Pneumonia: A Nutrition and Natural Health Reference
1. Definition and Overview
Pneumonia is an infection that affects one or both lungs, causing the air sacs, or alveoli, of the lungs to fill up with fluid or pus. Bacteria, viruses, or fungi may cause pneumonia. More formally, pneumonia can be generally defined as an infection of the lung parenchyma in which consolidation of the affected part and a filling of the alveolar air spaces with exudate, inflammatory cells, and fibrin is characteristic.
Pneumonia is an umbrella term for a group of respiratory infections caused by several different microorganisms, ranging from bacteria, mycobacteria, fungi, and viruses, and they can all be acquired in different environments.
There are three main inflammatory patterns depending on the cause of pneumonia and the areas that are affected: lobar pneumonia, bronchopneumonia, and interstitial pneumonia. Lobar pneumonia affects an entire lobe of the lung, and the inflammatory response causes the accumulation of cells, protein, and fluids leaking out of nearby capillaries in the lungs and into the alveoli of the affected lobe.
2. Clinical Presentation and Symptoms
Symptoms can range from mild to serious and may include a cough with or without mucus, fever, chills, and trouble breathing. How serious pneumonia is depends on the individual's age, overall health, and what caused the infection.
Pneumonia typically presents as an acute illness (present for 21 days or less), usually with cough as the main symptom, and with at least one other lower respiratory tract symptom such as fever, sputum production, breathlessness, wheeze or chest discomfort or pain, and with no alternative explanation.
Older adults and people who have serious illnesses or weakened immune systems may not have the typical symptoms; they may have a lower-than-normal temperature instead of a fever, and older adults who have pneumonia may feel weak or suddenly confused. Sometimes babies do not have typical symptoms either; they may vomit, have a fever, cough, or appear restless or tired and without energy.
A chest X-ray looks for inflammation in the lungs and is often used to diagnose pneumonia. Pulse oximetry measures how much oxygen is in the blood, as pneumonia can keep the lungs from getting enough oxygen into the blood.
3. Body Systems Involved
3.1 Respiratory System
Once pathogens have invaded the alveoli, they multiply and cause an inflammatory response. White blood cells (neutrophils and macrophages) migrate to the infected alveoli, and this influx of cells and the replication of the causative organism leads to the consolidation seen in pneumonia β an exudate of cellular debris, microorganisms, and fluid filling the alveoli and bronchioles.
The consolidation and inflammation in the alveoli hinder the exchange of oxygen and carbon dioxide, leading to the symptoms of dyspnea and hypoxia.
3.2 Immune System
The resident macrophages serve to protect the lung from foreign pathogens, but ironically, the inflammatory reaction triggered by these very macrophages is responsible for the histopathological and clinical findings seen in pneumonia. The macrophages engulf pathogens and trigger signal molecules or cytokines like TNF-Ξ±, IL-8, and IL-1 that recruit inflammatory cells like neutrophils to the site of infection. They also present antigens to T cells that trigger both cellular and humoral defense mechanisms, activate complement, and form antibodies, which in turn causes inflammation of the lung parenchyma and makes the lining capillaries "leaky," leading to exudative congestion.
There is an intricate balance between the organisms residing in the lower respiratory tract and the local and systemic defense mechanisms (both innate and acquired), which when disturbed gives rise to inflammation of the lung parenchyma β pneumonia.
3.3 Nervous and Thermoregulatory Systems
The systemic cytokine release during pneumonia also acts on the hypothalamus in the brain and disrupts normal thermoregulation, causing fever and chills.
3.4 Cardiovascular System
To make it easier for immune cells to find and enter the site of infection from the bloodstream, the released cytokines cause dilation of nearby blood vessels, leading to increased blood flow and leaky capillaries. This inflammatory response aims to destroy invading pathogens and infected cells, but also causes damage to healthy lung tissue. In severe cases, severe infections can cause septic shock if the bacteria enter the bloodstream.
4. Contributing and Associated Factors
4.1 Age
Having an immune system that is not fully developed or one that has been weakened by age increases the risk of getting pneumonia and experiencing more serious illness; this is why both the very young (infants and babies younger than 24 months) and adults aged 65 or older are more likely to develop pneumonia.
4.2 Tobacco Smoking
Of 460,592 participants included across 27 studies in a systematic review and meta-analysis, meta-analysis showed that current smokers had a pooled odds ratio of 2.17 (95% CI 1.70β2.76) for developing community-acquired pneumonia. Smoking is an independent modifiable risk factor for developing community-acquired pneumonia, alongside other lifestyle factors including alcohol abuse, low body mass index, having regular contact with children, and poor dental hygiene. Current smoking has been associated with a wide spectrum of infectious diseases including bacterial pathogens such as Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, Staphylococcus aureus, Legionella pneumophila, and Mycobacterium tuberculosis, as well as viral pathogens including influenza and rhinovirus.
The mucociliary clearance is often impaired in cigarette smokers, post-viral states, Kartagener syndrome, and other related conditions, compromising a key airway defense mechanism.
4.3 Alcohol Consumption
A systematic review and meta-analysis found the risk of community-acquired pneumonia to be significantly increased in people who consumed alcohol at all or in higher amounts, relative to those who consumed no or lower amounts (pooled RR=1.83, 95% CI).
There are several possible mechanisms by which alcohol consumption increases pneumonia risk, including the sedative properties of alcohol which can reduce oropharyngeal tone, leading to an increased risk of aspiration of microbes; furthermore, high levels of alcohol intake can modify alveolar macrophage function, hence diminishing pulmonary defense against infection. Also, high alcohol consumption is often associated with malnutrition, as it interacts with nutrient metabolism and utilization, resulting in the impairment of immunity and increased community-acquired pneumonia risk.
4.4 Underlying Disease and Immunosuppression
Specific underlying medical conditions predispose individuals to pneumonia from suppression of the host immune system. These conditions include malignancies, active chemotherapy treatment, infection from HIV, organ transplant recipient status, and medications such as chronic glucocorticoids and biologic agents used for treatment of inflammatory conditions.
Patients with the following conditions have a higher risk of pneumonia despite adjustment for known risk factors and confounders: stroke or transient ischaemic attack, rheumatoid arthritis, Parkinson's disease, cancers, multiple sclerosis, dementia, and osteoporosis.
Lung diseases such as asthma, bronchiectasis, cystic fibrosis, or COPD also increase pneumonia risk, as do other serious conditions such as malnutrition, diabetes, heart failure, sickle cell disease, or liver or kidney disease.
4.5 Malnutrition
Underweight status, inadequate breastfeeding, lack of immunization, and indoor and outdoor air pollution are identified as risk factors for childhood pneumonia.
Globally, moderately underweight children hospitalized with pneumonia are twice as likely to die, and severely underweight children are four and a half times as likely to die compared with children with a normal weight. An estimated two in five children admitted to hospital with pneumonia in low-income and middle-income countries are moderately or severely underweight.
Undernutrition has been associated with unfavorable clinical outcomes in pneumonia, such as prolonged hospital stay, need for intensive care unit admission, and mortality.
4.6 Environmental and Crowding Factors
Most people get pneumonia when they catch an infection from someone else in their community. The chance of getting pneumonia is higher when living or spending a lot of time in a crowded place such as military barracks, prison, or homeless shelters.
A major epidemiological model for childhood pneumonia is based on the prevalence of five main risk factors within countries: malnutrition, low birth weight, non-exclusive breastfeeding in the first four months, solid fuel use, and crowding.
5. Nutrients, Herbs, and Natural Ingredients
5.1 Vitamin D
Traditional and Historical Context
Vitamin D was historically associated with bone and calcium metabolism. Its relevance to respiratory infection resistance became a focus of scientific investigation in the late 20th and early 21st centuries when epidemiological researchers noted correlations between low vitamin D status, geographic latitude, seasonality, and susceptibility to respiratory infections.
Scientific Evidence
Although vitamin D is best known for its role in calcium, phosphorus, and bone homeostasis, it has gained attention in recent years because of a wide range of extraskeletal effects, including its immunomodulatory and antibacterial potential.
Vitamin D supplementation did not shorten hospitalization or accelerate recovery in children with pneumonia, results consistent with earlier pediatric-focused reviews that reported no clear therapeutic effects. These findings suggest that although vitamin D may reduce the risk of developing infection, it is unlikely to substantially modify the clinical course once acute respiratory infections are established.
A randomized, double-blind, placebo-controlled trial examined oral vitamin D supplementation in 200 children with severe pneumonia. The intervention was oral vitamin D (1,000 IU for children under 1 year and 2,000 IU for children over 1 year) or placebo once a day for five days from enrollment. A separate community-based randomized controlled study in under-five children with pneumonia found that oral vitamin D (300,000 IU bolus dose quarterly) had some beneficial effect in the prevention of recurrent pneumonia in under-five children.
Laboratory and observational research studies suggest that vitamin D and marine omega-3 fatty acids may reduce risk for pneumonia, acute exacerbations of respiratory diseases including COPD or asthma, and decline of lung function, but prevention trials with adequate dosing, adequate power, and adequate time to follow-up are lacking.
As for vitamin D, supplementation has been shown to protect against the common cold overall, with patients with vitamin D deficiency and those not receiving bolus doses experiencing the most benefit. Overall, the body of evidence for vitamin D in pneumonia specifically is mixed; preventive signals exist in deficient populations but therapeutic benefit in established pneumonia has not been consistently demonstrated.
5.2 Vitamin C (Ascorbic Acid)
Traditional Use
Vitamin C has been used across multiple traditional medical systems as an immune-supporting remedy. Historical observations of scurvy β characterized in part by susceptibility to infections β established an early empirical link between vitamin C adequacy and resistance to respiratory disease.
Scientific Evidence
Five placebo-controlled trials have shown quite consistently that the duration and severity of common cold episodes are reduced in vitamin C groups, indicating that viral respiratory infections in humans are affected by vitamin C levels. Three controlled trials with human subjects reported a significantly lower incidence of pneumonia in vitamin C-supplemented groups, suggesting that vitamin C may affect susceptibility to lower respiratory tract infections under certain conditions.
For most people, vitamin C does not prevent colds and only slightly reduces their length and severity. Vitamin C has shown some promise for people under severe physical stress. The evidence for vitamin C specifically in pneumonia prevention or treatment remains preliminary and is not consistent across populations.
5.3 Zinc
Traditional Use
Zinc-rich foods β including shellfish, legumes, and seeds β have been part of traditional healing diets across many cultures. Indigenous healing systems in parts of Asia and Africa historically used zinc-containing mineral compounds to address respiratory ailments, though formal zinc supplementation as a discrete practice is a modern construct.
Scientific Evidence
Oral zinc lozenges may reduce the duration of the common cold when started within 24 hours of initial symptoms and taken for a time period of less than 2 weeks.
Zinc supplementation may shorten the duration of colds by approximately 33%, and CC patients may be instructed to try zinc within 24 hours of onset of symptoms.
An NIH-registered trial at Tufts University investigated zinc specifically for pneumonia prevention in the elderly (NCT05527899, "Zinc Intervention in Elderly for Prevention of Pneumonia," ZIPP), which was completed in 2024. Zinc products used in the nose, such as nasal gels and swabs, have been linked to a long-lasting or even permanent loss of the sense of smell and should not be used intranasally.
Some studies suggest that dietary patterns, malnutrition, and certain nutrients such as vitamins D, E, A, iron, zinc, selenium, magnesium, omega-3 fatty acids, and fiber may have a significant role in preventing respiratory diseases, alleviating symptoms, and lowering mortality rates. However, the evidence is not consistent and conclusive, and more research is needed to clarify the mechanisms and the optimal doses of these dietary components.
5.4 Vitamin A
Traditional Use
Vitamin A deficiency has been recognized as a major contributor to immune vulnerability in children since the early 20th century. Traditional healing in parts of Africa and Asia incorporated vitamin A-rich foods such as liver, palm oil, and green leafy vegetables specifically to address respiratory vulnerability in children β observations that preceded formal epidemiological documentation.
Scientific Evidence
A meta-analysis of 15 randomized controlled trials involving 3,496 pediatric patients found that vitamin A combined with conventional therapy improved clinical efficacy (P < .05), shortened the duration of fever and cough, the time to negative chest X-ray, and hospitalization duration. The included trials were predominantly from China, and many had methodological limitations including risk of bias, meaning results must be interpreted with caution and may not be generalizable globally.
5.5 Echinacea
Traditional Use
Echinacea species β particularly Echinacea purpurea, E. angustifolia, and E. pallida β were widely used by Indigenous peoples of North America, including the Plains tribes, to treat colds, respiratory infections, and other inflammatory conditions, typically as decoctions or poultices. European settlers adopted these practices, and the herb entered the Western phytomedicine tradition in the 19th century.
Scientific Evidence
A 2016 systematic review and meta-analysis found that echinacea might have a preventative effect on the incidence of upper respiratory tract infections, but it is unclear whether the effect is clinically meaningful; there was no evidence that echinacea changed the duration of upper respiratory tract infections.
A 2014 Cochrane review of 24 double-blind randomized controlled trials involving 4,631 participants concluded that echinacea products have not been shown to provide benefits for treating colds; although there is the potential that some preparations are more effective than placebo, the overall evidence for clinically relevant treatment effects is weak.
No robust clinical trials have specifically evaluated echinacea in bacterial or viral pneumonia. Its evidence base is confined to upper respiratory infections, and extrapolation to pneumonia specifically is not supported by current data. A 2023 systematic review concluded that echinacea may improve cold symptoms; however, the quality of the evidence was low to moderate. Taking echinacea for a short amount of time is probably safe, but some people may experience gastrointestinal side effects.
5.6 Elderberry (Sambucus nigra)
Traditional Use
Elderberry has an extensive history of use in European folk medicine for colds, coughs, and respiratory illness. Preparations included syrups, teas, and wines made from the berries and flowers. It was employed in traditional medicine across Central and Northern Europe long before any clinical investigation was conducted.
Scientific Evidence
Some preliminary research suggests that elderberry may relieve symptoms of flu or other upper respiratory infections; however, conclusive evidence from high-quality clinical trials is lacking. Taking elderberry may be helpful for cold and influenza symptoms and may result in a quicker recovery from illness; however, the quality of the evidence is low because only a few small studies have been conducted.
No published clinical trials have specifically evaluated elderberry in confirmed pneumonia cases. Evidence is confined to upper respiratory viral infections and is of low to moderate quality. Extrapolation to pneumonia is speculative.
5.7 Garlic (Allium sativum)
Traditional Use
Garlic has been used as a medicinal food in virtually every major traditional medical system, including Traditional Chinese Medicine, Ayurveda, ancient Greek medicine, and Middle Eastern healing traditions. It was applied as a respiratory remedy in the form of raw cloves, decoctions, and poultices β often specifically for coughs, congestion, and febrile respiratory illness. Its antimicrobial properties were empirically recognized for centuries before modern science identified allicin as its primary bioactive constituent.
Scientific Evidence
Several studies have shown that garlic can be effective against influenza A and B, HIV, HSV-1, viral pneumonia, and rhinovirus in laboratory settings. However, these are largely in vitro findings.
Approaches for which the evidence is conflicting, inadequate, or mostly negative include vitamin C (for most people), echinacea, garlic, and American ginseng, according to NCCIH. Previous reviews suggest that echinacea might have a preventative benefit for upper respiratory tract infections, including the common cold, but whether any reported effect is clinically meaningful is debatable. For garlic specifically in pneumonia, human clinical trial data are sparse, and existing findings do not support definitive clinical claims.
5.8 Honey
Traditional Use
Honey is one of the oldest traditional remedies applied for microbial infections, due to its antibacterial, anti-inflammatory, and antioxidant properties. Anecdotal evidence has suggested that honey can be used to treat colds in general and coughs in particular, with people having used it as a therapy for thousands of years.
Scientific Evidence
A systematic review by researchers at the University of Oxford found that honey is superior to usual care in the treatment of acute upper respiratory infection, concluding it could offer a viable alternative to prescribing an antibiotic, supporting efforts to reduce antimicrobial resistance.
Honey can prevent and relieve the symptoms of respiratory tract infections, as well as gastrointestinal and cardiovascular diseases, due to its antioxidant, anti-inflammatory, antiviral, and antibacterial effects. In the context of respiratory tract pathogens, in vitro studies have shown antibacterial and antibiofilm effects of multiple honey types against common respiratory pathogens including Streptococcus pneumoniae, Haemophilus spp., and Pseudomonas aeruginosa.
Evidence supporting honey in pneumonia specifically β as opposed to upper respiratory infections β is largely in vitro or derived from studies of upper respiratory tract infections. Clinical trial evidence at the level of confirmed pneumonia is not yet established. Honey has been used for many years as a traditional remedy for upper respiratory tract infection, although clear evidence for its effectiveness is lacking.
5.9 Omega-3 Fatty Acids
Traditional and Dietary Context
Fish and marine foods rich in omega-3 fatty acids (EPA and DHA) form the basis of traditional diets in many coastal populations. Cod liver oil was historically administered as a general tonic and respiratory remedy in Scandinavian and Northern European traditions.
Scientific Evidence
Laboratory and observational research studies suggest that marine omega-3 fatty acids may reduce risk for pneumonia, acute exacerbations of respiratory diseases including COPD or asthma, and decline of lung function, but prevention trials with adequate dosing, adequate power, and adequate time to follow-up are lacking.
The recommendation for omega-3 fatty acid supplementation for COVID-19 pneumonia treatment awaits further evidence, and currently there is insufficient clinical evidence to definitively establish the efficacy of omega-3 supplementation for combating viral respiratory infections.
5.10 Probiotics
Traditional and Dietary Context
Fermented foods β including yogurt, kefir, miso, kimchi, and traditionally fermented porridges β have been consumed across many cultures for their perceived health-supporting properties. Their application to respiratory health is a more recent traditional attribution, though gut-respiratory axis connections are now an active area of scientific research.
Scientific Evidence
Specific probiotics have been suggested to be effective in alleviating the duration and severity of acute rotavirus gastroenteritis, and increasing evidence shows that probiotics are beneficial in respiratory tract infections, which in most cases are of viral origin. Probiotics may also show direct antimicrobial activity against pathogens by producing antimicrobial substances such as organic acids, hydrogen peroxide, biosurfactants, and bacteriocins.
Due to reports of significant antiviral activity, fermented foods and associated probiotic microorganisms have recently received a lot of attention. Several probiotic strains showed a diverse variety of antiviral properties and modes of action, and the probiotic bacteria and bioactive ingredients in fermented products have antiviral capabilities that can combat viruses that affect the digestive and respiratory systems.
The lack of consistent evidence between probiotic strains/genera and even within strains may be due to variation in study designs and reported outcome measures, the length of intervention, and study populations used (children vs. adults). Evidence for probiotics specifically in pneumonia remains preliminary, and no definitive clinical conclusions can be drawn for this indication.
5.11 N-Acetylcysteine (NAC)
Traditional and Pharmacological Context
N-acetylcysteine is a derivative of the amino acid cysteine. It is not a traditional herbal preparation; however, it is frequently discussed in natural health contexts as a mucolytic and antioxidant compound.
Scientific Evidence
N-acetylcysteine is a mucolytic agent commonly administered with antibiotics for the treatment of lower respiratory tract infections, which has been demonstrated to exert antimicrobial and antibiofilm activity against relevant respiratory pathogens. Its use in respiratory care is well established in conventional clinical practice, though evidence specifically for its role in improving pneumonia outcomes (as opposed to COPD or bronchiectasis) is more limited and often adjunctive.
5.12 Selenium
Scientific Evidence
In studies of respiratory syncytial virus infection, days needed for symptom relief and recovery were fewer in the selenium supplement group than in controls; it was concluded that selenium supplements can promote recovery from RSV infection. Zinc supplementation and probiotics emerge as potential preventive measures for both COVID-19 and viral respiratory infections, with selenium demonstrating promising results in treating viral respiratory infections.
Key dietary components such as vitamins C, D, E, zinc, selenium, and omega-3 fatty acids have well-established immunomodulatory effects, with benefits in infectious disease. However, evidence for selenium specifically in pneumonia is limited primarily to in vitro and animal studies, with human clinical trial data in pneumonia remaining sparse.
6. Dietary and Lifestyle Factors
6.1 Malnutrition and Nutritional Status
Older inpatients with pneumonia frequently present with malnutrition when assessed by recognized nutritional screening tools, and nutritional status is strongly associated with clinical outcomes.
Undernutrition has been associated with unfavorable clinical outcomes in community-acquired pneumonia, such as prolonged hospital stay, need for intensive care unit admission, and mortality. Although recent studies have found that nutritional assessment at the time of hospital admission and appropriate treatment are important aspects of patient care in medical wards, most studies evaluating risk factors for complications in community-acquired pneumonia and severity scales do not include patients' nutritional status.
A six-month individualized nutritional intervention program under dietitian and patient family nutritional support for malnourished older adults with pneumonia can significantly improve their nutritional status and reduce the readmission rate.
6.2 Breastfeeding
Non-exclusive breastfeeding in the first four months of life is one of the five main risk factors for childhood pneumonia, alongside malnutrition, low birth weight, solid fuel use, and crowding. This places breastfeeding in the category of a strongly evidence-supported protective nutritional practice for pneumonia prevention in infants.
6.3 Smoking Cessation
Evidence from systematic reviews supports recommendations for smoking cessation as well as avoidance of passive exposure to tobacco smoke, particularly in persons at high risk of developing pneumonia. Patients who recover from an episode of community-acquired pneumonia are recognized to be at risk of recurrent episodes; therefore, hospitalization with pneumonia provides a valuable "teachable moment" when smoking cessation should be promoted.
6.4 Alcohol Reduction
There are several possible mechanisms to explain the observation that alcohol consumption increases the risk of pneumonia, including the sedative properties of alcohol which can reduce oropharyngeal tone, leading to an increased risk of aspiration of microbes; furthermore, high levels of alcohol intake can modify alveolar macrophage function, hence diminishing pulmonary defense against infection. High alcohol consumption is often associated with malnutrition, as it interacts with nutrient metabolism and utilization, resulting in the impairment of immunity and increased community-acquired pneumonia risk.
6.5 Broader Dietary Patterns
A narrative review summarizing the current literature on the association between dietary intake, serum levels of micronutrients, malnutrition, and dietary patterns and respiratory infections β including flu, pneumonia, and acute respiratory syndrome β found that some studies suggest dietary patterns, malnutrition, and certain nutrients such as vitamins D, E, A, iron, zinc, selenium, magnesium, omega-3 fatty acids, and fiber may have a significant role in preventing respiratory diseases, alleviating symptoms, and lowering mortality rates. However, the evidence is not consistent and conclusive, and more research is needed to clarify the mechanisms and the optimal doses of these dietary components.
6.6 Indoor Air Pollution
Indoor and outdoor air pollution, alongside underweight status and inadequate breastfeeding, are identified as risk factors for childhood pneumonia. Exposure to cooking smoke and biomass fuel combustion products is a recognized modifiable environmental risk factor in lower-income settings.
6.7 Dental Hygiene
Previous systematic reviews have reported that smoking is an independent modifiable risk factor for developing community-acquired pneumonia alongside other lifestyle factors including alcohol abuse, low body mass index, having regular contact with children, and poor dental hygiene. Poor oral hygiene is thought to increase the oropharyngeal microbial burden available for aspiration into the lower respiratory tract, contributing to pneumonia risk, particularly aspiration pneumonia.
7. Summary of Evidence Strength
- Vitamin D: Moderate evidence from multiple RCTs and meta-analyses supports a potential preventive role, particularly in deficient individuals; therapeutic benefit in established pneumonia is not consistently demonstrated. Evidence is stronger for deficient populations.
- Vitamin A: Meta-analysis of 15 RCTs in pediatric pneumonia shows clinical benefit as an adjunct to conventional therapy; most trials are from China and have methodological limitations.
- Zinc: Preliminary evidence for reducing duration of upper respiratory infections; specific pneumonia evidence in humans is limited; a dedicated trial in elderly populations was recently completed (Tufts/NIH, 2024).
- Vitamin C: Preliminary signals in controlled trials for reducing pneumonia incidence under certain conditions; insufficient evidence for general use in pneumonia treatment.
- Echinacea: Weak and conflicting evidence for upper respiratory infections; no robust pneumonia-specific clinical trials.
- Elderberry: Low-quality evidence for upper respiratory infections and influenza symptom relief; no pneumonia-specific clinical trials.
- Garlic: Predominantly in vitro evidence for antimicrobial activity; human clinical evidence for pneumonia is absent or insufficient.
- Honey: Superior to usual care for upper respiratory tract infections (Oxford systematic review); in vitro antibacterial evidence for respiratory pathogens; pneumonia-specific clinical trial data are absent.
- Omega-3 fatty acids: Laboratory and observational signals for pneumonia risk reduction; clinical trial evidence insufficient to support definitive recommendations.
- Probiotics: Promising preliminary evidence for respiratory viral infections; pneumonia-specific evidence weak; strain and study variability limit conclusions.
- Selenium: Promising in studies of RSV recovery; pneumonia-specific human clinical evidence is sparse.
- NAC: Established mucolytic agent with adjunctive antimicrobial and antibiofilm activity; clinical evidence specific to pneumonia outcomes is limited.
References
- NHLBI, NIH β What Is Pneumonia?
- NHLBI, NIH β Pneumonia Symptoms
- NHLBI, NIH β Pneumonia Causes and Risk Factors
- StatPearls (NIH/NCBI) β Pneumonia Pathology
- BC Campus Open Education β Pathophysiology of Pneumonia
- Medscape β Bacterial Pneumonia: Background, Etiology, Pathophysiology
- PMC β Identification of New Risk Factors for Pneumonia: Population-Based Case-Control Study
- PMC β Epidemiology, Etiology, and Risk Factors of Bacterial Pneumonia
- PMC β Epidemiology and Etiology of Childhood Pneumonia in 2010
- PMC β Prevalence and Impact of Malnutrition on Outcomes in Under-Five Children with Pneumonia
- MDPI Nutrients β Effect of Undernutrition and Obesity on Clinical Outcomes in Adults with Community-Acquired Pneumonia
- PMC β Effect of Nutritional Intervention Programs on Nutritional Status and Readmission Rate in Malnourished Older Adults with Pneumonia (RCT)
- PMC β Role of Vitamin D in Prevention and Treatment of Acute Respiratory Infections in Pediatric Populations: Systematic Review and Meta-Analysis
- PubMed β Effect of Vitamin D Supplementation in the Prevention of Recurrent Pneumonia in Under-Five Children (RCT)
- PubMed β Vitamin D Supplementation for Severe Pneumonia β A Randomized Controlled Trial
- PMC β Impact of Vitamin D Supplementation on Clinical Outcomes of COVID-19 Pneumonia Patients (RCT)
- PubMed β Lung VITAL: Vitamin D and Marine Omega-3 Fatty Acids on Pneumonia Risk in Adults
- PMC β Vitamin A in Children's Pneumonia: Systematic Review and Meta-Analysis of 15 Trials
- NCCIH, NIH β Colds, Flu, and Complementary Health Approaches
- NCCIH, NIH β The Common Cold and Complementary Health Approaches: What the Science Says
- CDC Yellow Book β Complementary and Integrative Health Approaches
- PMC β Select Dietary Supplement Ingredients for Preserving and Protecting the Immune System in Healthy Individuals: A Systematic Review
- PubMed β Self-Care for Common Colds: Vitamin D, Vitamin C, Zinc, and Echinacea in Immune Clusters
- PMC β Alcohol and the Risk of Pneumonia: A Systematic Review and Meta-Analysis
- PMC β Lifestyle Risk Factors for Invasive Pneumococcal Disease: A Systematic Review
- PMC β Effect of Tobacco Smoking on the Risk of Developing Community-Acquired Pneumonia: Systematic Review and Meta-Analysis
- PMC β Causal Association of Smoking, Alcohol, and Coffee with Risk of Bacterial Pneumonia: Mendelian Randomization Study
- PMC β Probiotics in Respiratory Virus Infections
- ScienceDirect β Effectiveness of Nutritional Supplements in Preventing and Treating COVID-19 and Viral Respiratory Infections
- PMC (BMC Public Health) β Dietary Patterns and Micronutrients in Respiratory Infections Including COVID-19: A Narrative Review
- PMC β In Vitro Antibacterial and Antibiofilm Activity of Hungarian Honeys against Respiratory Tract Bacteria
- Wiley Prescriber β Is Honey Effective for Upper Respiratory Tract Infection?
- PMC β Activity of N-Acetylcysteine Alone and in Combination with Colistin against Pseudomonas aeruginosa Biofilms
- NCBI Bookshelf β Pneumonia in Adults: Diagnosis and Management
- eClinicalMedicine (The Lancet) β Nutritional Supplementation in Children with Severe Pneumonia in Uganda and Kenya (COAST-Nutrition RCT)
Go back