Emulsifiers/Metabolic syndrome [FB], Mouthwash, Toothpaste, Oral hygiene, Additives, Titanium dioxide/nanoparticles

Optimizing Metabolism

When the Solution Is the Problem: Do Your Mouthwash and Toothpaste Have Untoward Metabolic Effects?

By Ingrid Kohlstadt, MD, MPH

Overview

My April 2018 Townsend Letter column is entitled “Crossing the Medical Dental Divide.” Readers commented their surprise at the many areas where dentistry can improve medical outcomes. There’s more. This column identifies four categories of additives commonly found in oral hygiene products. The additives do not stay in the mouth and have been shown to cause untoward metabolic effects. Reducing exposure to offending additives can improve overall health.

Emulsifiers

Emulsifiers provide an important food technology. They enable oil and water to mix. Mouthwash that is clumpy or has an oily film wouldn’t stay on the market for long. Emulsifiers expand the options. They can provide smooth, alcohol-free, no-stir mouthwash. But there’s a downside.

Emulsifiers continue to enable oil and water to mix even after the mouthwash has been used. Cell membranes are biologic structures that limit permeability by separating oil and water. A solution with emulsifiers is absorbed even if it isn’t swallowed. During digestion the rate and manner in which oil and water mix is carefully calibrated. Increasing the permeability of the intestinal lining is associated with symptoms sometimes referred to as leaky gut.

The food industry’s use of emulsifiers was challenged in March 2015 when Nature published the murine research of scientists Andrew Gewirtz and Benoit Chassaing from Georgia State University.¹ Mice exposed to the emulsifying agents developed metabolic syndrome faster than those unexposed. Differences were detected at levels one-tenth that permitted by the FDA. The authors and other scientists have since conducted human studies with the same finding.² Evidence mounted when removing exposure to emulsifiers demonstrated health benefit. A recent randomized study demonstrated that prescribing a no-carrageenan diet can extend remission of inflammatory bowel disease.²

Emulsifiers have an absence of evidence but not evidence of absence. In August 2017, more than two years after the Nature study that raised a safety concern, another investigation of emulsifiers was published “[b]ecause no published dietary exposure estimates for commonly used emulsifiers exist for the U.S. population.”³

Avoiding select emulsifiers may be adequate. While all emulsifiers act to enhance permeability, those that exist naturally in the diet don’t raise as much concern as others. For example, lecithin is an emulsifier found in food naturally and is considered a safer additive than carrageenan and carboxymethyl cellulose. While carrageenan is “natural” because it is extracted from red seaweed, it is not a customary component of food and is not “natural” to the human diet. Carboxymethyl cellulose is also “natural” because it’s derived from cellulose, which is made water soluble through chemical reactions; but cellulose it not naturally digestible by humans. Synthetically–derived emulsifiers include polysorbates, currently used in medicines and vaccines with rising debate. I share the sentiments of Dr. George Lundberg voiced in his Medscape editorial.⁴

Food Colorings and Preservatives

Mouthwash has to sit on the bathroom shelf unrefrigerated. Artificial food coloring is less likely to fade over time than natural colors. Sitting on the bathroom shelf also requires adding preservatives.

Food colorings are among the chemical additives with known effects on the central nervous system.⁵ Consumption of the food colorings sunset yellow FCF, quinoline yellow, carmoisine, allura red, tartrazine, and ponceau aggravates attention deficit hyperactivity disorder (ADHD). The preservative sodium benzoate has similar effects. Conversely, removing the additives from diet ameliorates ADHD symptoms. The science has compelled Europe to take regulatory action.⁵

Here is where I have observed tragic irony. What do you find in the restroom of a dentist’s office? Mouthwash. What are you supposed to do at a dental visit? Sit still. No one has published this data, but if it were available I anticipate it would point to an inconvenient truth. Some children prescribed medications to treat ADHD may have been able to avoid the need for medical management or increased dosing if they hadn’t been given provocateurs of their symptoms at the dentist’s office.

Sweeteners – New Findings

High-intensity non-caloric artificial sweeteners (NAS) are useful technology for oral hygiene products, since they are a substitute for sugar which is known to be harmful for the teeth. It’s also been known that NAS alters satiety and can increase the development of diabetes. Late-breaking research has discovered the mechanism by which NAS alter satiety signaling.⁶

A first in human study conducted by Dr. Richard Young of Adelaide Australia’s School of Medicine elucidated a mechanism. In the presence of artificial sweeteners, less glucose may reach the distal portions of the intestine that release glucagon-like peptide 1 (GLP-1). GLP-1 is an incretin hormone that is protective against the metabolic syndrome.

Nanoparticles

Titanium dioxide whitens various foods, adds texture to yogurt and cosmetics, serves as a mild abrasive and whitener in toothpaste, inhibits growth of food pathogens, and blocks light especially in the UVB spectrum.

Food-grade titanium dioxide is larger than nanoparticles, but research is now showing that the titanium dioxide used in foods, cosmetics, sunscreens, and oral hygiene products does contain nanoparticles. Food additive titanium dioxide (E171) is micronized, yet a fraction of this is nanoparticles.⁷ This is alarming information because nanoparticles are metabolic wildcards, traveling through cells unchaperoned and interacting with the immune system in unstudied ways. For example, sunscreens using nanoparticles of titanium oxide have been shown to be associated with lung cancer when they are applied by spraying. This is because the nanoparticles penetrate deeper into lung tissue than was realized.⁸

Could titanium-containing nanoparticles found in food and cosmetics be contributing to hypersensitivity reactions to titanium alloy dental and orthopedic implants? The answer is unknown, although possible. Avoiding nanoparticle-sized titanium where possible may reduce metal sensitivity and preserve titanium as an implant material for both dental and medical uses.

Conclusion

Food technologies with metabolic effects are pervasive. They are not limited to processed foods as sometimes assumed. Health foods, dietary supplements, good-for-you foods, and oral hygiene products incorporate newer food technologies. Dentists and physicians can work together to protect patients against mouthwash solutions with metabolic problems.

References

1. Chassaing BKO, et al. Dietary emulsifiers impact the mouse gut microbiota promoting colitis and metabolic syndrome. Nature. 2015;519(7541):92-6.

2. Bhattacharyy S, et al. A randomized trial of the effects of the no-carrageenan diet on ulcerative colitis disease activity. Nutr Healthy Aging. 2017;4(2):181-92.

3. Shah R, et al. Dietary exposures for the safety assessment of seven emulsifiers commonly added to foods in the United States and implications for safety. Food Addit Contam Part A. 2017;

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(6):905-17.

4. Lundberg G. Demonizing processed food: It’s the additives. Medscape Internal Medicine. 2017:https://www.medscape.com/viewarticle/884444

5. Food colours and hyperactivity. Food Standards Agency 2012; https://www.food.gov.uk/science/additives/foodcolours

6. Young R. Artificial sweeteners alter gut response to glucose (Abstract). European Association for the Study of Diabetes (EASD) 2017 Annual Meeting Lisbon, Portugal: Medscape Medical News, 2017.

7. RVIM. Health effects due to titanium nanoparticles in food and toothpaste cannot be excluded. Government of Netherlands. 2016.

8. Smijs TG, Pavel S. Titanium dioxide and zinc oxide nanoparticles in sunscreens: focus on their safety and effectiveness. Nanotechnol Sci Appl. 2011;4(95-112.)