Page 30 System Dynamics.'91
Change of Japanese Dietary Life
by Yuzuru Ooshika , Nobuyuki Shimizu and Junko Ooshika
Fukui Institute of Technology
Gakuen 3 , Fukui , Japan
Abstract
Change of Japanese dietary lives, especialy multifacialization, is one of
the most interesting phenomena in the Japanese society. It is closely related to
various social tendencies; contraction of the family size, shortage of the labor
force, increase of aged people, rising up of income levels, increase of the
number of married women with occupation and of unmarried women, progress of the
food technology, increase of the number of highly educated people, etc.
The present study is a trial of model building for the analysis of change
of Japanese dietary lives, based upon system dynamics. Simulation was carried
out up to the year 2005, for total dietary expense, expense for processed foods,
expense for dining-out, etc.
According to the simulation results, the fraction of expense for processed
foods and dining-out in total life expenditure increases more rapidly compared
with that of total dietary expense, and, in addition, it depends upon families’
income level. That means that the social: work division of preparing foods and
meals, which has, so far, been housewives’ work, is now rapidly advancing in
Japan, and that the tendency toward seeking pleasures in foods and meals is
getting stronger. These results suggests, with other changing social tendencies,
bipolarization of Japanese dietary lives, e.g.
proffesional cooking — domestic cooking
natural type — sophisticated type
tradition-oriented type ~— globalization type
isolate type — family type
practical type — pleasure-oriented type
1. Introduction
As the Japanese society is getting more affluent, big changes are observed
in the Japanese dietary life. The primary object of eating has, of course, been
to take various nutrients and keep good health, i.e., for physiological one.
But, as the developement of the human society, it has turned to seek pleasure
and tastefulness. Japanese, too, are not exception, and evident changes are seen
in the food expenditure of households, i.e., remarkable increase of the
proportion of the expenditure for dining-out and processed foods, which occupied
7% and 48%, respectively, in the total food expenditure per household in 1965,
while they increase to 15% and 55%, respectively, in 1985( Shokuryo Eiyo
System Dynamics '91 Page 31
Chosakai 1986). Especially, the trend should be noted that labor-saving food
with high value-added are preferred. Economically speaking, it means the
developement of social work devision of food processing service, the cause of
which is considered to be consumers’ behavior such as the increase of working
housewives and single-person households, the trend to seek pleasure in dietary
life with increasing income and leisure hours, the deversification of food
materials, and processing methods, and the needs for hand-made and sophisticated
cooking. The diversification of foods by generation differences, too,is promoted.
While young generations request processed foods, western-style foods, such as
breads and milk, and dining-out, old and middle generations prefer traditional
meal and dining-home.
Furthermore, depending on circumstances, same consumer lays weight
sometimes on economy and sometimes on sophistication and individuality. Thus,
while the total amount of food consumption does not increase, complication and
diversification in the consumer behavior grows rapidly ( Shokuryo Eiyo Chosakai
1986).
On the other hand, the role of food suppliers is production, import
processing, and distribution of foods. What connects the suppliers with the
consumers is all sorts of food information, and so, the developement of the mass
media, such as TV, newspapers, and magazines including suppliers’ advertisement,
has important infuences on the consumers’ behavior.
2. System Dynamics Model
The purpose of the present paper is to investigate the influences of social
and economic environment and the life style upon the Japanese dietary life and
to predict the future change.
socio-economic
environment
family life
~ a
a ot living
food industry
ae dietary life
Fig.1 Sector structure
Page 32
System Dynamics '91
Main
interest is concentrated on the change of the use of processed foods
and the frequency of dining-out and the influence of the economic growth on
them. Fig.1 shows the sector structure of the SD model. As shown in the Figure,
the socio-economic sector is not included in feedback loops, i.e., it is treated
exogeneously.
2.
1 Exogeneous Sector
Exogeneous variables used to represent the socio-economic sector are as
follows, and given as table functions.
1) AC: Proportion of those who have had formal education over 14 years in the
2) KK:
3) AA:
4) 1S
5) PO:
6) GN:
2.
1)
whole population from 15 to 64 years of age, estimated from government
statistics (Ministry of Education 1986, Ministry of Health and Welfare
1988).
Average number of persons per household (Ministry of Health and
Welfare 1988) .
Proportion of population over 65 in the whole population ( Ministry of
Health and Welfare 1988).
: Amount of annual information supply, taking 100 in 1980 ( Council of
National Life 1986).
Population ( Ministry of Health and Welfare 1988). ‘
Gross private final consumption ( Bank of Japan 1985). After 1986,
7 cases ( 0,1,2,3,4,5,and 6% annual growth rate) are assumed.
The values of the above variables up to 1985 are actual date and those
after 1986 are projected ones as shown in the references.
2 Model and Endogeneous Variables
Fig.2 shows the flow diagram. The model has four level variables.
LEO
: Annual expenditure for leisure-type dining-out per capita. Using
Governments’ data, it is defined as the expenditure for items which
are sensitive to the level of household income, i.e., which have
large standard deviations.
: Annual expenditure for practical dining-out per capita, i.e., for
items other than LEO .
: Annual expenditure for dining-home per capita.
: Annual expenditure for processed foods per capita. Processed foods
mean those other than grains and fresh foods ( Statistics Bureau
1985).
Other variables are auxiliary variables, whose meaning is as follows:
1) TOE: Annual total food expenditure per capita.
2) TOO: Annual total expenditure for dining-out per capita.
cs
IN
cL
: Self-cooking, i.e., annual expenditure for foods other than dining-
out and processed foods per capita.
: Annual income per household.
: Desire for good living expressed as an index between 0 and 100.
Hereafter indices take values between 0 and 100.
System Dynamics '91 Page 33
6) NC : Consciousness of nutrition and health expressed as an index.
7) NI: Annual supply of nutrition and health information.
8) F T : Level of food technology.
9) ER : Extent of leisure element involved in dining-out, expressed as an
index.
10) LT: Annual leisure hours.
11) HW : Hours for household works.
12) T I : Proportion of married couples in which both wife and husband work.
13) WT : Hours for work per household.
14) F I : Annual supply of food information, expressed as an index.
15) LO: Proportion of dining-lone.
16) CW: Hours for cooking work.
17) G1:GN/PO
18) TO: Criterion for decision whether one increases or decreases ones’ food
expenditure.
3. Results
Simulations were carried out for the annual growth rates 0,1,2,3,4,5, and
6%, respectively, from 1985 to 2005. The standard model: is the one for the
growth rate 3%.
3. 1 Standard model
Engel's coefficient decreres from 29.2% in 1985 to 23.7% in 2005. But it
does not have much sense, becaue it is not a good measure for a level of living
in an affluent society. In Fig.3 is shown the change of TOE, PFS, and
TOO. The increase of TOE between 1985 and 2005 is about ¥130,000, the
major part of which is that of TOO. The increase of PFS is around
¥80,000. It means that the expense by social work division increase by ¥210,000
while the self-cooking (CS) decreases by ¥80,000. It should be noted that CS
includes only the expense for materials but PFS and TOO include also the
expense for service and processing.
Furthermore, PFS occupies always about 50% in TOE, and the increase
of TOO is, therefore, balanced by the decrease of CS. The possible reasons
are 1) the trend of searching convenience owing to the increase of working
married couples and the decrease of population per household, and 2)
sophistication owing to the rising up of living level, the increase of leisure
hours, and the trend of pleasure-seeking in dietary life, as shown in Fig.9.
3. 2 Economic Growth and Dietary Life
In Figs.4 to 9 are shown TOE, TOO, PFS, proportion of TOO and
PFS in TOE, and that of LEO in TOO, respectively.
Though the change of TOO is not noticeable for the growth rate 2%, the
increase of TOO is large. It increases to 1.5 times in 2005 even under 0%
growth where TOE is decreased, and attains 6 times under 6% growth. That
means that housewives’ work which has been carried out personally turnes to be
Page 34 System Dynamics '91
socialized and purchased as labor service in the market with increasing income.
The increase of PFS is much smaller than of TOO, probably because
processed foods are mainly for convenience and poor in pleasure-seeking effect
in contrast with dining-out. This is more evident by Fig.7 to 9. While the
proportion of TOO in TEO and of LEO in TOO are always much
increased, that of PFS in TEO does not change under 0% growth, and, under
6% growth, it once increases but decreases again. Thus, it proves that the use
of processed foods is only transient and does not mean true high level of the
dietary life.
References
Bank of Japan 1985, International Comparative Statistics No.24, Nihon Shinyo
Chosa.
Council of National Life 1986, Indices of National Life, Printing Bureau.
Ministry of Education 1986, Summary of Statistics of Ministry of Education.
Printing Bureau.
Ministry of Health and Welfare 1988, Trend of Population, Kosei Tokei. Kyokai.
Shokuryo Eiyo Chosakai 1986. Foods, Nutritions, and Health, Ishiyaku Shuppan.
Statistics Bureau 1985, Annual Reports on Household Budget, Statistics Bureau.
Appendix | SD equations
A TAA.K = TABLE (AA, TIME. K, 50,100, 5)
A TKK.K = TABLE (KK, TIME. K,50, 100, 5)
A TAC.K = TABLE (AC, TIME.K, 50, 80,5)
A TIS.K = TABLE (IS, TIME. K, 50, 100, 5)
A TPO.K = TABLE (PO, TIME. K, 50, 100, 5)
A TGN.K = TABLE (GN, TIME.K,50, 100, 5)
A IN.K = BIN(2).K*(BTI (1) .K-BTI (2) .K) #1.045
A CL.K = MAX(0, ((BIN(1) . K-BIN (2). K) /BIN (2). K+TAC. K/100+LT. K/1440- (BPFS (1) .K
~BPFS (2) . K) /BPFS (2) . K) #100/3)
A NC.K = (CL. K#3+ (BIN (1) . K-BIN (2) . K) #100/BIN (2) .K-FT. K#0. 5) /2
A NI.K = TIS.K
A FT.K = (NI. K+ ((BPFS (1). K-BPFS (2) . K) /BPFS (2). K) «100) /2
A ER.K = MAX(0, (((BIN (1). K-BIN (2) .K) #100/BIN (2) .K) #2+CL. K+ (BLT (1) .K
~BLT (2) . K) #100/BLT (2) . K+F1. K#2) /4
A LT.K = BLT(2) .K- ((BHW (1). K-BHW (2). K) + (BHT (1) . K~BWT (2) . K) /2)
A HW.K = (BHW(2).K* (BTI (1). K/BTI (2) .K) - (BHT (1). K-BWT (2) .K) /2) *0. 98
A TI.K = (BTI (2). K+ ( (BKK (1) . K-BKK (2) . K) /BKK (2) . K+ TAC. K/100+ (BPFS (1) .K
~BPFS (2) . K) /BPFS (2) . K+ (BPEO.(1) . K-BPEO (2) . K) /BPEO (2) .K) /4) *1. 01
A WT.K = (BWT (2). K-((450/(100+TI.K)) *TKK. K) /100) #0. 99
A FI.K = MAX(0, ( (FT. K+ (BLEO (1) . K-BLEO (2) . K) *100/BLEO (2) . K) /2) * (BIS (2) . K)
*100/BLEO (2) . K) /2) * (BIS (1) . K/BIS (2) . K) )
System Dynamics '91 Page 35
A LO.K = ((BKK (1) . K-BKK (2) . K) *100/BKK (2) . K+TI.K) /2
A CW.K = (HW. K*TKK. K/ ((1+ (TAA. K+LO. K) /100) #2. 9) ) 1.005
A CS.K = (CL.K/100+BNC (1) . K/BNC (2) . K+0. 65) #2920
A G1.K = TGN.K/TPO.K
A TO.K = (G1.K*0. 45-TOE. K) /TOE.K
A TOE.K = LEAI.K+TOO.K
A TOO.K = LPEO. K+LLEO.K
R RPFS.KL = (((FI.K-NC. K) /100* (BCW (2) . K/BCW (1) . K) ABS (LEAI. K-LPFS. K)
*T0.K+7500) #0. 44
RPEO. KL = ( (ER. K/100+ (1-BCW (1) .K/BCW (2) .K)) #T0. K*LPEO. K-CS. K/30+4500) *0.19
RLEO.KL = ((ER.K/100) *#TO. K*LLEO. K- (CS. K#2/30) +4500) *0. 34
REAI.KL = CS. K+ (BPFS (1) . K-BPFS (2) . K)
LPFS.K = LPFS. J+DT#RPFS. JK
LPEO.K = LPEO. J+DT*RPEO. JK
LLEO.K = LLEO. J+DT*#RLEO. JK
LEAI.K = LEAI. J+DT*REAI. JK
BKK = BOXLIN(2, 1)
BIS = BOXLIN(2, 1)
BIN = BOXLIN(2, 1)
BNC = BOXLIN(2, 1)
BNI = BOXLIN(2, 1)
BLT = BOXLIN(2, 1)
BHW = BOXLIN(2, 1)
BTI = BOXLIN(2, 1)
BHT = BOXLIN(2, 1)
BCW = BOXLIN(2, 1)
BPFS = BOXLIN (2,1)
BPEO = BOXLIN (2,1)
BLEO = BOXLIN (2,1)
BEAI = BOXLIN (2,1)
BKK (1).K = TKK.K
BIS(1).K = TIS.K
BIN(1).K = IN.K
BNC (1).K = NC.K
BNI (1).K = NI.K
BLT(1).K = LT.K
BHW(1).K = HW.K
BTI(1).K = TI.K
BWT(1).K = WT.K
BCW(1).K = CW.K
BPFS(1).K = LPFS.K
BPEO(1).K = LPEO.K
BLEO(1).K = LLEO.K
BEAI(1).K = LEAI.K
i i ol el ed)
LPFS = 131346
Page 36 System Dynamics '91
LPEO = 15347
LLEO = 18382
LEAI = 248447
BKK = BOXLOAD (3, 29, 1)
BIS = BOXLOAD (96, 1)
BIN = BOXLOAD (2586, 1)
BNC = BOXLOAD (18, 1)
BNI = BOXLOAD (96, 1)
BLT = BOXLOAD (411, 1)
BHW = BOXLOAD (163, 1)
BTI = BOXLOAD (44.7, 1)
BWT = BOXLOAD (242, 1)
BCW = BOXLOAD (167, 1)
BPFS = BOXLOAD (121411, 1)
PrPrrreazeaaazazastzazazeze2a2z2z2z2z2z2zZz
BPEO = BOXLOAD (13190, 1)
BLEO = BOXLOAD (16251, 1)
BEAI = BOXLOAD (231099, 1)
RO.K = (TOO. K/TOE. K) *100
RI.K = ((LEAI.K-LPFS. K) /TOE. K) «100
RP.K = (LPFS.K/TOE. K) #100
RE.K = (TOE.K/G1.K) *100
RL.K = (LLEO. K/TOO. K) *100
