The purpose of this study was to determine whether the consumption of tea, coffee, or both is associated with less frequent nasal carriage of methicillin-resistant Antibacterial properties of tea and coffee aureus MRSA. Our findings raise the possibility of a promising new method to decrease MRSA nasal carriage that is safe, inexpensive, and easily accessible. In an effort to both prevent and treat MRSA, researchers have examined the antimicrobial effects of several commonly consumed plants and plant extracts.
The purpose of this study was to evaluate the relationship between oral consumption of tea and coffee, and MRSA nasal carriage in a nationally representative sample of Americans. To enable these estimates, the survey uses sampling weights that are calculated by taking into account the unequal probabilities of selection resulting from sample design, nonresponse, and planned oversampling of minorities.
Stage 1 entails selection of primary sampling units PSUswhich are mostly single counties or, in a few cases, groups of contiguous counties with probability proportional to a measure of size. In stage 2, the PSUs are divided into segments generally city blocks or their equivalent. In stage 3, households within each segment are listed and a sample is randomly drawn.
In geographic areas where the proportion of age, ethnic, or income groups selected for oversampling is high, the probability of selection for those groups is greater than in other areas. In stage 4, individuals are chosen to participate in NHANES from a list of all persons residing in selected households. Each individual is assigned a sample weight, a measure of the number of people in the population represented by that individual in NHANES, reflecting the cocaine and cancer lymphoma probability of selection, adjustment for nonresponse, and adjustment to individual population controls.
More information on the methods of the — NHANES survey, including laboratory assessments, can be found elsewhere. Consequently, we included in our study only participants aged 2 years old or older. Nasal cultures were collected and plated on mannitol salt agar MSA. The antibacterial properties of tea and coffee were reexamined the next day, and any yellow or gold colonies were subcultured to BAPs.
A tube coagulase test using rabbit plasma with EDTA was then performed both on Staphaurex-negative isolates from BAPs with morphology consistent with S aureus and on Staphaurex-positive isolates with morphology inconsistent with S aureus. Staphaurex-positive isolates and Staphaurex-negative, tube coagulase—positive isolates were identified as S aureus and saved for further testing, antibacterial properties of tea and coffee.
S aureus isolates were screened for methicillin resistance by the disk diffusion method. For the purposes of this study, S aureus isolates with a zone diameter of 10 mm or less were considered MRSA and all other Staphylococcus isolates were considered methicillin sensitive MSSA.
Beverages evaluated were hot tea, iced tea, coffee, soda consumed during the summer, and soda consumed during the remainder of the year as ascertained with 6 questions. We evaluated numerous variables previously associated with MRSA nasal carriage as potential confounding variables in the relationship between MRSA carriage and beverage consumption.
They included age, race, sex, poverty status, health status, recent hospital stay, and recent antibiotic use. Poverty status was determined using the poverty-income ratio. Poverty-income ratios ranged up to 5, with values of less than 1 indicating poverty. Current health status was based on self-report and was classified as either 1 excellent, very good, or good, or 2 fair or poor. Do not include an overnight stay in the emergency room.
Participants were asked to bring the containers for all the prescription medications taken during the past month and to report combining lexapro and st johns wort medications taken for which the container was not available, antibacterial properties of tea and coffee.
These medications were then matched by trained survey interviewers to an annually updated comprehensive database of all prescription drugs in the US market. For the purposes of this analysis, we excluded individuals who were missing data on any variable. A total of 3, individuals were missing data. Of these individuals, the majority were missing data on coffee consumption arthritis and natural treatments,tea consumption 2, or poverty-income ratio antibacterial properties of tea and coffee The analyses incorporated both the stratification antibacterial properties of tea and coffee clustering aspects of the sampling design.
The proper weighting procedures include adjustments for basic probability of selection and nonresponse. Because minorities were oversampled, and the sampling design was complex, we used sampling weights provided by the NHANES to compute population estimates based on weighted parameter estimates and standard errors. We computed descriptive statistics for the study sample.
In addition to hot tea and coffee, iced tea and soft drink consumption were eyelid and mouth skin allergies to determine if the antimicrobial properties of hot tea and coffee differed from that of other types of beverages.
The sample included 5, individuals, which is equivalent to a weighted sample size of , The findings were similar for combined coffee and tea intake. Because fewer children than adults consume coffee and tea, we conducted a separate analysis to examine the association between coffee and tea consumption and MRSA nasal carriage among individuals aged 18 years or older. The results of this study suggest a lower likelihood of MRSA nasal carriage among individuals who drink hot tea, coffee, or both.
These findings, based on a nationally representative sample of adults and children in the United States, extend the previous findings of in vitro and topical antimicrobial activity of tea and coffee to a systemic effect. The mechanism behind this possible effect of coffee and tea consumption on Chinese lantern and asthma carriage is not completely understood. There is increasing evidence to suggest that both coffee and tea have antimicrobial characteristics.
In the case of coffee, particular attention has focused on the potential antibacterial properties of trigonelline, glyoxal, methylglyoxal, and diacetyl.
Although most of the data on the antimicrobial properties of coffee and hot tea have come from in vitro experiments, a few clinical trials have examined the effect of hot tea and coffee in vivo. In one study conducted by Fujii et al, 9 bedridden patients with MRSA-infected decubitus ulcers underwent debridement of their ulcers with either green tea or normal saline.
After 1 month, antibacterial properties of tea and coffee, the patients whose ulcers were treated with green tea debridement experienced a marked decrease in ulcer severity, and MRSA had disappeared in one-half.
In the patients treated with normal saline debridement, ulcer severity was unchanged, antibacterial properties of tea and coffee, and all of the ulcers were still infected with MRSA. In another study, 24 elderly patients with cerebrovascular disease and MRSA-positive sputum were randomized and treated with either tea catechin extracts or saline as a control, each given by a nebulizer 3 times daily, for 4 weeks.
Perhaps even more impressive, the average length of hospitalization was 51 days in the tea-treated group vs 85 days in the saline-treated group.
Our findings reinforce and expand the findings of earlier ex and risk of cancer by suggesting that tea has antibacterial properties not only when applied topically, but also when consumed orally.
What remains less clear is why iced tea did not affect the risk of nasal MRSA carriage in the same manner as hot tea. One possible explanation is that iced tea has lower levels than hot tea of polyphenolic compounds per unit volume, because many of the compounds in tea are more soluble at higher temperatures. Like iced tea, soda consumption did not antibacterial properties of tea and coffee the risk of MRSA nasal carriage.
As many sodas are caffeinated, this finding suggests that caffeine is unlikely to be responsible for the antibacterial properties of hot tea and coffee. Several important limitations to this study should be noted. Second, we excluded individuals from the study with missing values rather than using multiple imputation, which may have increased our standard error. Third, we could not be certain when individuals last consumed coffee or tea, antibacterial properties of tea and coffee.
Finally, because an exact understanding about the biochemical constituents in hot tea and coffee that may be associated with protection against MRSA remains to be elucidated, we had to speculate on a primary theory and several alternative theories. The effect, however, appears to be robust. Although not a specific limitation, it is important to note that the larger question of the importance of MRSA nasal carriage has yet to be resolved.
Even though several studies have suggested such carriage increases the risk of systemic infection with MRSA, others have not. At present, the only way to treat MRSA nasal carriage is with antibiotics that have proven only partially successful at long-term eradication.
Our findings of reduced odds of MRSA nasal carriage among tea and coffee drinkers raise the possibility of a promising new alternative to antibiotics that is safe, inexpensive, and easily accessible. National Center for Biotechnology InformationU. Journal List Ann Fam Med v. EverettPhD, and Dana E. KingMD, MS. This article has been cited by other articles in PMC. Methicillin-resistant Staphylococcus aureus, MRSA, tea, coffee, disease prevention, carriers, disease reservoirs, colonization.
Determination of Methicillin Resistance S aureus isolates were screened for methicillin resistance by the disk diffusion method. Beverage Consumption Beverages evaluated were hot tea, iced tea, coffee, soda consumed during the summer, and soda consumed during the remainder of the year as ascertained with 6 questions.
Control Variables We evaluated numerous variables previously associated with MRSA nasal carriage as potential confounding variables in the relationship between MRSA carriage and beverage consumption. Missing Data For the purposes of this analysis, we excluded individuals who were missing data on any variable.
Open in a separate window. Notes Conflicts of interest: Hospitalizations and deaths caused by methicillin-resistant Staphylococcus aureusUnited States, — Safdar N, Bradley EA. The risk of infection after nasal colonization with Staphylococcus aureus. Staphylococcus aureus nasal colonization and subsequent infection in intensive care unit patients: Infect Control Hosp Epidemiol. Methicillin-resistant Staphylococcus aureus nasal colonization is a poor predictor of intensive care unit-acquired methicillin-resistant Staphylococcus aureus infections requiring antibiotic treatment.
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