694

J Formos Med Assoc | 2010 • Vol 109 • No 10

Contents lists available at 

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Journal of the Formosan Medical Association

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http://www.jfma-online.com

J Formos Med Assoc 2010;109(10):694–701

Journal 

of the

 

Formosan Medical Association

ISSN 0929 6646

Formosan Medical Association
Taipei, Taiwan

Volume 109 Number 10 October 2010

New Delhi metallo-

b-lactamase-1

HTLV-1 and adult T-cell leukemia
Detection of nighttime melatonin level in Chinese original quiet sitting
Solifenacin and Tolterodine in the treatment of overactive bladder
 symptoms

Original Article

Detection of Nighttime Melatonin Level in Chinese
Original Quiet Sitting

Chien-Hui Liou,

1

Chang-Wei Hsieh,

2,3

Chao-Hsien Hsieh,

1,4

Der-Yow Chen,

1,5

Chi-Hong Wang,

6

Jyh-Horng Chen,

1†

* Si-Chen Lee

7

*

Background/Purpose: Some research has shown that melatonin levels increase after meditation practices,
but other research has shown that they do not. In our previous functional magnetic resonance imaging
study, we found positive activation of the pineal body during Chinese Original Quiet Sitting (COQS). To
find other supporting evidence for pineal activation, the aim of this study was to evaluate the effect of
COQS on nighttime melatonin levels.
Methods: Twenty subjects (11 women and 9 men, aged 29–64 years) who had regularly practiced daily med-
itation for 5–24 years participated in this study. All subjects served alternately as participants in the medi-
ation and control groups. COQS was adopted in this study. Tests were performed during two nighttime
sessions. Saliva was sampled at 0, 10, 20, 30, 45, 60 and 90 minutes after COQS and tested for level of melan-
tonin. Time period effect analysis and mixed effect model analysis were preceded by paired test analysis.
Results: In the meditation group (n

= 20), the mean level of melatonin was significantly higher than the base-

line level at various times post-meditation (p

< 0.001). Within the control group (= 20), the mean level of

melatonin at various times was not significantly different compared with baseline (p

> 0.05). These results

suggested that the melatonin level was statistically elevated in the meditation group and almost unchanged in
the control group after nighttime meditation. The urine serotonin levels detected by measuring 5-hydroxy-
indole-3-acetic acid levels were also studied, but no detectable difference between the groups was found.
Conclusion: Our results support the hypothesis that meditation might elevate the nighttime salivary
melatonin levels. It suggests that COQS can be used as a psychophysiological stimulus to increase endogenous
secretion of melatonin, which in turn, might contribute to an improved sense of well-being.

Key Words: meditation, melatonin, pineal body, saliva

©2010 Elsevier & Formosan Medical Association

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1

Interdisciplinary MRI/MRS Laboratory, 

7

Department of Electrical Engineering, 

5

Department of Psychology, and 

4

Neurobiology

and Cognitive Science Center, National Taiwan University, Taipei, 

2

Department of Photonic and Communication Engineering,

Asia University, Taichung County, 

3

Anthro-Celestial Research Institute, The Tienti Teachings, Nantou County; 

6

Department

of Neurology, Cardinal Tien Hospital Yung Ho Branch, Yung Ho City, Taipei County, Taiwan.

Received: July 17, 2009
Revised: October 18, 2009
Accepted: January 1, 2010

*Correspondence to: Professor Si-Chen Lee, Department of Electrical Engineering, National
Taiwan University, 1 Section 4, Roosevelt Road, Taipei 10617, Taiwan. 
E-mail: sclee@cc.ee.ntu.edu.tw
OR 
*Correspondence to: Professor Jyh-Horng Chen, Interdisciplinary MRI/MRS Laboratory,
Department of Electrical Engineering, National Taiwan University, 1 Section 4, Roosevelt
Road, Taipei 10617, Taiwan. 
E-mail: jhchen@ntu.edu.tw

Si-Chen Lee and Jyh-Horng Chen contributed equally to this work.

Meditation, melatonin and physiological effects

J Formos Med Assoc | 2010 • Vol 109 • No 10

695

Chinese Original Quiet Sitting (COQS) is a type of

traditional Chinese meditation. In ancient China,

meditation was the principal practice used by

Taoists to temper the spirit and body. In our pre-

vious functional magnetic resonance imaging

(fMRI) study, we found positive activation of the

pineal body during this meditation practice.

1

The

pineal body produces many substances, including

melatonin,

2

and melatonin levels during COQS

have never been studied, therefore, we hypothe-

sized that COQS might also cause an increase in

melatonin levels. Furthermore, there have been

many studies on the physiological effects of mel-

atonin. As has been reported, melatonin is effec-

tive in reducing cancer development or the risk

of cancer mortality.

3–5

It also has functional ef-

fects on cellular bioenergetics

6

and cellular re-

gulation.

7

In addition, it possesses antioxidant

effects,

8–10

anti-aging properties,

11

and locally re-

gulates human placental function.

12

Circadian

rhythm corresponds to the secretion of mela-

tonin.

13–17

Melatonin might also influence im-

mune function and seasonal fertility in some

animals.

18,19

The potential interaction between

COQS, pineal activation and melatonin levels

becomes more interesting and important due to

these special physical effects of melatonin.

In recent years, meditation has become an in-

creasingly popular form of exercise worldwide.

Some religious people practice meditation on a

daily basis to improve their body, mind and

spirit. There are many different styles of medita-

tion. However, the mechanism by which medita-

tion improves health remains unclear. Massion

et al tested the hypothesis that the regular prac-

tice of mindfulness meditation is associated with 

increased physiological levels of melatonin, and

have obtained some positive results.

20

Tooley et al

studied whether a period of meditation can in-

fluence melatonin levels. Transcendental Sidhi

and yoga meditation have also been studied and

their practice has been shown to result in signifi-

cantly higher plasma melatonin levels.

21

Harinath

et al evaluated the effects of Hatha yoga and

Omkar meditation on cardiorespiratory perform-

ance and melatonin secretion. They found that

plasma melatonin levels increase after 3 months

of yoga.

22

In contrast, Solberg et al studied mela-

tonin secretion during ACEM meditation (ACEM

is a meditation organization that originated in

Oslo, Norway), and although they have found that

advanced meditators have higher melatonin lev-

els than non-meditators, melatonin actually de-

creases during long-term meditation.

23

Carlson

et al investigated the benefits of a mindfulness-

based stress reduction meditation program for

early-stage breast and prostate cancer patients, and

have found no overall changes in melatonin lev-

els.

24

It appears that the secretion of melatonin

might depend on the style of meditation. There-

fore, it is necessary to determine whether night-

time salivary melatonin levels are elevated or

depressed after COQS.

Melatonin is synthesized endogenously from

the amino acid tryptophan (derived from 

serotonin) by the enzyme 5-hydroxyindole-O-

methyltransferase. Serotonin is a monoamine

neurotransmitter that is synthesized in seroton-

ergic neurons in the central nervous system and

enterochromaffin cells in the gastrointestinal tract.

Bujatti et al found a highly significant increase 

in 5-hydroxyindole-3-acetic acid (5-HIAA; the

main breakdown product of serotonin) in urine

after transcendental meditation.

25

In contrast,

Solberg et al found that serotonin concentrations

decreased in meditation and reference groups

after 1 hour of meditation (p

< 0.01).

23

These con-

trasting results need to be examined further. 

Urine serotonin levels detected by 5-HIAA were

measured in our study. The aim of this study was

to investigate the nighttime salivary melatonin 

levels after COQS.

Materials and Methods

Meditation style

The overall COQS process is separated into two

distinct parts: (1) several minutes of silent recita-

tion of specific religious mantra and mental imag-

ination of receiving spiritual energy (which is

named “Invitation of Primordial Qi”: IPQ); and

C.H. Liou, et al

696

J Formos Med Assoc | 2010 • Vol 109 • No 10

(2) a longer period of relaxation with no further

action of the mind and letting Qi do its work 

(referred to as “Allow its Natural Workings”:

ANW).

26,27

Chen et al studied COQS using elec-

troencephalography and have found a marked

increase in brain 

θ-waves and decreased α- and

β-waves.

28

We also carried out an fMRI study.

1

Nighttime salivary melatonin levels during this

meditation practice were measured.

Salivary melatonin analysis

A number of biological fluids can be sampled as

sources of melatonin, including saliva, serum,

plasma, urine, sweat and tissue extracts. The most

direct and convenient way to measure melatonin

levels is through saliva analysis. For subject com-

fort and to minimize influencing the levels dur-

ing sampling, we performed the saliva sampling

as described below.

Experimental design

The test periods chosen were at night. The overall

sampling period was set to 90 minutes, including

10 minutes of rest for subjects to calm down, 5

minutes of IPQ, 30 minutes of ANW, and then a

resting state of 45 minutes. The sampling points

were set at 0, 10, 20, 30, 45, 60 and 90 minutes

from the beginning of the experiment (23:00)

(Figure 1). The salivary samples of the meditation

group members were obtained by the control

group members or other helpers.

Subjects and regulations

Twenty subjects (11 women and 9 men) partici-

pated in the meditation and control groups. All

subjects were in good health; exclusion criteria

included epilepsy, psychosis, diseases of the nerv-

ous system, and a history of head trauma. Before

our meditation experiments, all subjects were first

asked to read the experimental instructions and

were given an explanation of the test. Each subject

filled out the “Subject Information and Agreement

form”. After each test, a short discussion was held

to allow us to collect information on each sub-

ject’s situation and conditions. The mean age 

of the subjects was 52.17

± 2.16 years [mean ±

standard error of the mean (SEM); range, 29–64

years], with meditation experience of 15.83

± 1.42

(5–24) years. They practiced meditation every

day, 2.03

± 0.16 (1–4) times, with a mean prac-

tice duration of 57.5

± 3.98 (30–90) minutes each

time. Their average bedtime was 23.58

± 0.14

(22.5–24.5) o’clock. Thirteen subjects were mem-

bers of religious groups (age, 29–63 years) and

lived in the Taoist Sanctuary. Seven subjects were

retired (age, 57–64 years). All subjects were 

well-trained meditators (Table 1).

Experiments were carried out over 2 days.

Different sleep/wake schedules might have dif-

ferent melatonin secretion profiles. Maintenance

of normal daily activities of every subject was taken

0

10

Resting

Resting

IPQ

ANW

20

30

45

Time (min)

60

90

Figure 1. The test periods adopted in the salivary mela-
tonin study of meditation practice. IPQ

= Invitation of

Primordial Qi; ANW

= Allow its Natural Workings.

Table 1.

Information on the subjects and self-
evaluation of the effect of saliva sampling
operation during the meditation process
(= 20)

Mean

± SEM (range)

What is your age?

52.17

± 2.16 (29–64)

How many years have 

15.83

± 1.42 (5–24)

you practiced meditation?

How many times do you 

2.03

± 0.16 (1–4)

practice every day?

How long do you practice 

57.50

± 3.98 (30–90)

each time? (min)

When do you go to bed 

23.58

± 0.14 (22.5–24.5)

each night? (o’clock)

Does the saliva sampling 

2.25

± 0.19 (1–5)

operation have any 

adverse effects on your 

meditation? (1–10 scale)*

*The scale numbers are set from 1 to 10, with a 1 meaning no 
effect at all and a 10 meaning a very seriously adverse effect.
Every subject was asked to give a score subjectively right at the
end of the experiment. SEM

Standard error mean.

Meditation, melatonin and physiological effects

J Formos Med Assoc | 2010 • Vol 109 • No 10

697

into consideration during the test to avoid diur-

nal changes in hormone levels, and to eliminate

misleading results from differences in subjects’

endogenous circadian phases. A proper period of

experiment was carefully chosen. As the average

bedtime of the subjects was around 23:35 hours,

all experimental procedures and apparatus were

prepared at 22:30 hours and performed between

23:00 and 00:30 hours. Furthermore, all subjects

participated in the meditation and control groups

during these 2 research days. Half of the subjects

who participated in the meditation group on the

first day were assigned to the control group on the

second day, and vice versa. Before the test, all sub-

jects were instructed to maintain their normal

daily activities, but not to meditate or eat in the 

3 hours before the experiment. Subjects were in-

structed to refrain from coffee, tea, and smoking

for at least 4 hours before the test, and to refrain

from alcohol and bananas for at least 24 hours

before the experiment. During the experimental

period, the meditation group was advised to stay

alert and not to fall asleep during this process.

The control group was advised to sit and rest in

the manner in which they preferred, but to avoid

talking, sleeping, or walking. Furthermore, when

the meditation group was in the IPQ stage, the con-

trol group was asked to recite one short poem

slowly. During the sampling period, there was no

verbal communication. Subjects refrained from eat-

ing and avoided beverages that contained artificial

colorants, as well as coffee or alcoholic beverages.

Light exposure control

All subjects were asked to reach the test room at

22:30 hours for preparation on the 2 experimen-

tal days. All subjects were in the same room; there-

fore, the light exposure of each individual subject

was controlled at the same level on these two ex-

perimental nights. During the period 22:50–23:00

hours, all subjects sat in the test room and verbal

communication was allowed with the light on.

The light was switched off in the test room at ex-

actly 23:00 hours and remained off until the end

of the experiment, which allowed only the light of

the corridor to pass through the windows. The first

10 minutes was a rest period for subjects to enable

them to calm down. No verbal communication

was allowed. The subsequent periods were COQS-

IPQ for 5 minutes, COQS-ANW for 30 minutes,

and 45 minutes for further rest. Light intensity

was carefully controlled and maintained at the

same level during these two dates. Light levels

were monitored throughout the experiment and

did not exceed 5 lux.

Sampling and data analysis

To test whether post-meditation melatonin lev-

els differed from baseline levels, saliva samples

were obtained using saliva collection tubes

(Salivette, Sarstedt Inc., Rommelsdorf, Germany)

and analyzed with competitive enzyme-linked

immunoassay (Direct Saliva Melatonin ELISA

kit; Buhlmann Laboratories, Schonenbuch,

Switzerland). Results were analyzed using CODA

Automated EIA Analyzer (Bio-Rad, Hercules, USA).

The means and SEM of each value of the sampling

data were first calculated. As a result of the re-

peated measurement design of our study, within-

subject data were assumed to be correlated. To

test the time period effect, a paired test was per-

formed to compare the mean difference between

various time points [Post I: 10

≤ 45 min (with 3

time points); Post: 10

≤ 90 min (5 time points);

Post II: 45

≤ 90 min (2 time points)] and the

baseline [Pre: 0

≤ ≤ 10 min (2 time points); the

average of data on 0 and 10 min] by treatment.

One-sided analysis of variance was used for hy-

pothesis testing for the treatment and time effects,

and the values reported were one-sided.

Urine serotonin analysis

The main breakdown product of serotonin, 5-

HIAA, was analyzed in the urine samples of the

20 subjects. Each subject collected the urine in a

1.5-L bottle with 3 mL 6 N HCl within 6 hours of

the experiment on their mediation and control

dates. Samples were stored in a cold chamber kept

at 

< 5°C before being analyzed. The analytical

instrument adopted was the high-performance

liquid chromatography, which contained the sol-

vent and sample manager, column chamber and

C.H. Liou, et al

698

J Formos Med Assoc | 2010 • Vol 109 • No 10

detector. The concentrations of the sample con-

stituents were identified and quantified. Analytical

results of raw data and chromatography were

also obtained. Means and SEM of the data were

calculated as the final results.

Results

Subject self-evaluation

All subjects were asked to perform a self-evaluation

task after the experiments to ascertain whether

the saliva sampling operation had adverse effects

on their meditation. The scale numbers were set

from 1 to 10, with 1 meaning no effect and 10

meaning a very strong effect. Every subject was

asked to give a score immediately after the end of

the experiment. Although these scores might have

been arbitrary or subjective, they did provide cer-

tain information on what happened among the

subjects during the sampling operation. The

mean self-evaluation score was 2.25

± 0.19 (range,

1–5; Table 1), which suggested that the saliva

sampling operation had a slight effect on the sub-

jects  during the meditation process. Most sub-

jects claimed that they were immediately able to

return to the good and positive meditating situa-

tion after each saliva sampling operation.

Salivary melatonin analysis

Upon processing the data from the melatonin ana-

lysis, we first dealt with the baseline homogeneity

analysis. The baseline values (average of data at 

0 and 10 min) in the meditation/control treat-

ment were 8.37

± 2.13/5.65 ± 1.11, and the mean

baseline difference between meditation and con-

trol treatment was 2.72, with a paired test  p

value of 0.060, and the 95% confidence interval of

–0.12 to 5.56. We also applied a time point effect

analysis. Within the mediation treatment group,

the mean level of melatonin at various post-

meditation time points (Post I: 9.42

± 2.44 pg/mL;

Post: 9.93

± 2.39 pg/mL; Post II: 10.70 ± 2.42 pg/

mL) was significantly higher than baseline levels

(Pre: 8.37

± 2.13 pg/mL), with < 0.05 for “Post I”

and p

< 0.001 for both “Post” and “Post II” peri-

ods. However, within the control treatment group,

the mean level of melatonin at various post time

points (Post I: 6.51

± 1.50 pg/mL; Post: 6.70 ±

1.48 pg/mL; Post II: 6.97

± 1.48 pg/mL) was not

significant (p

> 0.05) in comparison to baseline

levels (Pre: 5.65

±1.11pg/mL) (Table 2). The results

suggested that the melatonin level was signifi-

cantly elevated after meditation in the medita-

tion group and almost unchanged in the control

group. Figure 2 shows the results of analysis of

melatonin levels of the meditation group and the

control group. The values of the meditation and

control groups between “Pre” and “Post I”, “Post”,

“Post II” are also shown.

Analysis of urine serotonin

The serotonin levels (urine 5-HIAA) of the medi-

tation and control groups for the 20 subjects were

Table 2.

Results of the time point effect analysis on melatonin levels

Paired test

Treatment

Time period*

Mean

SEM

One-sided p

95% CI

Meditation

Pre

8.37

2.13

Post I

9.42

2.44

0.043

(0.05, 

∝)

Post

9.93

2.39

< 0.001

(0.86, 

∝)

Post II

10.70

2.42

< 0.001

(1.26, 

∝)

Control

Pre

5.65

1.11

Post I

6.51

1.50

0.152

(

−0.55, ∝)

Post

6.70

1.48

0.106

(

−0.35, ∝)

Post II

6.97

1.48

0.064

(

−0.12, ∝)

* Pre: 0

≤ ≤ 10 min; Post I: 10

<

t

≤ 45 min; Post: 10

<

t

≤ 90 min; Post II: 45

<

t

≤ 90 min. SEM

=

Standard Error of the Mean; CI

=

confidence interval.

Meditation, melatonin and physiological effects

J Formos Med Assoc | 2010 • Vol 109 • No 10

699

analyzed (Table 3). The results showed no statisti-

cal difference (p

= 0.22) between the 5-HIAA levels

in the meditation group (0.86

± 0.10 mg/6 hr)

and the control group (0.96

± 0.15 mg/6 hr).

Discussion

During the experimental process, we carefully

controlled the timing and light exposure and

each subject participated in the meditation and

control groups. Thus any misleading and negative

effect due to light-induced suppression and dif-

ferences in individual circadian cycles should

have been reduced. Our results exhibited statisti-

cal significance (with p

< 0.05 for Post I and

p

< 0.001 for Post and Post II periods) and sup-

port the hypothesis that COQS can elevate night-

time melatonin levels. These results also support

our previous fMRI observation of pineal activation

during COQS.

1

All the information suggests that

COQS, pineal activation and melatonin levels

have a positive interaction, which implies that

COQS activates the pineal body and results in

nighttime secretion of melatonin. Massion et al,

20

Tooley et al

21

and Harinath et al

22

also found ele-

vation of nighttime melatonin levels. Massion et al

measured urine melatonin, whereas Tooley et al

and Harinath et al measured plasma melatonin.

In our study, although the variation in salivary

melatonin levels was not as sensitive as in plasma,

salivary melatonin was still significantly increased

in COQS for well-trained meditators. As the

nighttime melatonin levels are elevated, medita-

tion might influence the effects of melatonin;

these include cancer prevention,

3–5

influencing

cellular bioenergetics functions

6

and cellular reg-

ulation,

7

antioxidant effects,

8–10

anti-aging prop-

erties,

11

regulation of human placental function,

12

circadian rhythm,

13–17

immune function

18,19

and

any other function that might relate to melatonin.

Revell et al published melatonin daily profiles

from their research of circadian phase determina-

tion.

29

From these profiles, we see that the daily

melatonin levels are higher at midnight and lower

in the daytime. As we have already mentioned,

Solberg studied melatonin secretion during the

meditation process and found that melatonin is

decreased after long meditation.

23

Perhaps this

discrepancy is due to the fact that they set the ex-

perimental period in the daytime (starting from

09:00 hours and lasting for 3 hours). The results of

samples taken during in a 3-hour daytime medi-

ation period might also need to be clarified. The

ultimate explanation of the decline in melatonin

levels, whether temporal or sampling, needs fur-

ther investigation. Carlson et al investigated a

mindfulness-based stress reduction meditation

program for early-stage breast and prostate cancer

patients, and found no overall changes in mela-

tonin.

24

It is possible that the following two rea-

sons explain their findings: (1) the daytime

(14:00 hours) samples used in the melatonin

assay could have led to insignificant change; and

(2) their subjects were patients who attended a

short meditation training course (8 weeks), and

the duration of training could have been insuffi-

cient. The combined effect of these two or other

0

Meditation

Melatonin level (pg/mL)

Control

2

4

6

8

10

12

< 0.05

p

= 0.15

p

= 0.11

p

= 0.064

< 0.001

< 0.001

14

16

18

20

Pre

Post I

Post

Post II

Figure 2. Analysis of melatonin levels in the meditation
and control groups. The time periods were Pre: 0

≤ ≤ 10

minutes; Post I: 10

≤ 45 minutes; Post: 10 < ≤ 90 min-

utes; Post II: 45

≤ 90 minutes. Error bars represent stan-

dard error of the mean.

Table 3.

Serotonin level in different groups*

Outcome

Meditation Control 

p

group

group

Serotonin 0.86

± 0.10

0.96

± 0.15

0.22

(mg/6 hr)

*Data presented as mean

± standard error mean; 

urine sero-

tonin levels were analyzed using the samples of the 20 subjects.
Each subject collected all urine from the onset point until 6 hours
later, on both their mediation and control experiment days.

C.H. Liou, et al

700

J Formos Med Assoc | 2010 • Vol 109 • No 10

reasons might have produced the similarities be-

tween the control and test groups. Further testing

of these hypotheses is now required. 

We also dealt with the mixed effect model

analysis. The results showed that the main effect of

treatment/time was not significant [F(1,171)

=

1.09,  p

= 0.300/F(4,171) = 1.41, = 0.233]. The in-

teraction between treatment and time was also

not significant [F(4,171)

= 0.29, = 0.883]. All 20

subjects participated in the meditation and con-

trol groups, therefore, the “self-anticipating effect”

of the meditators (during the “Pre” state and wait-

ing for the meditation period) and the “regulated

routine effect” (the daily course and custom of a

well-trained meditator to participate in the control

group) might have played a role in our results.

Neither of these effects is believed to have led to

the significant difference between the meditation

and control groups.

In this study, we examined the influence of

COQS on nighttime salivary melatonin levels. Our

results suggest that nighttime melatonin level was

significantly elevated for the meditation group but

almost unchanged for the control group. This sup-

ports the hypothesis that this meditation practice

could elevate nighttime melatonin levels. These

results also support our previous fMRI observation

of positive activation of the pineal body during

meditation practices. All the information obtained

implies that meditation causes activation of the

pineal body, which results in secretion of night-

time melatonin, and which might also have cer-

tain physiological effects on the human body.

Further studies could be needed to establish the

circadian phase as a baseline for each individual,

and to determine more conclusively detailed

melatonin secretion profiles and daytime mela-

tonin levels under the influence of COQS.

Acknowledgments

Thanks are due to the Tienti Teachings for intro-

ducing us to the subjects. We also thank Dr Min-

Long Lai (Union Clinical Laboratory, Taipei,

Taiwan) for his analytic assistance with the 

sampling of melatonin and serotonin. In addition, 

we would like to thank Professor Jen-Pei Liu and

Dr Tzu-Chi Lee (Consulting Center for Statistics

and Bioinformatics, National Taiwan University,

Taipei, Taiwan) for their statistical analysis of the

experimental data.

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