The safety of purified steviol glycosides has been evaluated through rigorous scientific
research, which supports the safety of purified stevia leaf extracts for use as a sweetener.
The safety of purified stevia leaf extract is supported by:
• Stevia historical use dating back centuries in South American countries and for over four decades in Japan; • Years of rigorous scientific research on purified steviol glycosides, the sweet components of the stevia leaf; and
• The positive scientific statements of several food safety and regulatory authorities, including JECFA and the European Food Safety Authority (EFSA) which support the safety of purified stevia leaf extract for use in foods and beverages.
ingredient safety assessment
The safety assessment for food ingredients by regulatory agencies is an extensively
detailed and lengthy process, designed to ensure that a new food ingredient, such as a
non-caloric sweetener, does not pose a risk for any consumers, including children and
The protocols that must be used for safety studies have been established over many
years, by independent international experts, and are globally accepted. The results from
toxicology or safety studies are used to establish the Acceptable Daily Intake (ADI). The
ADI is defined as the amount of a food ingredient that people can consume on a daily
basis during their lifetime without any appreciable risk to health. The ADI is established
from long-term animal studies, in which animals are fed diets containing increasing
levels of the food ingredient for the majority of their lifetime, through stages of development and growth. Detailed assessment of the animals’ health is completed, and the highest dose that resulted in no adverse effects is called the no observable adverse effect level (NOAEL). To adjust for any possible individual differences (intra-species) or differences between the test species and humans (inter-species), the NOAEL level is
divided by 100 (10X for intra-species and 10X for inter-species). This is called a safety
factor, and is designed to provide even more assurance that the ADI level will be safe
for all consumers.
Animal studies are critical to the safety assessment, as it is not ethical to test a new
ingredient in humans without determining the level that is safe. Animals can be given
very high doses, which are used to increase the likelihood of detecting any adverse effect the ingredient may cause, and to be able to determine how the body uses the ingredient. Lower doses are used to determine the amounts that can be consumed every day with no adverse effect. Once animal studies determine the amount that is safe, additional studies are done in humans to confirm the validity of the animal studies.
The next step in the approval process is to estimate the likely consumption of the food
ingredient, by different segments of the population. This includes different age groups
and sexes. The consumption estimates are based on consumer surveys on consumption
of the foods and beverages that will contain the ingredient. These data are used to set
limits on the levels of the ingredient allowed in each type of food and beverage, to ensure that no consumer will be exposed to more than the Acceptable Daily Intake in their diet.
The ADI is a conservative safe exposure level and does not represent a maximum
allowable daily intake level and should not be regarded as a specific point at which safety ends and possible health concerns begin. Because the ADI has a built-in safety margin and is based on a chronic lifetime exposure, occasional consumption in amounts greater than the ADI would not cause adverse effects or concern.
After approval, regulatory agencies continue to monitor scientific literature for new
studies or reports of adverse effects of ingredients, and will carefully review the results to
ensure on-going safety of the use of the new ingredient.