Faerella Boczko, MS, CCC-SLP, BRS-S

Eating is an important part of our socialization. We use food as a way to sustain ourselves, to celebrate important events and even to mourn the loss of a loved one.

There are so many events in our lives that revolve around food. Imagine not being able to participate in these events because you have a hard time swallowing or could swallow at all.

Difficulty swallowing can impact a person psychologically and can be socially isolating.  As a normal person ages, swallow function can change, as it is a reflex that diminishes as a person ages.

In some cases, the changes are not noticeable, while those impacted by neurological or other diseases can have devastating effects.

Could it be possible that something as simple as changing the flavor of food improves one’s swallowing abilities? This article looks at the effect that chocolate has on the aging swallow. 

Millions in peril

It is estimated that by the year 2025, there are expected to be over 1 billion persons over the age of 60 years and most will have some sensory loss, including impairment in taste and smell perception. Studies have found that adding spices, MSG, and other flavorants increased liking of foods with older individuals.

Could chocolate do the same?

This study showed there was a small change and patients liked the chocolate taste. But we cannot definitively state at this time if chocolate has an effect on the aging swallow. We need to further explore the use of added chocolate to food to improve taste and swallowing ability in the older person

Chocolate for the gods

Chocolate was discovered over 2,000 years ago. The ancient Maya and Aztec people of Mexico and Central America are the first people known to discover the cacao tree. The use of chocolate in society has evolved over the millenniums from a form of currency to a sweet confection.

While the ancient Maya and Aztec people presented their gods with offerings of cacao seeds, modern medicine is now discovering the health benefits of this ancient product.

Doctors have discovered that plant polyphenols found in cocoa products (dark chocolate) have a positive effect on lowering hypertension. Specifically, the flavanols found in cocoa liquor have favorable effects on cardiovascular health.

Antioxidants, such as flavanols, are responsible for protecting the body╒s cells against the effects of free radicals. Free radicals are molecules produced when your body breaks down food, or by environmental exposures like tobacco smoke and radiation. Free radicals can damage cells, and may play a role in heart disease, cancer and other diseases. 

Tackling sensory challenges

The number of elderly individuals is increasing.  It is estimated that by 2025, most of the more than 1 billion people over the age of 60 will have some sensory loss, including impairment in taste and smell perception, and they will experience some developmental changes in oral-pharyngeal function.

Swallowing is a complex physiologic event composed of simultaneous and sequential contraction of muscles of the orofacial region, pharynx, larynx, and esophagus.

Changes that occur with the aging process, include vertebral column thinning, delayed oral stimulation, decreased swallow rates, a decrease in amplitude of lingual peristaltic wave, reduced lingual strength, reduced pharyngeal sensitivity, longer apnic time, and delayed UES relaxation relative to peak pharyngeal pressure.

Studies have found that there is a progressive decline in taste, smell and swallow functioning that begins as individuals age. Taste and smell losses occur in the aging and may influence the swallowing of food and affect nutritional intake in the elderly. 

Previous studies have found that the burn from hot pepper and the pungency of mustard are the result of stimulation of the trigeminal nerve. Adding a combination of MSG and flavorants increased liking of foods served in a cafeteria at a retirement center compared to unenhanced foods and flavor enhancement was more effective than flavor amplification.

The objective of this study was to determine if the addition of chocolate syrup added to a thin liquid (milk) improved timing of the initiation of swallows with an elderly population.

The chocolate milk method

Ten patients with a diagnosis of oral-pharyngeal dysphagia were enrolled in this small pilot study. Six males and four females, ranging in age from 71 years to 96 years participated. All participants underwent a fiberoptic endoscopic evaluation of swallowing (FEES) examination.

Following insertion of the endoscope, a Pentax FNL-10RP3 Fiber Naso Pharyngo Laryngo Scope, and observation of the pharynx, participants were given two trials of 10mL thin liquid (milk) without chocolate. Participants were provided with verbal instruction to “swallow.”

Two trials of 10mL thin liquid (milk) with chocolate syrup added were then provided to participants with verbal instruction to “swallow.”  Two Speech-Language Pathologists reviewed the FEES studies and measured the timing of the bolus flow/initiation of swallow from the moment of verbal instruction to “swallow.”

Objective timing measures of the bolus flow/initiation of the swallow from initial verbal instruction to “swallow” through to the completion of the swallow were obtained using the display timer on the FEES monitor. 

And the winner is …

The FEES examinations were analyzed immediately following completion of each study. The speech language pathologists reviewed the study with audio playback and use of digital timer on the monitor.

The study was paused at the moment the command “swallow” was heard on the audio playback and the digital displayed time was noted. The swallow was replayed in slow motion and paused at the completion of the swallow and the time was noted.

For this study, completion of the swallow was defined by visualization of the laryngeal vestibule after epiglottic inversion and return to neutral resting position.

Swallow initiation time was averaged across all participants in the study. The mean delay time of swallow initiation for participants without use of chocolate was 1.65 seconds. The mean delay time of swallow initiation with participants with use of chocolate syrup was 1.32 seconds.

The overall mean difference was 0.33 seconds, indicating a slightly positive but not significant change chocolate syrup.  

What it means

Results of this intervention showed minimal change in overall timeliness of initiation of swallow. The mean delay in normal aging adults is approximately 0.32 seconds for a 10mL liquid bolus.

Age and gender did not appear to be factors in improvement in timeliness of swallow function. Although there was a minimal change in swallow initiation time, overall swallow function did not appear to improve with use of chocolate syrup.

The use of flavor enhancement has been suggested to compensate for the diminished chemosensory function that is a contributing factor to impaired appetite and decreased intake and swallowing in the elderly.

SLPs need to explore the use of flavor enhancers with the elderly dysphagic population.  Limitations of this study include the overall small sample of the dysphagic population utilized, the difficulty visualizing chocolate on FEES studies, and the lack of inter-rater reliability.

Faerella Boczko, MS, CCC-SLP, BRS-S, is Chief, Department of Speech-Language and Swallowing Disorders, Jewish Home Lifecare in New York City; Siobhan McKeon (left), MS, CCC-SLP, is Assistant Director, Department of Speech-Language and Swallowing Disorders, at the facility.