AUTHOR: Shirley Gutkowski, RDH, BSDH
AUDIENCE: Dentists; Dental Hygienists; Dental Assistants; Specialists; Office Staff
ABSTRACT: Functional foods can be communication tools for all health care providers, especially in dentistry, where the mantra has been so monotonous – brush, floss, avoid sugar – that people don’t hear it any longer. This course focuses on the role functional foods play in our overall oral health. From chewing gum to tea, properties in certain foods can serve as a way to protect teeth, gums and overall systemic health.
- Define functional foods and describe the benefits they can have on oral health.
- Recognize the properties in functional foods that contribute to oral and systemic health.
- Relay that functional foods can be used as communication tools for health care providers, especially in dentistry, to enhance patient engagement.
CLINICAL CATEGORY: Functional Foods
CE ACTIVITY: Self-Instructional
NUMBER OF CREDITS: 2 CE Credits
PUBLISH DATE: April 2014
EXPIRATION DATE: April 2017
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Embracing functional foods can lead to better oral health care, patient engagement
What is a functional food? One could argue that all foods are functional. Food functions as fuel for the bodies of all sentient beings. The term “functional food” refers to an isolated group of food that has added benefits, or healthful benefits. Functional food provides an additional function related to promoting health or preventing disease.
Functional foods may be whole and fresh or processed, coming wholly from a kitchen or lab. Foods, such as berries, function on a cellular level, while others, such as chewing gum, function on a physical level. Mostly, functional foods span categories and features. Functional foods should not be confused with fortified foods such as white bread, in which all of the nutrients are removed as a beginning step and fortified to government standards as an end-step. Knowing how to recommend functional foods is important to health care providers, but there is no near end to what we’re learning about functional foods.
Chewing gum is probably the least-mentioned functional food. In dentistry chewing gum is persistently trying to gain credibility. As a delivery device for anticariogenic ingredients, chewing gum has made some inroads, which is just the tip of the iceberg in terms of the benefits attributable to this functional food. Non-nutritive chewing has been studied for a multitude of indications: brain function,1, 2 post-operative bowel movements3 and dental effects.4 The dental benefits include increased salivary flow, decreased sugar clearance times, and increased facial muscle tone. Chewing gum can also contain a variety of additives that promote dental health, such as polyol sugars, chlorhexidine and fluoride.
Gum ingredients have become the dental story. Xylitol has captured dentistry for the last decade by acting on both mechanical and medicinal aspects of health promotion. Applications of xylitol in any other way continue to be inferior to the delivery of this sugar alcohol to the oral biofilm.
The addition of intense sweeteners to the gum to replace traditional and known cariogenic sweeteners increases the flavor longevity. The longer the flavor lasts, the longer the chewing goes on. Long-term chewing is why this activity still remains black-listed for dentistry. Lengthy non-nutritive chewing sessions may contribute to temporal joint disorders.
Managing expectations of chewing gum recommendations should include a discussion on how long to chew the gum. The recommended amount of time for chewing xylitol, for instance, is five minutes. And using xylitol chewing gum is equal in cost and results as sealants are, offering a new way to manage an old infection.4
Other ingredients have been added to make chewing gum more dentally healthful. In Europe and Asia, fluoride is added to over-the-counter chewing gums. Along with xylitol, other polyols are added so the gum may be categorized as non-cariogenic. Bicarbonate, chlorhexidine and essential oils from tree bark5 are also added to improve oral health by impacting the oral biofilm.
Nicotine, nystatin, caffeine and aspirin are just some of the medicines delivered by way of chewing gum. Chewing gum must be included6 in the list of functional foods. Dental chewing gums are so important worldwide that Toothfriendly International was formed to help people identify those chewing gums that are tooth-friendly.
Probiotics are a characteristic of many fermented foods, such as miso soup, sauerkraut, soft cheeses, sour dough, kefir, tempeh and sour pickles. Yogurt is arguably the most popular functional fermented food known for probiotics to support gut health. Live cultures in yogurt repopulate the gut with healthful bacteria important in gut and systemic health.
The term prebiotics is also creeping into the lexicon. Prebiotics are not bacteria, as probiotics are. Prebiotics are small, indigestible or partially digested food molecules that feed the resident colon biota. For instance, xylitol is not metabolized by oral bacteria; however, it feeds the beneficial bacteria in the gut. While yogurt has active cultures for the intestinal flora, the probiotics in yogurt do not contribute health benefits to the mouth. Gut flora is how anthocyanins (flavonoids) break down and travel through the gut wall into the system to provide health benefits.
As a milk product, the calcium and phosphorous in the milk has some direct topical health for enamel. The ingested calcium contributes to overall function of the body, making it a great food on its own. Adding sugar and fruit alters the benefits quite a bit. Eating plain yogurt with a teaspoon of xylitol over fresh or frozen fruit is a much better option, as that recipe increases the functional aspect of the fruit and the yogurt. Adding blueberries, a fruit very high in anthocyanins and proanthocyanidins, to plain yogurt converts the yogurt dish into a superfood.
Berries are considered functional foods because of their high levels of anthocyanins, also known as flavonoids. These are the key health and nutritional features of all fruits and vegetables. Anthocyanins are associated most with deep colors, such as the red of a ripe cranberry, the purple of a grape and the black of a cherry. Anthocyanins are powerful antioxidants.
Oxidants develop from body processes such as normal aerobic respiration, metabolism and inflammation. Environmental free radicals form from positive and negative environmental factors, including pollution, sunlight, strenuous exercise, X-rays, smoking and alcohol. Simple aging decreases the function of the body’s antioxidant systems, causing cell parts damaged by oxidation to accumulate7 and making supplementation necessary. Antioxidants, such as foods high in anthocyanins neutralize free radicals either by providing an electron needed to make the pair or by breaking down the free radical molecule to render it harmless.8
In a recent study published in Nutrients using National Health and Nutrition Examination Survey 2005 – 2008 data, researchers found that adults who consumed cranberry beverage had better micronutrient intakes compared with adults who did not.9 Cranberry juice is not often recommended as an oral health-promoting product because of its tartness; the juice requires a bit of sweetener in order to be palatable. And as sugar and intense sweeteners come under fire, cranberry seems to be left at the curb even though it is extremely high in proanthocyanidins.
Cranberries are relatively low in fructose – the most controversial of all the natural sugars. A half-cup serving of dates contains about 55 grams of fructose, while the same amount of raisins has about 42 grams of fructose; dried cranberries have 40 grams; and prunes have 30 grams. Additionally, raw cranberries have 0.6 grams of fructose per 100 grams of fruit. Adding a metabolically supportive polyol like xylitol or erythritol may increase the benefits of a tart juice, such as cranberry.10, 11, 11b
Along with systemic benefits, the cranberry also has some topical benefits. By decreasing the hydrophobicity of the early colonizers,12 oral bacteria have trouble forming a biofilm in the presence of cranberry. Periodontal tissues respond positively to the presence of cranberry, as well. Early research is looking at cytokine expression of tissues undergoing a periodontal infection. Fibroblasts and epithelial cells react so well that cranberry researchers are looking to this tart fruit as a topical adjunct to periodontal therapy.13, 14, 15.
Cocoa and dark chocolate are also high in polyphenols16. Cocoa’s anti-inflammatory effects are being studied as a potential medicine in Frontiers in Pharmacology Experimental Pharmacology and Drug Discovery. “The mechanisms involved in the cardioprotective effects of cocoa flavonoids include reduction of oxidative stress, inhibition of low-density lipoproteins oxidation and platelet aggregation, vasodilatation of blood vessels, inhibition of the adherence of monocytes to vascular endothelium, promotion of fibrinolysis, and immunomodulatory and anti-inflammatory activity.”17
Not only do the studies of polyphenols in cocoa look at cardiovascular effects, they also examine the topical effects. Components in cocoa, tea and coffee reduce biofilm formation, as well as acids produced by Streptococcus mutans and S. sanguinis.18 In the meantime, chocolate continues to intrigue researchers, clinicians and consumers. As a drink, cocoa, cranberry or any dark berry-type fruit can support periodontal therapy or caries management strategy.
Resveratrol is a polyphenolic compound found in grapes, red wine, purple grape juice, peanuts and some berries, including cranberries. Some plants produce resveratrol in response to stress, injury, fungal infection or ultraviolet (UV) radiation.19 Resveratrol benefits are being studied in a variety of conditions: obesity,20 skin, inflammation, diabetes, aging, cancers of the breast and prostate, heart health and blood.19 (See image.)
Berries have other health benefits aside from reducing oxidative stress, increasing vascular elasticity or reducing biofilm formation, such as COX-2 inhibition. COX-2 is an enzyme responsible for inflammation and pain. After several very effective drugs targeting COX-2 inhibition were approved for marketing, data from clinical trials revealed that such drugs significantly increased heart attacks and strokes. While berries may not match pharmaceuticals, they cannot be ignored.21, 22 (See table.)
Animal and Vegetable Proteins
Let’s not forget proteins. Although many have been led to believe that protein only comes from meat and soy, many vegetables have a protein content that rivals beef.22
Proteins are important for tissue regeneration. As the body is used, muscle breaks down and must be rebuilt. Protein is very important for an active and/or growing human. In 2009, the American Dietetic Association reversed its long-held stance that vegetable proteins must be combined in order to approximate the protein profile of meat. That is no longer the stand. Studies have shown that one can consume enough protein from plant sources.23
Salmon is high in protein and considered a superfood. Salmon, mackerel, sardines, anchovies, herring and other fatty fish are high in Omega-3, EPA and DHA. These fatty fish components lower inflammation as part of a long list targeting health benefits. In people with any type of inflammatory condition, fatty fish should be included as a healthful food. Recent stories on farmed versus wild salmon indicate that farming methods have improved to the point where farm-raised salmon may be as healthful as wild.
Tea comes up in the health research quite often. Green, oolong or black, tea has some unique properties that carry them into the functional food category. Polyphenols in tea include catechins, theaflavins, tannins and other flavonoids. The main characteristic is the antioxidant property of tea high in phenol called catechin. Among the several types of catechin that exist, epigallocatechin gallate (EGCg) is the most powerful. Of the different types of tea, green tea contains much more EGCg than any other. In vitro studies have demonstrated that EGCg blocks carcinogenesis by affecting a wide array of signal transduction pathways.24, 25 In addition to the EGCg polyphenol, green tea contains other polyphenols that interfere with the expression of oxidative stress. The catechin in the tea has also been studied as an adjunct to traditional non-surgical periodontal therapy. Researchers concluded that green tea catechins can be used as an effective local drug delivery method. They can also be used for mechanical periodontal therapy in treatment of chronic periodontitis.26, 27
Using Functional Foods
Supplementing with a healthy diet is a first line of defense. However, many patients with periodontal disease, for instance, present with co-factors that may or may not be visible or yet diagnosed. A simple chairside blood test for c-reactive proteins as part of a blood panel can detect hidden inflammation such as arthritis, colitis, and a host of other inflammatory conditions that may be chronic and undiscovered. So, people with those conditions will benefit from a discussion on supporting functional foods, such as berries or supplements of phytonutrients.
C-reactive proteins are a measure of inflammation, and testing can be done with a simple finger nick. Studies on functional foods vary greatly in endpoints and inflammatory measurements. While it may be difficult to make definitive statements about any functional food, it will always be safe to recommend functional whole foods. The whole fruit contains the major isolate, anthocyanin, it as well as a host of micro nutrients that interact with each other for a synergistic biological effect, or counteract each other for potential homeostasis.
Functional foods can be communication tools for all health care providers, especially in dentistry, where the mantra has been so monotonous – brush, floss, avoid sugar – that people don’t hear it any longer. From chewing gum to xylitol-sprinkled blueberries covered with plain yogurt or green tea with a red wine chaser, patient engagement will continue to become easier with each new discovery and confirmation.
Glossary of terms
Anthocyanins: Degradation product of Anthocyanidins.
Bioactive: Bioactive refers to a substance having or producing an effect on living tissue.
Bioactive Compounds: Bioactive compounds are the naturally occurring chemical compounds contained in, or derived from, a plant, animal or marine source, that exert a desired health/wellness benefit (e.g., omega-3 fatty acids in flax or fish oils and beta-glucans from oats and barley).
Cytokines: Any of a number of substances, such as interferon, interleukin and growth factors, that are secreted by certain cells of the immune system and have an effect on other cells. Cells of the immune system communicate with one another by releasing and responding to chemical messengers called cytokines.
Flavonoids: Flavonoids, or bioflavonoids, are any large group of water-soluble plant pigments, including anthocyanins, which are beneficial to health.
Functional Foods: Functional foods are those that have a potentially positive effect on health beyond basic nutrition. These foods are similar in appearance to, or may be, a conventional food that is consumed as part of a usual diet, and are demonstrated to have physiological benefits and/or reduce the risk of chronic disease beyond basic nutritional functions (i.e., they contain bioactive compound).
Functional Ingredients: Functional ingredients are standardized and characterized preparations, fractions or extracts containing bioactive compounds of varying purity that are used as ingredients by manufacturers in food (human and pet) and preparations, fractions or extracts containing bioactive compounds of varying purity, which are used as ingredients by manufacturers in the cosmetics and pharmaceutical sectors.
Herbs: Herbs are the leaves, roots and flowers of plants grown and processed for culinary, cosmetic, industrial, medicinal, landscaping, decorative and fragrant purposes. Much of the early interest in functional foods and nutraceuticals was based on the medicinal uses of herbs.
Industrial Ingredients: Industrial ingredients are the standardized and characterized preparations, fractions or extracts of agri-commodities of varying purity that are used as ingredients by manufacturers of non-food products.
Lycopene: Lycopene is an antioxidant compound that gives tomatoes and certain other fruits and vegetables their color. It is one of the major carotenoids in the diets of North Americans and Europeans.
Natural Health Products: Natural Health Products (NHPs) include homeopathic preparations; substances used in traditional medicines; minerals or trace elements; vitamins; amino acids; essential fatty acids; or other substances derived from botanicals, animals or microorganisms. These products are generally sold in medicinal or “dosage” form to diagnose, treat or prevent disease; restore or correct function; or to maintain or promote health. As a product group, NHPs include nutraceuticals.
Novel Foods: Novel foods are products that have never been used as food; foods that result from a process that has not previously been used for food; or foods that have been modified by genetic manipulation, otherwise known as genetically modified foods.
Nutraceutical: Nutraceuticals are products isolated or purified from foods that are generally sold in medicinal forms not usually associated with foods. A nutraceutical is demonstrated to have a physiological benefit or provide protection against chronic disease.
Oxidative: Oxidative is the combination of a substance with oxygen – a reaction in which the atoms in an element lose electrons and the valence of the element is correspondingly increased.
PAC: Acronym for proanthocyanidin
Phytonutrients: “Phyto” comes from the ancient Greek word for plant. Phytonutrients are components that give a plant its color, taste and odor. Phytonutrients are also part of the plant’s self-defense system, protecting it from pests, viruses, bacteria and excessive sunlight. All plants – fruits, vegetables, grains, nuts, herbs and spices – contain a variety of phytonutrients.
Polyphenols: Polyphenols are a group of chemicals found in many fruits, vegetables and other plants, such as berries, walnuts, olives, tea leaves and grapes. They are classified as antioxidants, meaning they remove free radicals from the body. Polyphenols are a structural class of mainly natural, but also synthetic or semisynthetic, organic chemicals characterized by the presence of large multiples of phenol structural unit.
Prebiotics: Prebiotics are non-digestible food ingredients that are used as an energy source by beneficial bacteria found naturally in the body’s intestines.
Proanthocyanidin: Proanthocyanidin is a type of flavonoid found in many plants that can be used as a dietary supplement to enhance immunity and strengthen connective tissue.
Probiotics: Probiotics are live microorganisms (in most cases, bacteria) that are similar to the beneficial microorganisms naturally found in the human gut. These “good bacteria” are used to prevent and alleviate many different conditions, but particularly those that affect the gastrointestinal tract.
Resveratrol: Resveratrol is a polyphenol compound found in certain plants and in red wine that has antioxidant properties and has been investigated for possible anti-carcinogenic effects.
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26. Hattarki SA, Pushpa SP, Bhat K. Evaluation of the efficacy of green tea catechins as an adjunct to scaling and root planing in the management of chronic periodontitis using PCR analysis: A clinical and microbiological study. J Indian Soc Periodontol. 2013 Mar;17(2):204-9.
27. Kudva P, Tabasum ST, Shekhawat NK. Effect of green tea catechin, a local drug delivery system as an adjunct to scaling and root planing in chronic periodontitis patients: A clinicomicrobiological study. J Indian Soc Periodontol. 2011 Jan;15(1):39-45.