RecruitingNAINTERVENTIONAL

Evaluation of Food Additive Contributions to Obesity: Pilot Study 1

This study, called "Evaluation of Food Additive Contributions to Obesity: Pilot Study 1," aims to explore the potential link between specific food additives and body weight in humans. While we know very little about this topic, this initial research focuses on a common additive called potassium sorbate. The main goal is to see if it's practical to measure how much food people eat after they've had either potassium sorbate or a dummy pill (placebo). Participants will temporarily reduce other food additives in their diet before taking part. This is a small, early-stage study to help plan bigger studies in the future, if this one shows it's a good idea.

At a glance

Status

Recruiting

Phase

Sponsor

McMaster University

Enrolment target

Start

10 Feb 2026

Estimated completion

01 Jun 2026

Obesity (Disorder)

What is this study about?

This study is looking into something important: whether common ingredients added to our food, like certain preservatives, might have an impact on our body weight. It's often hard to know what effects these additives have on humans, but this research aims to take a first step in finding out more. The specific additive being tested in this study is called potassium sorbate, which is commonly used to stop mould and yeast growing in foods.

This is a "pilot study," which means it's a small, initial trial. Its main purpose isn't to give a final answer on whether potassium sorbate causes weight gain or loss, but rather to see if it's even possible to properly measure people's food intake after they've had this additive. If we can reliably measure these things, it will help researchers design much larger and more detailed studies in the future.

Participants will be given either potassium sorbate or a dummy pill (placebo) on different occasions, with a break in between. Before taking part, they will also be asked to temporarily reduce the amount of other similar food additives in their diet. This careful approach helps the researchers focus on the specific effects of potassium sorbate.

Key takeaways

Exploring if a common food additive affects body weight.
This is a small, early-stage study (pilot study).
Compares potassium sorbate to a dummy pill (placebo).
Measures food intake over 24 hours.
Focuses on adults who are overweight (BMI 30-39.9).
Aims to help plan future, larger studies.

Who may be eligible?

To join this study, you need to be an adult between 20 and 80 years old and have a Body Mass Index (BMI) between 30 and 39.9. You also need to be willing and able to follow all the study instructions and procedures.

There are several reasons why someone might not be able to join. For example, if you've lost a lot of weight recently (3% or more in the last three months), or if you've had or are planning to have weight-loss surgery soon, you wouldn't be eligible. The study also can't include people who are currently on weight-loss programmes or taking certain weight-loss medications, or those who use steroids regularly.

Other reasons for not being able to take part include having very high alcohol consumption, certain untreated mental health conditions like bipolar disorder or ADHD, or an eating disorder. If you are pregnant, planning to become pregnant, breastfeeding, or planning to become a father in the next six months, you also can't join. People with certain types of diabetes (Type 1, uncontrolled Type 2, or Type 2 needing insulin) are also not suitable for this particular study, nor are those who dislike the foods that will be served during testing.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you between 20 and 80 years old?
Is your BMI (Body Mass Index) between 30 and 39.9?
Have you *not* lost 3% or more of your body weight in the last 3 months?
Are you *not* pregnant, breastfeeding, or planning a pregnancy/fatherhood in the next 6 months?
Do you *not* have Type 1 diabetes or uncontrolled Type 2 diabetes?
Are you willing to temporarily adjust your diet to reduce certain additives?

Answer every question to see your result.

What does participation involve?

If you take part in this study, you will be given either potassium sorbate or a placebo (a dummy pill with no active ingredient) on two separate occasions, with a "washout period" in between. This means you'll have a break where no study medication is taken, to make sure the first dose is completely out of your system before you receive the second. The order of receiving the active substance and the placebo will be random.

Before taking part, you will be asked to temporarily reduce your intake of other similar food additives in your normal diet. During each testing session, researchers will measure how much food you eat over 24 hours. You will need to attend specific visits for the administration of the pills and for food measurements. The total duration of your participation in the study, including the washout period, will be relatively short, likely over a few weeks.

Potential risks and benefits

Taking part in research studies always has potential benefits and risks. A potential benefit of this study is helping researchers understand more about how common food additives might affect body weight, which could lead to better health advice in the future. As this is an early-stage study, there's no guarantee of direct personal health benefits. Potential risks related to potassium sorbate are generally considered low at the doses used in food, but like any substance, some people might experience mild digestive upset or allergic reactions. All potential risks will be fully explained. Remember, your participation is voluntary, and you have the right to withdraw from the study at any time, for any reason, without it affecting your medical care.

Locations (1)

McMaster University Medical Centre
Verified postcode
Hamilton, Canada· Recruiting

Common questions

What is potassium sorbate?

It's a common chemical additive used in many foods and drinks to prevent mould and yeast from growing, helping them last longer.

What does 'pilot study' mean?

A pilot study is a small, initial study done to see if a larger, more detailed study is possible and practical to carry out in the future.

What is a 'placebo'?

A placebo is a dummy pill or treatment that looks exactly like the real one but contains no active ingredients. It's used to compare against the real treatment.

Will this study help me lose weight?

This study isn't designed as a weight-loss programme. Its main aim is to gather information for future research, not to provide direct personal health benefits like weight loss.

How long will I need to be involved?

The total time you'd be involved in the study, including the breaks between treatments, would likely be for a few weeks.

How to find out more

Natalia McInnes, MD, MSc

natalia.mcinnes@mcmaster.ca 19055212100 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.