What are infectious diseases?
Infectious diseases are human illnesses caused by microbial agents that can be transmitted from one person to another, either through direct contact or through the environment (e.g. infected air, water, food, objects, and surfaces). Some microbes are helpful and are required for normal bodily function, particularly in the gut. Others, under the right conditions, cause human illness. These illnesses range from benign conditions like folliculitis or skin infections, to long-standing and chronic infections (e.g., tuberculosis, leprosy, Lyme disease), to rapidly fatal illness (e.g., SARS, septic shock).
How could diet affect the immune system and susceptibility to infectious disease?
Malnutrition, the inadequate intake of calories and/or protein, is the most common cause of immunodeficiency, which increases the risk of contracting an infectious disease. Similarly, being deficient in certain micronutrients, especially vitamin-a, vitamin-e, vitamin-d, folate, and zinc, increases susceptibility to infections.[1] Consumption of raw, unwashed, inadequately cooked, or contaminated plant material, dairy, or meat is a common mode of acquiring infections from microbes like E. coli, Shigella, Salmonella, Listeria, Campylobacter, hepatitis A virus, norovirus, poliovirus, Giardia, Cryptosporidium, roundworms, pinworms, and tapeworms.
Which supplements are of most interest in immunity and infectious disease?
Micronutrient supplementation, specifically vitamin-a, vitamin-e, vitamin-d, folate, and zinc, particularly in the case of specific deficiency, is known to enhance immune infection and reduce susceptibility to different infections. Several herbs, such as garlic, ginger, turmeric, korean red ginseng, licorice, and ashwagandha have shown antiviral and other antimicrobial properties in preclinical studies. Very few have been systematically studied in human clinical studies.[2] In addition, duration, severity and susceptibility to the common-cold are all reduced by garlic supplementation.
Supplement Guide
Examine Database: Immunity & Infectious Disease
Research FeedRead all studies
In this randomized controlled trial, supplementation with heat-treated Lactiplantibacillus plantarum in participants with no known health conditions did not improve immune system health, compared to a placebo.
Frequently asked questions
Infectious diseases are human illnesses caused by microbial agents that can be transmitted from one person to another, either through direct contact or through the environment (e.g. infected air, water, food, objects, and surfaces). Some microbes are helpful and are required for normal bodily function, particularly in the gut. Others, under the right conditions, cause human illness. These illnesses range from benign conditions like folliculitis or skin infections, to long-standing and chronic infections (e.g., tuberculosis, leprosy, Lyme disease), to rapidly fatal illness (e.g., SARS, septic shock).
In general, immuno-compromised people are most at risk. This may be due to malnutrition, the extremes of age (infants, elderly), cancer (e.g. leukemia), chemotherapy, immunosuppression after organ transplantation, HIV-AIDS, congenital immunodeficiency syndromes, or unvaccinated status when effective vaccines are available.
Most infectious diseases are manageable with supportive care and the use of antimicrobial agents such as antibiotics, antivirals, antifungals, and antiparasitics. Sometimes it may be necessary to medically take over a failing organ system (e.g., ventilators during severe pneumonia, hemodialysis during renal failure from septic shock). Recovery, with or without disability, is often possible with such advanced supportive care. There are, however, pathogens that do not have definitive cures, meaning the pathogen can’t be fully eliminated from the body with a specific treatment. Examples include herpes simplex virus-1 (HSV-1, the typical cause of oral herpes), herpes simplex virus-2 (HSV-2, the typical cause of genital herpes), human immunodeficiency virus (HIV, the cause of AIDS), hepatitis B virus (HBV), polio, rabies, Ebola, Marburg virus, dengue, and an assortment of prion diseases including Kuru, fatal familial insomnia, and variant Creutzfeldt-Jakob disease (vCJD).
Malnutrition, the inadequate intake of calories and/or protein, is the most common cause of immunodeficiency, which increases the risk of contracting an infectious disease. Similarly, being deficient in certain micronutrients, especially vitamin-a, vitamin-e, vitamin-d, folate, and zinc, increases susceptibility to infections.[1] Consumption of raw, unwashed, inadequately cooked, or contaminated plant material, dairy, or meat is a common mode of acquiring infections from microbes like E. coli, Shigella, Salmonella, Listeria, Campylobacter, hepatitis A virus, norovirus, poliovirus, Giardia, Cryptosporidium, roundworms, pinworms, and tapeworms.
Micronutrient supplementation, specifically vitamin-a, vitamin-e, vitamin-d, folate, and zinc, particularly in the case of specific deficiency, is known to enhance immune infection and reduce susceptibility to different infections. Several herbs, such as garlic, ginger, turmeric, korean red ginseng, licorice, and ashwagandha have shown antiviral and other antimicrobial properties in preclinical studies. Very few have been systematically studied in human clinical studies.[2] In addition, duration, severity and susceptibility to the common-cold are all reduced by garlic supplementation.
References
- ^Katona P, Katona-Apte JThe interaction between nutrition and infection.Clin Infect Dis.(2008-May-15)
- ^Perera WPRT, Liyanage JA, Dissanayake KGC, Gunathilaka H, Weerakoon WMTDN, Wanigasekara DN, Fernando WSK, Rajapaksha RMH, Liyanage RP, Perera BTAntiviral Potential of Selected Medicinal Herbs and Their Isolated Natural Products.Biomed Res Int.(2021)