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Have Japanese People Become Asexual?
Love in Japan
JUN KOBAYASHI
Abstract: This article examines changing romantic relationships in contempo-
rary Japanese society. It specifically investigates whether Japanese people in
their twenties and thirties have become asexual; that is, whether they tend to
have few sexual experiences or interests. Data were collected through an inter-
net survey; this article uses a subsample of 9,940 respondents. The dependent
variables were the number of lovers respondents had during and after junior
high school; the independent variable was the respondents’age. Regression
analyses found a clear trend toward asexual behavior among young men
(in their twenties and thirties). However, young women are not as asexual as
the previous generation. This asexualization of men may have contributed to
Japan’s sharply declining marriage and birth rates. If so, other Asian societies
may learn lessons from Japan’s experiences in the future.
Keywords: love, asexual, Japan
Introduction
The Puzzle
According to the National Fertility Survey
of Japan, as of 2015, 87.7% of Japanese who
married did so based on a romantic relation-
ship, whereas only 5.5% participated in
arranged marriages (Fig. 1). Until the 1960s,
most Japanese young people had marriages
arranged by their parents. From the 1970s to
the present, marriage based on love has
been the dominant pattern. Consequently,
having a romantic relationship has virtually
become a prerequisite for getting married.
During the same period, according to
Japanese census data, people have become
much less likely to get married. In the
1930s, more than 98% of all Japanese
adults were married. By 2015, the percent-
age of adults who had never married had
risen to 24.2% for men and 14.9% for
women (Fig. 2).
Why are men more likely to remain
unmarried than women? Japan still permits
only heterosexual marriage, so it would
seem that the marriage rates of men and
women should be similar. But the data indi-
cate a difference of 10%.
Yamada and Shirakawa (2008) indicate
that men have become passive in roman-
tic relationships, tending to lose interest
in dating, pair bonding and sexual activ-
ity. As a result, they are sometimes even
hesitant to seek lovers. Morioka (2008)
called those young men “herbivores”
(soushokukei) in contrast to “carnivores”
(nikushokukei).
These trends can be described as a social
pattern of becoming asexual. The concept
of asexuality has been described by Poston
and Baumle (2010) as “lack”of sexual
experience or interest (see Milligan and
Neufeldt, 2001; Prause and Graham, 2007).
This article uses the following gradual
© 2017 The Japan Sociological Society
International Journal of Japanese Sociology doi: 10.1111/ijjs.12067
2017, Number 26
definition of the concept to capture broader
aspects of sexual behavior:
Definition. A person is called “asexual”if
he or she has few experiences of or inter-
ests in sexual behavior, such as kissing, dat-
ing, having sex, and forming romantic
relationships with a steady boyfriend or
girlfriend. A population is called “asexua-
lized”if a significant portion of the popula-
tion has become asexual.
Asexuality transforms intimate relation-
ships. Asexualized people can be expected
to have different life courses and lifestyles
from other people. Consequently, asexuali-
zation will transform patterns of romantic
lives and marriage on both an individual and
a societal level. In this way, the prevalence
of asexuality could be an important contrib-
utor to declining marriage and fertility rates
in Japan. Kobayashi and Osaki (2016) and
Kobayashi (2017) show that engaging in
sexual behavior (including kissing and
dating) is still likely to result in marriage.
The previous literature on this topic in
Japan has relied on qualitative evidence,
such as interviews and documents. There-
fore, it is necessary to analyze quantitative
data to capture a complete, accurate pic-
ture of asexuality in Japan.
Literature Review
What do we know about asexuality from
prior quantitative analyses? In the U.S.A.,
Kinsey et al. (1948) conducted a survey on
sexual activities. Laumann et al. (1994) ini-
tially highlighted the concept of asexuality.
Poston and Baumle (2010) distinguished
and compared the more specific concepts
of asexual behavior (having no sex), asex-
ual desire (having no attraction to sex) and
asexual identification (identifying oneself
as asexual). Using the 2002 National Sur-
vey of Family Growth, they analyzed
Americans aged 15–44 years. They
reported that asexual behavior was the
most prevalent of these three, followed by
asexual identification and desire among
both men and women. In the sample,
Figure 1. Changes in the way spouses are selected in Japan
Source: National Fertility Survey.
Figure 2. Percentage changes in the never-married rate by the age of 50 in Japan
Source: Population census.
14 Jun Kobayashi
© 2017 The Japan Sociological Society
11.9% of men responded to at least one
question on asexuality. This was 9.2% in
the female sample. Among the respon-
dents, 50–60% respondents exclusively
chose asexual behavior for both men and
women. About 30–40% respondents chose
asexual identification only. Asexual desire
was exclusively chosen by 3–5% respon-
dents. Consequently, they propose to meas-
ure asexuality in multiple dimensions.
In the U.K., Bogaert (2004) reported on
the emerging trend of asexual people,
defined as those without sexual desire.
In Japan, the Japanese Association for
Sex Education has conducted surveys of
junior high school, high school, and college
students approximately every six years
from 1974 to 2011 (Japanese Association
for Sex Education, 2013). The surveys
found that participation in sexual behavior
(dating, kissing, and having sex) generally
increased from 1974 to 2005 but then
mostly declined in 2011, with current
female students appearing to be more asex-
ual than male students.
Research Question
However, these data have been limited to
students, so it has remained unclear
whether the Japanese people as a whole
have become asexual. This study thus poses
the following research question, which
necessitated broader research to under-
stand trends in romantic relationships and
their effects on marriage patterns in the
whole Japanese population:
Research question. Has the Japanese adult
population become increasingly asexual,
and are there any gender differences with
regard to asexuality in Japan?
Hypotheses
The first hypothesis concerns the general
social trend. The literature has indicated
that both men and women may have
become asexual in recent years:
Hypothesis 1 (general trend of asexualiza-
tion). Younger people (i.e., those in their
thirties or younger) will be more asexual
than older generations among both men
and women.
With regard to gender gaps, the litera-
ture provides conflicting predictions.
Yamada and Shirakawa (2008) and Mor-
ioka (2008) suggest that there will be an
increase in male asexuality, whereas the
Japanese Association for Sex Education
(2013) indicates that women are more fre-
quently asexual. This article tests whether
either prediction is true:
Hypothesis 2 (gender differences). Young
men (in their thirties or younger) will be
more asexual than young women.
Hypothesis 20(gender differences). Young
women (in their thirties or younger) will be
more asexual than young males.
Methods
Data
This article uses data collected by the 2015
National Survey on Family and Career For-
mation in Japan, conducted in March 2015
(principal investigator: Jun. Kobayashi).
Because the survey was seeking detailed
information on private matters such as
romantic relationships and sexual behavior,
it was conducted in a web-based fashion via
the internet rather than through personal
interviews.
The population consisted of Japanese
men and women aged 20 to 69. The sample
was selected so as to reflect the 2010 popu-
lation census with regard to gender, five
age groups, and six standard geographical
areas. Of the 110,131 people contacted, a
non-representative sample of 12,007
responses was received, for a response rate
of 11%. This study used a subsample of
15Have Japanese People Become Asexual?
© 2017 The Japan Sociological Society
9,940 respondents who answered all ques-
tions relevant to the subsequent analyses
(5,159 men and 4,781 women). Table 1 pre-
sents descriptive statistics of the subsample.
Variables
The dependent variables selected for this
study were (i) the number of lovers
(i.e., steady boyfriends and girlfriends) that
respondents had while in junior high
schools and (ii) the number of lovers they
had after junior high school and up to the
present or the time of their first marriage, if
any. The number of lovers was chosen as
the focus variable because it addresses all
three criteria for asexuality identified by
Poston and Baumle (2010), i.e., asexual
behavior, asexual desire, and asexual
identification.
The survey asked respondents to indicate
how many steady boyfriends and girlfriends
they had (including their spouse, if any).
The possible answers ranged from “none”
to “15 or more.”Table 2 presents the
results and Figure 3 shows the distribution
of responses. On average, men had 2.7
lovers after junior high school and women
had 2.6. These results can be compared to
a previous finding of 2.7 lovers for men and
3.2 for women (Cabinet Office of
Japan, 2011).
Using questions from the Japanese Asso-
ciation for Sex Education (2013), the survey
also asked how many persons the respond-
ent had dated, kissed, or had sex with, both
during and since junior high school. These
variables were used to check the robustness
of the results. Descriptive statistics on these
questions are also shown in Table 2.
To test the hypotheses, age was used as
the independent variable. If we observe a
significant positive effect of age, it means
that the number of lovers a person has
increases with their age. Since the effects of
age could be nonlinear (even curvilinear),
age squared was also used. If we observe a
significant curvilinear effect of age, there
can be an inverted U-shaped curve with a
peak at a certain age. Here, the younger
the persons, the more lovers they have, and
the number then decreases at a certain age.
We regard these two cases as the evidence
of asexualization.
The analysis controlled for various fac-
tors of demographic and socioeconomic
status, such as marriage (married = 1, sin-
gle including separated and divorced = 0),
years of education (junior high school = 9,
high school = 12, junior college = 14, col-
lege = 16, graduate school = 18), full-time
worker in one’sfirst job (full-time = 1, other-
wise = 0), and equivalent income (in incre-
ments of 10,000 yen). These control
Table 1. Descriptive statistics on demographics and socio-economic status
Age Married
Years of
education
Full-time
at first job
Equivalent
income
Lovers in junior
high school (JHS)
Lovers
after JHS
Male
(5,159)
Mean 46.4 61.0%*** 14.6*** 77.4%*** 376.4*** 0.7** 2.7
Median 46 1 16 1 313 0 2
SD 13.4 0.5 2.2 0.4 242.5 1.6 2.8
Min 20 0 9 0 30 0 0
Max 69 1 18 1 2500 15 15
Female
(4,781)
Mean 46.6 70.0% 13.7 73.9% 349.1 0.6 2.6
Median 47 1 14 1 300 0 2
SD 13.4 0.5 1.9 4 222.1 1.4 2.5
Min 20 0 9 0 30 0 0
Max 69 1 18 1 2500 15 15
16 Jun Kobayashi
© 2017 The Japan Sociological Society
variables are applied only to the analysis of
romantic relationships after junior high
school, because students still in junior high
school have not yet attained the characteris-
tics covered by the control variables. When
examining the data on number of lovers after
junior high school, the study controls for the
number of lovers during junior high school.
Statistical Model
The hypotheses were tested using regres-
sion analyses, which were decomposed by
gender. In the analysis of the number of
lovers after junior high school, age effects
might lead to underestimating the results
for young people (especially those in their
twenties). This is because they are likely to
Table 2. Descriptive statistics on sexual behavior
In junior high school (JHS) After JHS until first marriage
Lovers Dating Kissing Sex Lovers Dating Kissing Sex
Male (5,159) Mean 0.7** 0.8** 0.6*** 0.5*** 2.7 3.9 3.3** 3.0***
Median 0 0 0 0 2 3 2 2
SD 1.6 2.0 1.9 1.8 2.8 4.1 3.9 3.8
Min000 0 0000
Max 15 15 15 15 15 15 15 15
Female (4,781) Mean 0.6 0.6 0.5 0.4 2.6 3.9 3.1 2.5
Median 0 0 0 0 2 3 2 1
SD 1.4 1.7 1.5 1.4 2.5 3.8 3.3 3.1
Min000 0 0000
Max 15 15 15 15 15 15 15 15
Notes: Nin parentheses. **P< 0.01; ***P< 0.001 in ANOVA on gender differences.
71.4%
15.5%
5.1%
3.5%
1.3%
1.3%
0.6%
0.3%
0.2%
0.1%
0.8%
74.2%
13.8%
4.9%
3.1%
1.4%
1.2%
0.5%
0.1%
0.2%
0.1%
0.5%
0.0% 40.0% 80.0%
0
(a) (b)
1
2
3
4
5
6
7
8
9
10-
Lovers in Jjunior high school
Male
Female
17.0%
25.9%
15.6%
16.1%
7.4%
7.8%
3.0%
1.6%
1.1%
0.7%
3.9%
13.6%
26.7%
19.5%
16.1%
7.8%
7.2%
2.7%
2.0%
1.2%
0.4%
2.9%
0.0% 15.0% 30.0%
0
1
2
3
4
5
6
7
8
9
10-
Lovers after junior high school
Male
Female
Figure 3. Distribution of lovers in (a) junior high school and (b) after junior high school until first
marriage, if any (%)
N= 5,159 for men and 4,781 for women.
17Have Japanese People Become Asexual?
© 2017 The Japan Sociological Society
have more romantic experiences after the
survey date that could increase the number
of lovers they have before getting married.
To avoid this problem, the article excludes
respondents who were in their twenties at
the time of the survey when analyzing the
number of lovers they had after junior high
school. According to Vital Statistics of
Japan, the average age when marrying was
31.1 years for men and 29.4 years for
women in 2015 (Ministry of Health, Labour
and Welfare Japan, 2015). Of course, the
number of lovers whom respondents had
while in junior high school cannot change
after the survey date (i.e., they are time-
invariant).
Results
Means by Groups
First, I examined the number of lovers in
junior high school by gender and age group
(Fig. 4, left side). For men, the number
peaks for respondents currently in their
fifties and then declines with younger
cohorts, implying an increased prevalence
of asexuality among young males. The
results for women, on the other hand, show
a peak in their thirties, implying little asex-
ualization. All differences between age
groups were significant in each gender.
The number of lovers after junior high
school is shown on the right side of Figure 3.
For men, there is a wide peak from respon-
dents in their thirties to those in their fifties;
for women, the peak is among participants
in their thirties. Therefore, neither men nor
women showed clear evidence of asexualiza-
tion. All age group differences were again
significant in each gender.
Regression Analyses on Lovers in
Junior High School
What happens when we test the roles of age
and age squared, controlling for socioeco-
nomic status and other variables? Table 3
reports the results of the regression analyses.
The sample is decomposed into men and
women to derive the effects of age.
0.54
0.64
0.72 0.76
0.61
0.67 0.71
0.60
0.53
0.42
0.00
0.50
1.00 (a) (b)
20s 30s 40s 50s 60s
(724,
633)
(1102,
996)
(1093,
985)
(1070,
1004)
(1170,
1163)
Lovers in junior high school
Male*, Female***
Male
Female
2.01
3.13
3.10 2.93
1.99
2.88
3.38
3.07
2.27
1.60
0.00
2.00
4.00
20s 30s 40s 50s 60s
(724,
633)
(1102,
996)
(1093,
985)
(1070,
1004)
(1170,
1163)
Lovers after junior high school
Male***, Female***
Male
Female
Figure 4. Number of lovers (Nin parenthesis, men above, women below) in (a) junior high school and
(b) after junior high school until first marriage, if any, by gender and by age group
*P< 0.05, ***P< 0.001 in ANOVA.
18 Jun Kobayashi
© 2017 The Japan Sociological Society
With regard to the number of lovers in
junior high school, both age and its square
had significant effects for men (the coeffi-
cients were 0.033 and −0.000, respectively).
Age squared had a negative coefficient,
indicating that age had an inverted U-
shaped curve with a peak at the age of
48.6 years. This suggests that for males, the
peak number of lovers was among respon-
dents in their late forties, with decreasing
numbers for younger cohorts.
For women, there was no significant
effect of age or age squared (the coeffi-
cients were 0.009 and −0.000, respectively).
This means that the number of lovers was
flat in shape, with no peak related to age.
We found significant interaction effects
of gender and age and of gender and age
squared in the sample for both genders
(results not reported).
Regression Analyses on Lovers after
Junior High School
Table 3 also shows the results for the num-
ber of lovers after junior high school. Here
we excluded respondents in their twenties
from the sample. For men, again, age had a
significantly positive effect and its square
had a significantly negative effect (coeffi-
cients of 0.144 and −0.002, respectively). So
this curve is an inverted U-shape, with a
peak at the age of 39.5 years.
For women, once again, age and its
square were not significant (coefficients of
0.000 and −0.001, respectively), corre-
sponding to a flat line without a peak.
We found significant interaction effects
of gender and age and of gender and age
squared in the sample for both genders
(results not reported).
Robustness Check
We analyzed the data on kissing, dating,
and having sex as a robustness check,
observing generally the same results both
in and after junior high school. We also
added respondents in their twenties to the
analysis of lovers after junior high school,
obtaining similar results, although now the
women had an inverted U-shaped curve
with a peak at the age of 32.7 years. When
we subtracted age squared from the regres-
sion analyses, we obtained similar results.
Nevertheless, women had significantly
Table 3. Regression results on number of lovers
Dependent variable
Lovers in junior high school Lovers after junior high school
Male Female Male Female
Age 0.033** 0.009 0.144*** 0.000
Squared age −0.000* −0.000 −0.002*** −0.001
Married dummy 0.162 −0.075
Years of Edu −0.038* −0.015
Full-time dummy −0.068 0.167*
Income 0.001*** 0.000*
Lovers in JHS 0.450*** 0.400***
R
2
0.001 0.005 0.117 0.149
N5,159 4,781 4,435 4,148
Shape Inverted U Flat Inverted U Flat
Peak 48.6 None 39.5 None
Notes: Values are unstandardized coefficients. “Lovers after junior high school”means those until the first marriage
if any. Lovers after junior high school are analyzed using only respondents in their thirties and older. “Full-time
dummy”indicates full-time at the first job = 1, otherwise = 0. Equivalent income is denoted in 10,000 of yen.
*P<0.05;**P< 0.01; ***P<0.001.
19Have Japanese People Become Asexual?
© 2017 The Japan Sociological Society
more lovers the younger they were. This
provides weak evidence that women are
“less”asexualized as they become younger.
Conclusion
Summary of Analyses
First, in terms of numerical averages, distribu-
tions showed that men had 0.7 girlfriends and
women had 0.6 boyfriends while in junior high
school. Men had 2.7 girlfriends and women
had 2.6 boyfriends from the time of their grad-
uation from junior high school to the time of
the survey or their first marriage, if any.
Second, regression analyses of the data
on male participants found an inverted U-
shaped curve for the number of lovers in
junior high school according to age, with a
peak at the age of 48.6 years. For women,
the number of lovers was consistent regard-
less of age, with no linear or curvilinear
trends. These findings imply a clear trend
toward asexual behavior among young men,
but no such trend among young women.
Third, as for the number of lovers after
junior high school, men had an inverted U-
shaped curve with a peak at the age of
39.5 years; women showed no linear or cur-
vilinear effects of age. Again, these findings
imply asexualized young men with young
women not asexualized. Comparing these
data with our hypotheses, we find that
Hypothesis 1 was partly supported, as a
trend toward asexualization was found for
men in their twenties and thirties but not
for women. Table 4 shows the results of
hypothesis testing.
The second pair of hypotheses dealt with
conflicting predictions on gender differences.
The results clearly imply that young men in
their twenties and thirties are more asexual
than the older generations, whereas young
women showed no such trend. Therefore,
Hypothesis 2 was supported and Hypothesis
20was not supported. This asexualization of
men could be one cause of the declining mar-
riage trends in Japan.
Answer to Research Question
Now, we can provide an answer to the orig-
inal research question as follows.
Answer to research question. In Japan,
young men have become asexual, but
young women are not as asexual as older
generations. The asexualization of men
could be an important contributor to the
decline in marriage rates.
According to Beck (1986) and Bauman
(1988), modern societies are experiencing
individualization. The increasing prevalence
of asexuality may be one reflection of this ten-
dency. Then, what might be the causes of this
asexualization? Figure 4 indicates that young
women are more active in romantic lives than
they were in older generations. If so, it could
be posited that young men have become
increasingly asexual or “herbivores”in
response to women becoming more sexually
aggressive “carnivores.”On the other hand,
the causality could be reversed; that is,
women may have become more sexually
active because men have became passive.
Our findings appear to contradict those
of the Japanese Association for Sex
Table 4. Test results of hypotheses
Hypothesis Test result
1 (General trend of asexualization). Younger people (aged 30 and below)
are more asexual than older generations, among both men and women
Partially supported (young women
were not more asexual)
2 (Gender differences). Young men (aged 30 and below) are more asexual
than young women
Supported
20(Gender differences). Young women (aged 30 and below) are more
asexual than young males
Not supported
20 Jun Kobayashi
© 2017 The Japan Sociological Society
Education (2013), which suggested there is
a greater tendency to asexualization among
women than among men. This might be
because our data treated adults while theirs
focused on sexual behavior of students. It
seems that people have different sexual
mechanisms as they develop.
Implications for Asian Societies
These findings could have significant impli-
cations for Asian countries and regions,
many of which are, like Japan, facing the
possibility of declining marriage and fertil-
ity rates. The present article suggests that
the asexualization of young men may be a
major factor underlying this decline in mar-
riage and fertility. Other cultures experien-
cing similar decreases in marriage and birth
rates may also look to asexualization as a
key underlying mechanism. If so, it is possi-
ble that other Asian societies may draw les-
sons from Japan’s experiences in the
future.
Next Step
First, the possible causal relationships
should be theoretically investigated. One
promising option is to adopt rational choice
approaches, which emphasize the causal
mechanisms of individuals using micro-
macro links (see Sato, 2013). For example,
Kobayashi (2017) has applied Becker’s
(1964) idea of human capital and Lin’s
(2002) work on social capital to understand
how people form romantic relationships in
Japan.
Second, this article used quantitative
survey data as evidence. To deepen our
understanding, a mixed methods approach
combining qualitative and quantitative
research would be helpful. Mixed method
approaches have attracted wide attention
in recent years (Tashakkori and Teddlie,
2002; Creswell and Clark, 2007). I have
begun doing qualitative research on this
topic by conducting interviews on the per-
sonal histories of romantic relationships
and marriage in the Philippines and Indo-
nesia (Fig. 5). This will help us understand
complicated mechanisms of sexual
behavior.
Acknowledgment
This work was supported by Japan Society
for the Promotion of Science Kakenhi
grant no. JP15H01969 (2015–18, principal
investigator: Jun Kobayashi) and by Seikei
University Center for Asian and Pacific
Studies Research Project (2014–16, princi-
pal investigator: Jun Kobayashi). A previ-
ous version of this article was presented at
an annual meeting of the Japan Sociologi-
cal Society as Kobayashi and Brinton
(a) (b)
Figure 5. Interviews in the Philippines (a, February 2016) and Indonesia (b, March 2016)
21Have Japanese People Become Asexual?
© 2017 The Japan Sociological Society
(2014). The author thanks Mary Brinton,
Kenji Kawabata, Hiroko Osaki, and two
reviewers for their constructive comments.
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JUN KOBAYASHI
DEPARTMENT OF CONTEMPORARY SOCIETIES, SEIKEI UNIVERSITY, 3-3-1,
Kichijoji-Kitamachi, Musasino-shi, , Tokyo 180-8633, Japan. Email: jun.kobayashi@fh.seikei.ac.jp
Received 19 January 2017; accepted 20 January 2017
22 Jun Kobayashi
© 2017 The Japan Sociological Society