Sweeteners

Sweeteners are synthetically (artificially) produced or of natural origin and are used as an alternative to sugar in foods. Together with sugar substitutes, they form the functional class “sweeteners” of food additives approved in the European Union. Sweeteners are labeled as “sweeteners” in the list of ingredients and are also shown with the E-number or the name of the specific substance. Compared to conventional household sugar (sucrose) or sugar substitutes, sweeteners have a much higher sweetening power and a negligible calorific value. Sweeteners do not have a cariogenic effect and do not raise blood glucose levels, which is why they are particularly recommended in the context of diabetes mellitus. Sweeteners approved in the EU include:

Sweetener E number x times the sweetening power of sucrose (“household sugar”)
Acesulfame-K 950 130- to 200-fold
Advantam 969 20,000- to 37,000-fold
Aspartame 951 200-fold
Cyclamate 952 30 to 50 times
Neotame 961 7,000- to 13,000-fold
Saccharin 954 300- to 500-fold
Stevioglycosides/stevioside 960 300-fold
Sucralose 955 600-fold
Thaumatin 957 2,000- to 3,000-fold
Neohesperidin DC 959 400 to 600x
Aspartame-acesulfame salt 962 350-fold

Because of their high sweetening power, sweeteners are added to foods only in small amounts. The most common sweetener, aspartame, contains the two amino acids aspartic acid and phenylalanine. People suffering from the disease phenylketonuria (PKU) must therefore avoid the sweeteners aspartame and aspartame-acesulfame salt. Corresponding products are labeled with the warning “contains a source of phenylalanine” or “with phenylalanine.” Phenylketonuria is a congenital metabolic disorder by which the amino acid phenylalanine cannot be broken down, consequently accumulating in the body and leading to severe mental developmental disorder if left untreated.

Effects of sweetener consumption on blood glucose levels and diabetes risk

Sweeteners are used for weight loss, especially in beverages, because of their negligible caloric value. They maintain the sweet taste of sugar-free and energy-reduced foods. Furthermore, they do not cause blood glucose levels (blood sugar levels) to rise.Recent findings, however, suggest that these relationships should be viewed critically:

In one study, mice were given commonly used sweeteners (saccharin, aspartame, sucralose) in their drinking water. After a short time, the blood glucose values (blood sugar levels) in the oral glucose tolerance test (sugar load test, also known as oGTT for short) increased significantly. These findings are supported by another study in which subjects using sweeteners gained weight, had elevated fasting glucose levels and HbA1c levels (long-term blood glucose levels). The oral glucose tolerance test was also pathological (abnormal).The researchers suspect that sweeteners promote the growth of gut bacteria that increase the absorption (uptake) of glucose from the gut. Increased body weight and long-term elevated blood glucose levels are considered key risk factors for diabetes (diabetes mellitus, type 2). Until now, there has only been speculation about the exact mechanism by which artificially sweetened beverages promote the development of diabetes. Now, at the European Diabetes Congress (EASD Congress) in Lisbon (2017), researchers presented for the first time a mechanism in humans showing how synthetic sweeteners can adversely affect the postprandial (after-meal) glycemic response. In the study, participants were given the sweeteners sucralose (E 955; 600 times sweeter than sucrose/household sugar) and acesulfame K (E 950; 200 times sweeter than sucrose) for two weeks. The dosage corresponded to a consumption of approximately 1.2-1.5 liters of a diet beverage per day. The sweetener-consuming subjects absorbed about 20% more glucose in the intestine than the placebo group and had higher plasma glucose levels (by 24%).In addition, the GLP1 response to sugar intake was lower (by 34%). GLP1 (glucagon-like peptide-1) is one of the incretins (endogenous intestinal hormones) and is produced and released in response to glucose in the chyme (food pulp). The peptide hormone is primarily involved in the control of glucose metabolism. By enhancing the release of insulin (stimulation of pancreatic beta cells), it contributes to lowering blood glucose levels. Sweetener-induced increased glucose absorption results in less glucose reaching the mid and distal (more distant) portions of the intestine. As a result, less GLP1 is secreted. Note: In the studies, participants drank very large amounts of the sweetener-added beverage. It remains unclear whether these effects also occur with moderate (moderate) consumption of sweeteners. Data are also still lacking regarding long-term effects.

Effect of sweeteners on appetite

The suspicion that sweeteners stimulate appetite and increase caloric intake has not been confirmed in recent years. Although one study showed that participants’ appetites increased shortly after consuming a sweetener-infused beverage, this urge quickly subsided and did not lead to increased caloric intake. In fact, the opposite effect occurred when larger amounts of the diet drink were consumed. Consequently, it can be said that sweeteners do not cause hunger.

Influence of sweetener consumption on weight development

The question of whether sweeteners lead to weight gain in the long term was addressed by a meta-analysis of 15 randomized controlled trials (RCTs) and 9 prospective cohort studies involving more than 100,000 participants: Fat mass and BMI were significantly lower in participants who regularly consumed sweeteners. In addition, the subjects were better able to maintain the weight they achieved. Currently, there is no evidence that sweeteners are adipogenic (promote weight gain).

Carcinogenic potential of sweeteners

Sweeteners repeatedly enter the debate because of their possible carcinogenic (cancer-causing) effects. Animal studies showed that the sweetener aspartame can trigger brain, lymph gland and ureter cancer. However, there are also studies with contrary results. Furthermore, saccharin, ingested in high doses, led to bladder cancer in animal studies. The extent to which these results can be transferred to humans has not been established. The sweetener cyclamate causes damage to testes and sperm in animal studies. The results are only considered to be transferable to humans to a limited extent, since the effects only occurred at very high doses. Against this background, a very low ADI (Acceptable Daily Intake)* was set for cyclamate as a precautionary measure. Cyclamate can be converted in some people to cyclohexylamine, which increases blood pressure, and can therefore have an adverse effect on people with cardiovascular disease. Cyclamate is not approved in the United States. It was only in 2011 that the European Food Safety Authority (EFSA) re-evaluated aspartame and classified it as safe. The German Federal Institute for Risk Assessment (BfR) also considers the sweeteners approved in the EU to be harmless at present, as long as the specified maximum amounts are observed. The ADI (acceptable daily intake) for aspartame is 40 mg/kg body weight, for saccharin 2.5 mg/kg body weight and for cyclamate 7 mg/kg body weight. In conclusion, it can be said that a conscious use of sweeteners as well as a moderate consumption may be appropriate if there is a corresponding indication (e.g. diabetes mellitus). National and European authorities as well as professional societies classify sweeteners as safe. * The ADI is the amount of a particular substance that a person can consume every day for the rest of his or her life without causing damage to health. In other words, it is used for the toxicological evaluation of a substance.The ADI value is given in milligrams per kilogram of body weight. Example: If the ADI for an additive is 0.1 mg/kg, this means that a 70 kg adult can consume 7 mg (70 kg x 0.1 mg) of this additive every day, and a 40 kg child 4 mg, without fear of damage to health.