Here at INQUIS, we often conduct trials that examine satiety and feelings of fullness. Consumers are looking for foods that promote fullness and help them manage their food intake and the food industry is developing products that can meet those demands.

Such trials, however, can be complicated. When measuring feelings of fullness or assessing food intake, it can be challenging to demonstrate significance and careful thought needs to be given to the study design.

Here are some important aspects to consider when designing a satiety trial that can demonstrate a statistically significant difference:

Power calculations

In order to focus on satiety, the trial needs a large enough sample size that filters out the noise and variability in the system to focus on feelings of fullness. Having a power calculation that is appropriate for the food product is crucial for the protocol design.

Subject pool

Consider the population you will be marketing your product to and have the research participants reflect this. This may mean assessing and excluding restrained eaters.

Difference between test meals

The dose of the test ingredient should be large enough to detect significance. A dose response curve may be helpful to determine the dosage required for an effect. The energy content of the test and control products should be matched for a valid comparison.

Including a negative control (0 energy) and/or a positive control (a larger portion of one or both of the products) may be more costly, but may be helpful to assess the validity of the measurements and study outcomes.

Feelings of fullness vs. ad lib meals

This is where the ultimate objective is an important consideration. Food intake may be more appropriate if assisting with weight loss is the ultimate goal. Other products have a stronger focus on making consumers feel better or feel less hungry, so subjective measures may be more appropriate. Many times, we measure both in the same trial.

Know your product and time it right

It’s always preferred to have a study design mimic the way in which you intend for your product to be used. For example, if it’s intended to be used as a meal replacement, if should be served to research participants instead of a meal. It’s also helpful to have an estimate of the anticipated timing of significant effect, so that this can be taken into consideration when designing the endpoints for a trial. Sometimes, we conduct a pilot study to determine the best timing for a meal in a research study.

“Trials that examine food intake and satiety can be challenging, but also extremely rewarding when they are designed and executed correctly, providing the evidence required to move forward, “ says Dr. Alexandra Jenkins, Senior Scientist at INQUIS.