- Consumption of propionate, a naturally occurring fatty acid that is used to help prevent food from molding, increases levels of hormones that are linked obesity and diabetes, a new study from the Harvard T.H. Chan School of Public Health showed.
- The study tested both mice and humans in a double-blind study. Results found those who consumed propionate had elevated levels of glucagon, norepinephrine and a newly discovered gluconeogenic hormone called fatty acid-binding protein 4 (FABP4) which contribute to insulin resistance and hyperinsulinemia – both hallmarks diabetes.
- Researchers indicated that although the U.S. Food and Drug Administration recognizes propionate as safe for consumption, these results warrant further investigation into the ingredient and its use in food.
Despite efforts to curtail diabetes in the world population, more than 400 million people suffer from the condition, the World Health Organization estimated. And according to the Harvard School of Public Health, the rate of diabetes is projected to increase 40% by 2040. This continued surge in obesity has led scientists and experts to believe that certain ingredients in today’s food, especially those involved in preparation or preservation, may be a contributing factor. Until now, there was very little evidence to support this hypothesis.
A new study from Harvard shows show a link between obesity, diabetes and the preservation ingredient. Propionate is a popular food additive that occurs naturally, but it also is added to many products like sports drinks, baked goods and bread to prevent mold and mildew from forming. Additionally, propionate discourages bacteria that occurs naturally from feeding and multiplying. This additive has been classified as safe to use by the FDA which does not limit the quantities that can be added.
Although the Harvard study ties propionate to obesity and diabetes, it is not the first study to call out this preservative for having adverse effects. Propionate has previously been affiliated with causing migraine headaches and inhibiting the stomach’s ability to heal inflammation. Research published in the Journal of Pediatrics and Child Health in 2012 found it could cause "irritability, restlessness, inattention and sleep disturbance in some children." Last year, McDonald’s removed calcium propionate from its buns.
As propionate is already a naturally occurring substance, scientists have started looking for another natural alternative to prevent molding that is not associated with adverse side effects. The challenge also is to find one that adheres to clean label demands from consumers.
The South African Journal of Science found there has been some success in employing natural antimicrobials such as acetic acid, lactic acid, a lactate-containing cocktail and calcium lactate. The study determined that “preservative regimes based on combinations of natural antimicrobials were successfully identified as potential replacements of calcium propionate.”
Particularly in light of consumer demand for clean label, it would be wise for companies to invest in identifying other naturally occurring preservatives that are not linked to one of the world’s greatest public health crises. Even if the state of public health isn’t enough motivation, consumer demand for easily comprehensible ingredients and minimal additives may force manufacturers to look elsewhere for food preservation techniques.
However, when it comes to removing additives and preservatives, there is a fine line that needs to be tread. According to two food safety and nutrition professors at Iowa State University, not all additions to food are bad. In fact, some significantly contribute to food safety. Professors Ruth MacDonald and Ruth Litchfield said that market demand appears to be driving the removal of food additives when there should instead be measured consideration of why they're there and the benefits of keeping them. Calcium propionate was specifically called out as an additive worth considering.