BALANCING ORAL HEALTH AND NUTRITION IN THE TIME OF COVID-19
AGRIMA THAKUR1, UMA CHITRA2, PRASAD CHITRA3*
1, 3 Department of Orthodontics and Dentofacial Orthopaedics, Army College of Dental Sciences,
Secunderabad, India
2 Extension and Training Division, ICMR- National Institute of Nutrition, Hyderabad, India
ABSTRACT
Oral health is an important factor in the initiation and progression of many systemic diseases. Lack of oral health maintenance can have a number of adverse effects on the body, such as progression of upper respiratory and cardio-vascular diseases and enhancement of systemic illnesses such as diabetes. These factors can put patients at risk for contacting COVID-19; hence it is essential that the role of oral health be highlighted in conventional literature. The mouth also is the most important pathway for providing nutrition in order to improve the body’s immune response, which in turn is an essential requirement against viral infection. This paper investigates the correlation between COVID-19 and oral health, the importance of maintaining a healthy mouth and adequate nutrition. The specific micro and macro nutrients that have been found to be of increased value to COVID-19 patients and the general population are also discussed.
Keywords: Oral health, Nutrition, COVID-19, Nutrition therapy, Periodontitis, Systemic health
INTRODUCTION
Health is the most important determinant when it comes to assessing quality of life. In December 2019, when a group of patients with symptoms of pneumonia of unknown etiology were admitted to the Wuhan General hospital, nobody could have predicted that it would be the beginning of a global pandemic, affecting millions of people. It led to life threatening outcomes for not only medically compromised persons, but perfectly healthy, young individuals with competent immune systems were also severely affected all across the world. 1
The Novel Coronavirus strain alters the human immune system. It causes response- reaction changes in the body which leads to autoimmune damage of lung connective tissue.
Fast and highly contagious spread of this disease, paired with other factors like complicated and under-researched drug therapy and lack of health care infrastructure available in
India to deal with it, has made it imperative for us to adopt strategies that will help boost immune response in order to overcome the disease. 1
Immune response of the body is its ability to recognize and defend itself against pathogens.
The oral cavity is the most important pathway for obtaining nutrition which has an important role in developing or improving immune response. The preventive strategies for COVID-19 infection pertain to 2 basic steps- minimizing exposure, and maintaining/
boosting immunity. If there is one thing that we have learnt during this on-going pandemic, it is that prevention is far better than cure. Oral health is directly linked to health of the body. Both these factors, along with strong immune response, act synergistically in reducing morbidity in COVID-19 patients. The aim of this review is to highlight the potential role of oral health and nutritional status in preventing or reducing the severity of COVID-19, with additional focus on oral nutritional support.
THE IMPORTANCE OF ORAL HEALTH
Oral health has a great impact on general health. The American Heart Association has proposed two possible mechanisms that explain the role of periodontal health in progression of heart diseases, categorizing them as direct and indirect. 2 A systemic inflammatory response is triggered by periodontal diseases, leading to cytokines such as IL- 1beta, IL-6, IL-8, TNF-alpha and monocyte chemotactic protein- being released in the blood stream. This is considered to be the ‘indirect’ way in which periodontal diseases cause systemic changes in the body. The direct mechanism occurs when common everyday activities, such as brushing teeth, chewing or flossing, leads to oral microbes gaining access into the body’s circulatory system. This results in a state of transient bacteremia, with the risk of microbes lodging and colonizing at critical sites throughout the body. 3 These microbial products and cytokines, which have been released in response to oral infection, are also responsible for causing inflammation in other body organs, thus enhancing the development of systemic diseases like diabetes, rheumatoid arthritis, Alzheimer’s disease, chronic kidney and liver diseases and respiratory syndromes. 4
PANDEMIC PERSPECTIVE
Several other pathways which are directly linked to oral health or hygiene maintenance are critical in the up-keep of systemic health. Ventilator- Associated pneumonia (VAP) is one such condition, in which critically ill patients that are dependent on mechanical ventilation in ICU setups, acquire symptoms of pneumonia. Bacterial accumulation of Staphylococcus aureus and Pseudomonas aeruginosa in dental plaque is one of the main reasons for their accumulation in the trachea and bronchus, which in turn are important reservoirs of infection causing VAP. 5 Oral cavity commensals like Candida albicans and other fungus may be the cause for the increasing number of fungal infections as a complication of COVID-19 recovery. 6, 7 Shortage of antifungal medication is resulting in severe complications. The oral health status of critically ill patients is an important factor causing these conditions, which is often neglected in the clinical setup. 7 Improvement in oral hygiene and better oral health care can reduce the risk of development of critical respiratory conditions detrimental for the morbidity of COVID-19 patients, particularly the elderly and immune compromised, who are the most vulnerable groups. 4 Thus, frequent professional dental hygiene maintenance and other treatments can improve overall health of patients by reducing the colonization and mobilization of oral microbes at other sites of the body. 3
There is a two way relationship between periodontitis and diabetes, in which periodontitis negatively affects glycemic control due to inflammatory responses or infections, and patients with diabetes seem to be under increased risk of periodontal disease. 8, 9 Diabetes is being reported as a routine feature in many patients with critical COVID- 19 infection, who are developing severe pneumonia with a higher neutrophil and lower lymphocyte count.10
ORAL LESIONS IN COVID-19
Presence of oral lesions has been reported in many patients of Covid-19, and this further emphasizes the need for attention to be directed towards the oral cavity. They range from vesiculo- bullous lesions (painful ulcers and blisters) 11 to those resembling erythema multiforme 12, seen on almost all types of mucosa, with the maximum occurrence being noted on the masticatory mucosa 13. These lesions could be the result of factors such as stress due to social-life restrictions during the COVID-19 pandemic lockdown, lack of oral
hygiene, work pressure, or herpes simplex virus. 11 Another recurring condition being seen is fungal infections especially mucormycosis, an opportunistic but frequently fatal infection perpetrated by the heavy use of antibiotics and steroids. 14 Rhino- cerebral mucormycosis, which is the most prevalent form of this infection, has manifestations in the oral cavity. The negative detriments of COVID-19 pandemic, such as limited but expensive medical resources, reduced public transport and shortage in production and delivery of essential goods, to name a few, have further reduced the already poor access to oral health for everyone. As a consequence, oral health is being drastically affected during this pandemic, causing deterioration in general health and nutritional status. 15, 16
THE ROLE OF NUTRITION
Systemic nutrition plays an essential role in the treatment regimen of a majority of chronic diseases. It is a unique form of defense which constantly exerts its effect even when there isn’t an active pathogen at play and is especially important in ailments that do not have a properly designed, etiology- based treatment protocol. 17 Malnutrition is a chief reason for immunodeficiency worldwide. It is a serious issue that can cause damaging effects on the population, and this is especially important in the current pandemic scenario, since COVID- 19 effects are more profound and exaggerated in cases with malnutrition. 18 An important indicator of malnutrition, lymhopenia, has been found to be a negative factor for the prognosis of this infection. 19
While no known groups of the population are immune to this disease, clinical examination, history of other respiratory- related contagious diseases and overall epidemiologic experience can indicate high- risk groups. For example, according to the European Society for Clinical Nutrition and Metabolism (ESPEN), obesity is a dangerous condition for COVID-19 and is one of the prominent factors increasing disease mortality. 20 According to a report by Peng et al, a high Body Mass Index (BMI) score was related to poor prognosis in comorbid patients with COVID-19. 21 Patients having conditions that reflect upon their underlying protein- malnutrition status like chronic diabetes, recurrent infections or organ failure seem to have the most severe cases of COVID-19, however, in-spite of these reports the victims of Coronavirus are from all sections of society, irrespective of age, profession or
geographic location. Therefore, ensuring a competent immune system via nutrition is the closest we can get to a solid solution.
RISK FACTORS FOR UNDERNUTRITION IN COVID-19
COVID- 19 is not just a public health crisis, but also a grave economic and social issue. The most severe implications of any disaster have always been on vulnerable groups of society namely low- income households, the aged, immune-compromised and women and children.
Countless households have been pushed into economic despair, and the prediction by Oxfam is that about half a billion people across the world may end up in a state of poverty.
22 It is estimated by United Nations World Food Program that, by the end of the year 2021, 265 million people may face the threat of acute food insecurity, which is defined as the constant concern or worry about access to adequate food that is affordable and nutritious.
23 Many factors other than poverty have also added to the increasing state of under- nutrition worldwide. Restrictions on the means of production and delivery because of lesser agricultural productivity during lockdown and disturbances in the import–export chain have increased the cost of food. 24 As a result of these outcomes, low- income families are more likely to turn towards cheaper and easily accessible processed food, which is generally high in fat, sodium and sugar, and all-together less-nutritious, hence, furthering the deleterious health consequences. 22
THE AT- RISK COHORT
The maximum impact of the disease has been in older, immune-compromised individuals. A few reasons for this are discussed by Naja et al. 25 Firstly, patients aged 60 years or older having preexisting ailments such as diabetes, chronic lung disorders, or heart diseases are most likely to contact severe coronavirus infection compared to other groups. Second, the social distancing rules/ ‘stay home’ recommendations laid down by governments have had greater consequences on these groups, since they have become home bound, experiencing a sedentary lifestyle and somnolence for a prolonged period of time. Third, elderly patients
with chronic diseases may also be at a risk of malnutrition owing to their limited ability to purchase/ consume healthy food or due to compromised oral status. Therefore, at the community level, it is important to recognize such groups as ‘high risk’ and extend support to them in terms of food availability via reliable support groups. 25
PATHWAYS FOR THE ORAL- NUTRITION RELATIONSHIP
Dental caries and periodontal disease can lead to tooth loss, which can in turn cause difficulty in chewing because of limited occlusive contacts or lack of prosthesis. Chewing difficulty has a huge impact on people’s dietary habits and quality of nutrition intake, as food which is soft or easy to chew is preferred by these patients. 26, 27 Pain is one of the most common symptoms experienced in the oral cavity, which can occur as a result of caries, soft-tissue lesions, periodontal disease, temporo-mandibular joint disorders, ill- fitting prostheses or a variety of other reasons. Oral pain heavily influences the diet and subsequent nutritional status. Other conditions, such as xerostomia and altered taste also contribute to changes in nutrient intake. 28 The oral-nutrition relationship can be explained on the basis of Figure 1.
Figure 1- Relationship between the oral cavity and Nutrition (round areas are factors that affect nutrition indirectly via their impact on oral health)
The deterioration of dental health, especially in older individuals, causes not just impaired oral function but also increased body fatigue and high morbidity. The accumulated lifelong experience of periodontal diseases and dental caries in these patients reflects their underlying lifestyle, socio-economic status and attitude towards dental health. Evidence supports the notion that edentulousness, whether partial or total, has often led to deterioration in health and maybe a potential predictor of mortality. However, a conclusive deduction of this is yet to be reported. 29, 30
In many cases reporting from COVID-19 ICU settings, it has been demonstrated that around 23-60% of elderly patients were malnourished. 30 ESPEN have issued nutrition therapy guidelines that recommend Early Enteral Nutrition (EEN) for elderly patients
suffering from COVID-19 since it is superior to early Parenteral Nutrition (PN) or delayed Enteral Nutrition (EN). 31 Another report, however, states that such patients are unable to acquire EEN while in hospital, due to issues like chewing disturbances or oral ulceration due to the prolonged hospital stay, making recovery even more challenging. 31 This fact elaborates further on the need for a healthy dentition and oral cavity, which can enable health-care providers to deliver EEN more promptly.
NUTRITIONAL SUPPORT FOR THE GENERAL POPULATION
The pandemic has caused many adverse changes in people’s daily lives; but some simple measures in the form of a diet oriented towards improving immune status can be taken to maintain a healthy lifestyle during these difficult times. Daily diet and nutrition has a big influence on the immune competence of the body and can regulate the risk and severity of acquired infections. Protein and energy malnutrition, deficiency of specific micronutrients and minerals causes increased susceptibility to infection. Fulfillment of the daily adult calorie requirements and an adequate intake of vitamins A, E, B6, and B12, zinc and iron is most important for preventing this. 32 In addition to healthy eating, physical activity, getting adequate sleep and stress relief is also required.
ROLE OF SPECIFIC MICRONUTRIENTS
Micronutrients are substances which are required in trace amounts by the body, but have a huge impact on overall immunity. They function through various pathways to bring about both adaptive and innate immune response. For example, Vitamins A, B6, B12, C, D, E and zinc are essential for the structural integrity of mucosal barriers and the skin. Production of antibodies and recognition and destruction of external pathogens are also facilitated by these micronutrients. In addition, they play a role in the differentiation, proliferation, migration and normal function of T and B lymphocytes, thus improving cell mediated immunity. Zinc and selenium, along with vitamins C and E prevent damage due to free radicals produced in the organs when the body is in a state of increased oxidative stress. 33
Some specific micronutrients that are being increasingly recommended for intake for COVID-19 prevention are discussed.
Vitamin D- it is an antioxidant found to be associated with a reduction in occurrence and severity of pulmonary infections. 34 The limited nutrition- related COVID-19 literature reveals that deficiency of Vitamin D has been linked to the severity of the disease. Some reasons for this could be due to altered activation of T- cells and dendritic cells, or decreased chemokine production. This vitamin is mainly synthesized in the body when skin is exposed to ultraviolet B radiation. Italian Nutrition Society has recommended 15- 30 minutes of daily exposure to sunlight to fulfill the body requirement of vitamin D during this pandemic. 35
Vitamin C- supplementation of this has been found to be useful for those at risk of viral respiratory infections. The antioxidant property of vitamin C can enhance chemotaxis and phagocytosis, ultimately causing microbial killing. While there aren’t any specifically defined intake values in COVID-19 literature yet, increased intake of this vitamin in the form of citrus fruits has been recommended for all age groups. 33
Zinc, selenium- they are antioxidant micronutrients. Zinc is a cofactor of superoxide dismutase, an enzyme that suppresses oxidative stress. It generates both innate and humoral antiviral responses against many viruses, particularly the influenza virus. 36 Selenium increases glutathione peroxidase activity, which is an antioxidant enzyme.
Further actions include augmentation of several host immune responses, such as T- cell proliferation, interferon C production, and antigen stimulation. In an experimental study, selenium deficiency in mice afflicted with influenza virus led to an increased pro-inflammatory immune response, resulting in more severe disease.
37 Thus, it can be concluded that zinc and selenium act synergistically in reducing the symptoms of colds.
Fatty acids- intake of saturated fatty acids is favorable for low-grade inflammation, whereas mono and polyunsaturated fatty acids enhance immune-modulatory action.
Omega-3 polyunsaturated fatty acid, which is present in seafood and flaxseed activates both innate and adaptive immune cells, while the omega-9
monounsaturated fatty acid found in nuts, sunflower, safflower and olive oils have antiviral, antimocrobial and antioxidant effects. 38 It is recommended that consumption of saturated fatty acids, which are harmful for the immune system, be decreased and replaced by other unsaturated fatty acids during COVID- 19 for at risk as well as general population groups.
RECOMMENDATIONS FOR GENERAL PUBLIC HEALTH
Foods within each food group and across all the food groups to be consumed
Fruits and vegetables provide plenty of vitamins and minerals as well as fiber that are needed for a healthy diet. A diet rich in whole grains, nuts, and healthy fats such as in sunflower, sesame, groundnut or other oils rich in unsaturated fatty acids should be taken. Such diets support the immune system and help to reduce inflammation.
Food hygiene
COVID-19 is not a food-borne disease and there is no evidence that it can be spread through contact with purchased food. However, there is risk of aerosols carrying the virus particles remaining on the food bought publically, thus, ensuring food safety practices is important. Some measures to ensure this include:
(1) keeping food clean;
(2) separating raw and cooked foods;
(3) cooking food thoroughly;
(4) keeping food at safe temperatures;
(5) using safe water and raw materials to prepare foods.
Hydration
There is a direct association between hydration status and health. Water is most essential for cognitive function, body temperature control, cellular homeostasis, mood regulation, kidney, GI and heart function, and headache prevention. Staying well hydrated, mainly through drinking ample amounts of plain water (6-8 glasses a day for most adults) is recommended.
Regulating the intake of fats, sugar and salt
A number of people use food as a source of comfort in times of high stress, which can lead to overconsumption. Moreover, comfort foods are also very palatable because they are high in fat, sugar, salt and calories. These must be avoided as far as possible or their intake restricted.
Fiber
Fiber contributes to a healthy digestive system and offers a prolonged feeling of fullness, which helps prevent overeating. To ensure adequate fiber intake, vegetables, fruits, pulses and wholegrain foods must be included in all meals.
Maintaining ideal body weight
A BMI less than 18.5 is classified as undernourished, and more than 25 is overweight. Being underweight or overweight/obese impairs immunity and increases inflammation. Latest evidence reveals that obesity can be considered as an independent risk factor for contacting COVID-19 and the symptoms for such patients and more severe. 39 Thus, management of weight is of serious importance.
For patients with chronic systemic illness
People with diabetes or other chronic illnesses such as hypertension and kidney disorders should continue their regular medication with prescribed healthy dietary patterns along with adequate physical activity and keep themselves stress free.
Since these patients are more vulnerable to COVID-19, they should strictly follow hand hygiene and social distancing.
THE WAY FORWARD
It is said that the way to a person’s heart is through their mouth. This holds true even in the scientific context, since a healthy mouth with healthy mucosa is essential to the body’s immune status. Such an individual will not only be in a better position to ingest all types of healthy food, but will also be in a state of mental, physical and social well-being.
The second wave of COVID-19 has caused great distress to medical resources in India and other developing nations. Therefore, actions by individuals that will enable them to
minimize infection risk and maximize their ability to battle the clinical course of the disease must be encouraged by health- care providers.
ACKNOWLEDGEMENT None
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