We are always advised to eat a healthy diet rich in fruits and vegetables, whole grains and lean meats and to avoid processed foods containing high levels of preservatives. However, it is likely that most of us have never questioned why preservative-laden foods are harmful for our overall health.

Preservatives linked to gut disease and obesity:

A study led by Andrew Gewirtz at the Georgia State University and published in the March 5th issue of the Nature, has uncovered some of the reasons behind the harmful effects of preservative consumption. In particular, the scientists were interested in determining the effects of two well-known preservatives, carboxymethylcellulose (CMC) and polysorbate-80 (P-80) in mice.

• CMC is listed as E466 in food ingredients. Other names include cellulose gum and sodium salt.  CMC works as a thickener, stabilizer and binder in various foods such as ice cream, salad dressings, and spreadable cheeses.
• P-80 is also known as tween 80. It is used as an emulsifier and defoaming agent. Foods that may contain p-80 include ice cream, pudding and sauces.

The researchers conducted initial experiments in which they added preservatives to the mice food. The results showed that CMC and P-80 decrease the thickness of the mucosal lining of the intestine that functions as a barrier between the microbes residing in the gut and the intestinal cells. A reduction in the mucosal lining caused the gut bacteria to become invasive. Furthermore, the dietary consumption of these preservatives also led to colitis, an inflammatory condition of the colon.

Perhaps one of the most important scientific finding that results from this study is the disruption of the levels of the microorganisms residing in the gut. Such preservative-induced fluctuations in the number of gut microorganisms led to an increase in weight (and fat).

The takeaway:

The present study represents an important advance in sharpening our understanding on the harmful effects of emulsifier consumption. It is likely that similar changes take place in humans upon consuming foods with high levels of preservatives. The increase towards a more preservative-based consumption culture can (partially) help explain the rise in obesity over the past several decades. It remains to be determined and therefore be of interest to investigate which other common preservatives have harmful effects.

Are you still using CMC or P-80 in your food products and looking for a clean-label alternative? Feel free to reach out to Rachel Murkett, PreScouter Project Architect and food and beverage industry thought leader.