Treatment of Anosmia and Ageusia in COVID-19
Patients by Using Coffee
Asiyeh Hosseini ( firstname.lastname@example.org )
responsible of rural health services of Dehkool
Professor Mechanic Eng. Technical University of Golpayegan
Mina Akbari Moghadam
responsible of rural-urban health services of Zahak
Keywords: Anosmia, Ageusia, Coffee, COVID-19
License: This work is licensed under a Creative Commons Attribution 4.0 International License.
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Introduction: The sudden onset of smell and taste loss has been reported as a symptom related to COVID-
19. There is new evidence for the loss of smell and taste as a symptom of COVID-19 infection.
Objectives: This study aims to examine inuence of coffee on smell and taste of patients with Covid-19.
Methods: In order to investigate the effect of coffee consumption on the taste and smell of COVID-19
patients, we attempted to sample in 20 provinces of the country, COVID-19 patients were separated by
gender and underlying and non-underlying disease, doses of 15-20 mg for non-underlying patients and
25-30 mg for underlying patients. The reason for determining this amount of coffee is that every coffee
we want to prepare needs a scoop of 14 grams of coffee, which we determine. For some people, it was
determine 14 grams and for some people 28 grams of coffee was determined due to consumed in two
cups of coffee.
Results: Patients with Covid-19 had reversibility on the rst and second day. It was clear that there is a
small gap between the proportion of recovered patients in the underlying and non-underlying patients, but
due to the high volume of observations, this small difference is evident.
Conclusions: Anosmia and Ageusia is more prevalent in COVID-19 patients. Caffeine in coffee reduced
the reversibility of the sense of smell and taste of people with Covid-19. It was concluded that the
chances of recovery are higher for those who do not have the underlying disease than for the other
groups and for those who suffer from all three types of the underlying disease than for the other groups.
In December 2019, Coronavirus Disease 2019 (COVID-19) outbreak occurred in Wuhan, Hubei Province,
China and spread rapidly throughout China, and then emerged around the world [1-3]. On February 12,
2020, WHO named the disease caused by the novel coronavirus as COVID-19 . Clinical evidence has
shown that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can be transmitted by person-
to-person .Since the outbreak of the COVID-19 pandemic, observations and scientic reports have been
accumulating rapidly that sudden anosmia and taste disorders are symptoms associated with the COVID-
19 infection [5-6]. Recently the World Health Organization has included the loss of smell or taste as a new
symptom of COVID-19 infection as have many Health Authorities after a surge of publications and press
releases that pointed to anosmia as a potential screening symptom that might contribute to the decision
to test suspected cases or guide quarantine instructions. COVID-19 has also been having a major impact
on health due to its higher degree of transmissibility, leading to a rapid worldwide dispersion . The
main symptoms identied so far are: fever, cough, fatigue, myalgia, arthralgia and dyspnea, which can
result in respiratory failure . Non-respiratory symptoms such as palpitations, abdominal pain, diarrhea,
headache and dizziness may precede respiratory symptoms, or come in isolation . It is known that the
virus has as target cells that express receptors of the Angiotensin 2 Converting Enzyme (ACE2). ACE2
receptors are expressed predominantly by epithelial cells of the lung, intestine, kidney, heart and blood
vessels, the former being the main organ affected by SARS-CoV-2 . However, this does not seem to be
the only route of virus entry into the cells, since the liver is quite affected although it doesn’t have many
ACE2 receptors . The human brain also shows itself as a site with expression of ACE2 receptors,
which seems to justify the neurotropism of SARS-COV-2 by the Central Nervous System (CNS). Studies
corroborate the hypothesis of tropism of the coronavirus by the olfactory neuroepithelium and of
neurological manifestations in conrmed cases of the disease [12-13]. The increase in cases of sudden
loss of the sense of smell (SLoS) noted in medical care during the COVID-19 pandemic motivated the
present study. The physiological importance of olfaction in identifying environmental factors and
potential threats is so important that the loss of the olfactory sense is related to a reduction in life
expectancy, even in individuals without diagnosis of neurodegenerative disease such as Alzheimer’s or
Parkinson’s disease . Olfactory disorder is a problem already described in most of the countries
affected by COVID-19 .
In the absence of any comprehensive analysis of the subject, we reviewed the published literature on
COVID-19 associated early dysgeusia and anosmia, nding a total of ve studies from the European
community, China, Italy, USA, and Iran. These yielded a total of 10,847 COVID-19 patients; 8,816 (81.27%),
and 8,119 (74.85%) presented with/developed dysgeusia and/or anosmia, respectively indicating these
symptoms in almost three-quarters of COVID-19 patients. In developing countries like Brazil, COVID-19
testing is restricted to a small portion of patients due to the lack of availability of tests for the entire
population. Thus, mild and even moderate cases are not being reported through positive laboratory
evidence [5-13]. However, there are knowledge gaps.
The objective of this systematic review was to examine effect of coffee on Anosmia and Ageusia in
COVID-19 Patients. The main reason for choosing coffee as a laboratory material in the present study is
that due to its caffeine content, coffee can affect the sense of smell and taste of COVID-19 patients. But
substances such as caffeinated beverages have not been selected because they can be harmful to
people with diabetes.
It takes at least 30 to 45 days for reversibility of the sense of smell and taste. In the present study,
according to experiments, caffeine of coffee in different groups has had signicant effects. In order to
investigate the effect of coffee consumption on the taste and smell of COVID-19 patients, we attempted
to sample in 20 provinces of the country, COVID-19 patients were separated by gender and underlying and
non-underlying disease, doses of 15-20 mg for non-underlying patients and 25-30 mg for underlying
patients. In this study, eld patients are divided into the following 4 groups: (1) Diabetes and
hypertension; (2) Heart disease and hypertension; (3) Heart disease and diabetes; Heart disease,
hypertension and diabetes. The Consort ow deagram is also shown in gure 1.
Finally, it was investigated the issue of patients' recovery or non-recovery according to their recovery time
and the results were recorded. In the following, it will examine the observations in descriptive statistics
and inferential statistics. To describe the observations, rst, we plotted the bar graphs of the number of
recovered and non-recovered people by those who consumed coffee and those who did not consume
coffee (Fig. 2).
Figure 2 indicated that how coffee consumption have inuence on improving people. However, in order to
provide a further distinction, in reporting the number of recoveries, it was also used the type of underlying
and without underlying disease (Fig. 3). Again, like gure 2, we observed that how much coffee
consumption plays a role in improving people. Also, people without non-underlying diseases are more
common than other people.
Diabetes and hypertension are also the most common underlying diseases. Among them, patients that
have been affected by all three types of underlying diseases have the lowest frequency. In order to make
better use of the information in these graphs, in the following table, it was extracted the total number of
patients and the proportion of recoveries for people who drank coffee separately into groups of
underlying and without underlying patients.
Tabl e 1. The total numbe r of patients and the proportion of recovere d patients by underl ying are for peo ple who have consumed
with coffee without coffee
disease diabetics and blood pressure improvement improved 98.3% 1.3%
not improved 1.7% 98.7%
heart and diabetic and hypertension improvement improved 96.6% 1.4%
not improved 3.4% 98.6%
heart and diabetics improvement improved 98.2% 1.1%
not improved 1.8% 98.9%
heart and hypertensive improvement improved 98.4% 1.2%
not improved 1.6% 98.8%
without underlying disease improvement improved 98.5% 1.3%
not improved 1.5% 98.7%
The smallest rate of recovery is 0.966 and is related to patients who have all three underlying diseases;
also the highest rate is related to people who do not have underlying diseases. The ratio of those who
have not consumed coffee is equal to 0.014 and is related to people who have all three underlying
diseases. In the rst step, we examined the effectiveness of coffee consumption in improving the sense
of smell and taste by group of underlying and without underlying patients. The ndings are shown in
Table 2. It should be noted that we examined the gender factor separately in all of the following
Tabl e 2. Chi-Square tests to evalua te the effectivenes s of coffee consumpti on in improving patie nts' sens e of smell and taste by
group of underl ying and without underlying patients
disease Value df Asymptotic Significance
Exact Sig. (2-
diabetics and blood pressure Pearson Chi-Square 19084.878 1 0.000 0.000
Continuity Correction 19079.239 1 0.000
Likelihood Ratio 18736.814 1 0.000 0.000
Fisher's Exact Test 0.000
19083.969 1 0.000 0.000
heart and diabetic and
Pearson Chi-Square 10598.242 1 0.000 0.000
Continuity Correction 10594.050 1 0.000
Likelihood Ratio 12546.883 1 0.000 0.000
Fisher's Exact Test 0.000
10597.359 1 0.000 0.000
heart and diabetics Pearson Chi-Square 16105.838 1 0.000 0.000
Continuity Correction 16101.002 1 0.000
Likelihood Ratio 17781.581 1 0.000 0.000
Fisher's Exact Test 0.000
16104.918 1 0.000 0.000
heart and hypertensive Pearson Chi-Square 16925.430 1 0.000 0.000
Continuity Correction 16920.561 1 0.000
Likelihood Ratio 18663.076 1 0.000 0.000
Fisher's Exact Test 0.000
16924.505 1 0.000 0.000
without underlying disease Pearson Chi-Square 43600.864 1 0.000 0.000
Continuity Correction 43592.902 1 0.000
Likelihood Ratio 32887.105 1 0.000 0.000
Fisher's Exact Test 0.000
43599.984 1 0.000 0.000
Total Pearson Chi-Square 107006.670 1 0.000 0.000
Continuity Correction 107000.978 1 0.000
Likelihood Ratio 104083.050 1 0.000 0.000
Fisher's Exact Test 0.000
107005.766 1 0.000 0.000
In Table 2, it uses chi-squared tests such as Pearson Chi-Square, Likelihood Ratio, Fisher's Exact Test, and
Linear-by-Linear Association for contingency tables. By using two columns on the right that show
signicance, the initial assumption can be judged. It has been calculated signicant values in these two
columns by using two methods of asymptote and Monte Carlo. Here, we observed that the signicance is
equal to 0.000 in all cases. Therefore, for all test methods, in all groups of underlying and non-underlying
patients, we reject the initial assumption at the level of α = 0.01 and we accept the alternative assumption
based on the effectiveness of coffee consumption in improving patients.
The last line of this table was marked by Total, it examines the positive effect of coffee consumption on
the recovery of patients, regardless of whether the patient is a underlying and non-underlying. In this line,
we also observed the effectiveness of coffee consumption in improving patients.
We also examined whether underlying and non-underlying disease are effective in the recovery of
individuals or not, for this reason, it was extracted Table 3. In this Table, we observed that the type of
underlying disease is effective in improving patients. Although in Table 1, there is a small gap between
the proportion of recovered patients in the underlying and non-underlying patients, but due to the high
volume of observations, this small difference is evident. Carefully in Table 1, we nd that the chances of
recovery are higher for those who do not have the underlying disease than for the other groups and for
those who suffer from all three types of the underlying disease than for the other groups.
Tabl e 3. Chi-Square tests to evalua te the effect of underl ying and non-underlying disea se type on improvi ng patients' se nse of smel l
and tas te
Value df Asymptotic Significance (2-sided)
Pearson Chi-Square 3589.678 4 0.000
Likelihood Ratio 3589.482 4 0.000
Linear-by-Linear Association 1388.499 1 0.000
N of Valid Cases 118341
In the treatment of people with COVID-19, the last step that is reversible is the sense of smell and taste.
These patients tend to get a sense of taste and smell as soon as possible. The results of the present
experiment indicated that caffeine in coffee reduced the reversibility of the sense of smell and taste of
people with COVID-19. The smallest rate of recovery is 0.966 and is related to patients who have all three
underlying diseases; also the highest rate is related to people who do not have underlying diseases. The
ratio of those who have not consumed coffee is equal to 0.014 and is related to people who have all three
underlying diseases. Also, we concluded that the alternative assumption based on the effectiveness of
coffee consumption in improving patients. We also observed the effectiveness of coffee consumption in
improving patients. There is a small gap between the proportion of recovered patients in the underlying
and non-underlying patients, but due to the high volume of observations, this small difference is evident.
So, we understood that the chances of recovery are higher for those who do not have the underlying
disease than for the other groups and for those who suffer from all three types of the underlying disease
than for the other groups.
One of the limitations of this study is that it had not tendency to participate a group of older patients. It
was also dicult for them to accept that their sense of smell and taste was recovered by consuming
coffee, which they achieved after consuming this important event. Finding patients with an underlying
disease was dicult in months of effort. Spending a lot of time consuming coffee and training it to
prepare and type of consumption at some ages, which were generally over the age of 45, made the article
more time-consuming and lengthy.
Ethics approval and consent to participate
Ethics committee approval for a case report was considered. The patient gave her written informed
consent to the medical procedures used for treatment purposes
Conicts of interest
The authors declare no conicts of interest.
This study was conducted by a team of four people who came together to develop anticancer devices
before the outbreak of coronary heart disease. They were building this device initially by ultrasound
waves under the supervision of Eng. Mr. Mirmehdi. But after outbreak of this disease, their goal and
attention was concentrated on how to this disease. The authors would like to thank all Iranian health
workers, Eng. Mr. Mehdi Zarei, Ph.D. student of natural resources in American Michigan University, for the
efforts and sacrices they are making during this serious health crisis. Also, authors wish to thank
patients for their participation and kind cooperation.
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