these claims.
The next major attempt to undermine the credibility of aspartame relates to the publication in April 2008 of a paper by South African scientists in which they spoke of the ability of aspartame metabolites to alter brain chemistry and damage nerve cells. However, the commission of experts of the European Food Safety Agency noted that this work had serious scientific errors, and the conclusions were partly based on sources from the Internet, which is unacceptable to science.
The discussion is now closed with an article published by the European Food Safety Authority (EFSA) in 2015, «Scientific Opinion on the Reassessment of Aspartame (E 951) as a Food Additive.» It noted that:
- Only metabolites, not aspartame itself, are detected in the blood;
- Its acute toxic effects (as well as its genotoxic effects) have not been scientifically proven;
- there is no epidemiological evidence of a link between aspartame consumption and the incidence of cancer;
- Obviously, this statement is close to the truth. To prove it, let’s understand the metabolism of aspartame. In the human digestive tract, it quickly breaks down into phenylalanine, asparagic acid and methanol in a ratio of 5:4:1. The biological effects of these substances are well known.
What does aspartame break down into and how do the breakdown products affect our bodies?
An essential amino acid that has the following properties:
- stimulates brain activity, relieves insomnia and depression;
- Reduces appetite and prevents fat deposition;
- regulates the functions of the endocrine glands and affects the synthesis of brain mediators;
- stimulates the growth of muscle mass and the production of melatonin;
- Performs a variety of other functions.
Excessive phenylalanine may cause headaches, nausea, heartburn, CNS dysfunction, and allergic reactions.
2. Aspartic acid
A substitutable amino acid that participates in the synthesis of urea and myelin and in energy, carbohydrate, nucleotide and amino acid metabolism. Its deficiency is manifested by headaches, insomnia, irritability and aggression.
Primarily affects vision (often irreversibly). Also has hepato- and nephrotoxic effects, affects the functioning of the cardiovascular system.
Obviously, the metabolic products of aspartame can have significant biological effects. However, simple calculations show that in the case of aspartame, all concerns are unnecessary.
Amino acids are the same regardless of their source. Therefore, we can only talk about the toxic effects of methanol. From 1 liter, a drink containing 600 mg of aspartame, about 60 mg of this alcohol will be released. At the same time, fruit juices can contain up to 160 mg/L of the substance. And the human body itself produces 0.4-1.4 g (!) per day.
A safe standard of aspartame is considered to be 40 mg/kg of weight (in the U.S. 50). It is easy to calculate how much and what one should consume to exceed this figure.
Thus, a strict ban on the use of aspartame is set only for patients with phenylketonuria.
In what products can I find it?
This substance may be included in:
- confectionery products;
- Chewing gum;
- Candy bars;
- creams and curds;
- fruit desserts;
- vitamin complexes;
- cough lozenges;
- ice cream;
- soft drinks;
- hot chocolate.
How do I find the contents of a product?
Manufacturers are required to indicate the composition of the product on the label. Aspartame has a number of synonyms: Sladex, Nutrasvit, Aspamix. According to the classification of food additives in the European Union, it has the index E951.
The popular synthetic sweetener aspartame can be found in many products, not necessarily food products. It has a number of extremely useful properties, while its harm has not been scientifically proven. The use of aspartame is forbidden only to a small part of the population — those with phenylketonuria, a rare genetic disease.