TRENDS IN NATIONAL NUTRITIONAL SURVEY OF JAPAN SHUHEI KOBAYASHI National Institute of Nutrition, Tokyo, Japan*
ABSTRACT The nutritional status of the Japanese has been measured and evaluated annually on a nationwide scale since the first National Nutrition Survey was carried out in 1946. Changes in dietary intake levels could thus be monitored systematically at a national level. According to the results observed, the whole 50 years ofthe postwar period can be divided into three stages in terms of dietary intakes and their postulated health outcome. Although it has certain limitations for the purpose of analysis the survey has performed a remarkable role in throwing light upon the general trends and current status of nutrition in Japanese populations and thereby enabling a successful nutritional policy to be established.
INTRODUCTION
Over the past 50 years, the nutritional status of the Japanese has undergone tremendous change, and this has been associated with a shift of disease pattern from ·an infectious-disease dominated to a non-communicable disease type. These changes seem to be closely related to each other, and they agree with the results of many population studies carried out in western industrialized countries. Throughout this period, the Japanese government has carried out a number of surveys and policy interventions on the lifestyles of Japanese people, including their dietary habits. The purpose ofthis paper is to present a brief description of the National Nutrition Survey of Japan, one of the representative surveys of this series, and to discuss its role for monitoring nutritional status, thereby forming a background for establishing dietary and health promotion policies in Japan. METHODOLOGY
A historical and methodological overview is shown in Table 1. The dietary *National Institute of Health and Nutrition, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162, Japan 91
Downloaded from nah.sagepub.com at OAKLAND UNIV on June 1, 2015
92
intake was measured by weighing foods before or after cooking (as well as weighing what remained after each meal). Additional information was gained from occasional interviews. The results were then used for calculating average daily energy and nutrient intake per capita with the Japanese Standard Food Composition Table. TABLE 1 Outline of the National Nutrition Survey Started at:
1945 (limited to Tokyo area) 1946 (Nationwide) 4/year(1946-1963) 1/year ( 1964-) Ministry of Health and Welfare Ministry of Health and Welfare l. Food intake survey 2. Anthropometry with optional physical and biochemical measurements. 3. Optional questionnaire About 600 households (20,000 in total) (all residents of randomly selected districts (about 300)) Three consecutive days inN ovember excluding Saturday, Monday, and holidays Mainly dietitians and related professionals of local health centers
Frequency: Designed by: Organized by: Composed of:
Survey subjects: Survey period Conducted by:
26
240
22D2on IU
18 0
'n 16•u
,..-----.,.-
14 0
0
•~
Iron
Protein
251
12 0 10 0 80
6o-
-1-151- -15s-
t-121
--~
103
89_
40 20
--123
107
-
-
0
Energy
Calcium
A
B, Vitamins
Figure l.
Current nutrient intake of Japanese
Downloaded from nah.sagepub.com at OAKLAND UNIV on June 1, 2015
c
93
Other than dietary intake, some regular or optional examinations have been done, which included body height and weight, skinfold thickness and blood pressure measurements. Haematological and biochemical data were obtained occasionally by taking blood samples from certain defined age or sex populations. Some questionnaires on diet, exercise and other habitual elements were also completed. RESULTS AND DISCUSSION
Current data on the average intake for energy and measured nutrients 1 are illustrated in Figure 1. For most of the major nutrients as well as for energy, intake levels are well above the Japanese Recommended Dietary Allowance (RDA)2 as indicated by a solid line in the figure. This situation together with kcal
2600 2400 Energy
2200 2000 Protein
g
80 60 40 20 400 g Carbohydrate
350 300 1950
60
70
75
77
79
81 82 year
Figure 2. Annual change in intakes of some nutrients (per capita per day) (The National Nutrition Survey)
Downloaded from nah.sagepub.com at OAKLAND UNIV on June 1, 2015
94
a decrease in salt and fat intake may contribute to the current favorable health status of the Japanese, where lower death rates have been noticed from both infectious and non-communicable diseases. The standardized survey method used throughout the study period has allowed us to observe an overall figure for changing intake levels. The changes in nutrient intake during 1950 to the early 1980's are shown in Figure 2. The intake of energy maintains almost a constant level while that of protein shows a gradual increase and that of fat increases remarkably with decreasing carbohydrate intake. These results are consistent with the assumption that the dietary pattern of the Japanese is tending to approach that of western industrialized countries. · We then look at changes in the dietary pattern in terms of food group intake (Figure 3). The intake of rice, which has been regarded as an integral element in Japanese traditional diet, was found to be markedly reduced. This may have contributed to the decreased intake of carbohydrate mentioned above. In contrast, milk, dairy products, and egg intakes increased, with a distinct but slight rise of meat intake, all of which may be responsible for the increasing fat and animal protein intake levels. Figure 4 illustrates a more detailed aspect of the changes in intake patterns, which may indicate another unique feature in the behavioral changes of eating. These are indicated by a characteristic discontinuity in the pattern of intake of food, such as fruit, which occurred around the mid-
(%)
Changes in food intake by foe>d grup
180 160 140 120
lBB 80 68 48 20 0 Figure 3.
1975
'
1980
1985
Changes in food intake by food group.
Downloaded from nah.sagepub.com at OAKLAND UNIV on June 1, 2015
1989
Downloaded from nah.sagepub.com at OAKLAND UNIV on June 1, 2015
(g)
Figure 4.
1965
20
40
J>
80
100
120
-'
/
/
/
1975
---...
Changes of intake of food groups.
----
,
,,
,,"'"'/'
/
, ,' ' ' ' \
'
'
'
1985
egg'S
--------
fish
./ milk ~ and dairy pro~uctrs
, ,,
140~------------~
(g )
·········-- .. _
----"'C
I.
•
I
...........................
--······
,-fruits ", 0
/'. "'
wheat
"'-----
0
.,
-"
colored vegetab les
_, .... .... -· .-...··· '-- -----~
~
pota toes
! ,', -·····---~,~~-~;:c-.'""',-:.::= ~ -------
.I
other
1965
1975
1985
0~------~-----L----~~-----~--~
50
100
150
200
250
300
350~r-----------------------------~
Vl
1.0
96
1970s. As shown in the figure, fruit intake rapidly increased during the "economic growth period" beginning in the early 60s, peaked at 1975, and then declined. Intake of meat also increased until around 1974. The discontinuity seems to be related to the period of "oil crisis", which was said to have a tremendous impact, and to have caused a change in the attitude of Japanese people towards their own lifestyle. Interestingly, these tendencies have remained even after the recovery of the national economy. It may be assumed that these behavioral changes, together with a growing wish to adopt a healthy lifestyle, contributed to the slowing of "westernization" in dietary habits. Based upon observations described above, it may be pertinent to divide the whole postwar period into three stages: 1, the first ten years, when traditional diet dominated, with severe undernutrition, including a deficiency of animal protein and essential micronutrients, making people more susceptible to infectious diseases, 2, an economic-growth period beginning in the late 1950s when intakes of foods of animal origin, such as milk, eggs and meats increased rapidly while those of vegetables, potatoes and seaweeds reduced. Disease profiles shifted from the infectious diseaseto a noncommunicable chronic disease-dominated type, 3, "after the 'oil crisis'," when slowing of the "westernization of dietary habit" took place, with a reduction of salt intake, while an increased elderly population brought about a series of new health problems. To interpret the results of the National Nutritional Survey, there are inevitably some methodological limitations, since the survey method is household-based and provides only average figures for the whole population which is composed of various age and sex groups. Information about particular age groups, such as preschoolchildren, elderly people, etc. is essential for analyzing current health problems arising from dietary abnormality and thereby establishing effective health policies.
REFERENCES 1. Report from the 1989 National Nutrition Survey: Ministry of Health and Welfare, Japan, 1991. 2. Recommended Dietary Allowances For Japanese, 4th Edition: Ministry of Health and Welfare, Japan, 1989.
Nutrition and Health, 1992, Vol. 8, pp. 91-96 0260-1061/92 $10 © 1992 A B Academic Publishers. Printed in Great Britain
Downloaded from nah.sagepub.com at OAKLAND UNIV on June 1, 2015
ABSTRACT The nutritional status of the Japanese has been measured and evaluated annually on a nationwide scale since the first National Nutrition Survey was carried out in 1946. Changes in dietary intake levels could thus be monitored systematically at a national level. According to the results observed, the whole 50 years ofthe postwar period can be divided into three stages in terms of dietary intakes and their postulated health outcome. Although it has certain limitations for the purpose of analysis the survey has performed a remarkable role in throwing light upon the general trends and current status of nutrition in Japanese populations and thereby enabling a successful nutritional policy to be established.
INTRODUCTION
Over the past 50 years, the nutritional status of the Japanese has undergone tremendous change, and this has been associated with a shift of disease pattern from ·an infectious-disease dominated to a non-communicable disease type. These changes seem to be closely related to each other, and they agree with the results of many population studies carried out in western industrialized countries. Throughout this period, the Japanese government has carried out a number of surveys and policy interventions on the lifestyles of Japanese people, including their dietary habits. The purpose ofthis paper is to present a brief description of the National Nutrition Survey of Japan, one of the representative surveys of this series, and to discuss its role for monitoring nutritional status, thereby forming a background for establishing dietary and health promotion policies in Japan. METHODOLOGY
A historical and methodological overview is shown in Table 1. The dietary *National Institute of Health and Nutrition, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162, Japan 91
Downloaded from nah.sagepub.com at OAKLAND UNIV on June 1, 2015
92
intake was measured by weighing foods before or after cooking (as well as weighing what remained after each meal). Additional information was gained from occasional interviews. The results were then used for calculating average daily energy and nutrient intake per capita with the Japanese Standard Food Composition Table. TABLE 1 Outline of the National Nutrition Survey Started at:
1945 (limited to Tokyo area) 1946 (Nationwide) 4/year(1946-1963) 1/year ( 1964-) Ministry of Health and Welfare Ministry of Health and Welfare l. Food intake survey 2. Anthropometry with optional physical and biochemical measurements. 3. Optional questionnaire About 600 households (20,000 in total) (all residents of randomly selected districts (about 300)) Three consecutive days inN ovember excluding Saturday, Monday, and holidays Mainly dietitians and related professionals of local health centers
Frequency: Designed by: Organized by: Composed of:
Survey subjects: Survey period Conducted by:
26
240
22D2on IU
18 0
'n 16•u
,..-----.,.-
14 0
0
•~
Iron
Protein
251
12 0 10 0 80
6o-
-1-151- -15s-
t-121
--~
103
89_
40 20
--123
107
-
-
0
Energy
Calcium
A
B, Vitamins
Figure l.
Current nutrient intake of Japanese
Downloaded from nah.sagepub.com at OAKLAND UNIV on June 1, 2015
c
93
Other than dietary intake, some regular or optional examinations have been done, which included body height and weight, skinfold thickness and blood pressure measurements. Haematological and biochemical data were obtained occasionally by taking blood samples from certain defined age or sex populations. Some questionnaires on diet, exercise and other habitual elements were also completed. RESULTS AND DISCUSSION
Current data on the average intake for energy and measured nutrients 1 are illustrated in Figure 1. For most of the major nutrients as well as for energy, intake levels are well above the Japanese Recommended Dietary Allowance (RDA)2 as indicated by a solid line in the figure. This situation together with kcal
2600 2400 Energy
2200 2000 Protein
g
80 60 40 20 400 g Carbohydrate
350 300 1950
60
70
75
77
79
81 82 year
Figure 2. Annual change in intakes of some nutrients (per capita per day) (The National Nutrition Survey)
Downloaded from nah.sagepub.com at OAKLAND UNIV on June 1, 2015
94
a decrease in salt and fat intake may contribute to the current favorable health status of the Japanese, where lower death rates have been noticed from both infectious and non-communicable diseases. The standardized survey method used throughout the study period has allowed us to observe an overall figure for changing intake levels. The changes in nutrient intake during 1950 to the early 1980's are shown in Figure 2. The intake of energy maintains almost a constant level while that of protein shows a gradual increase and that of fat increases remarkably with decreasing carbohydrate intake. These results are consistent with the assumption that the dietary pattern of the Japanese is tending to approach that of western industrialized countries. · We then look at changes in the dietary pattern in terms of food group intake (Figure 3). The intake of rice, which has been regarded as an integral element in Japanese traditional diet, was found to be markedly reduced. This may have contributed to the decreased intake of carbohydrate mentioned above. In contrast, milk, dairy products, and egg intakes increased, with a distinct but slight rise of meat intake, all of which may be responsible for the increasing fat and animal protein intake levels. Figure 4 illustrates a more detailed aspect of the changes in intake patterns, which may indicate another unique feature in the behavioral changes of eating. These are indicated by a characteristic discontinuity in the pattern of intake of food, such as fruit, which occurred around the mid-
(%)
Changes in food intake by foe>d grup
180 160 140 120
lBB 80 68 48 20 0 Figure 3.
1975
'
1980
1985
Changes in food intake by food group.
Downloaded from nah.sagepub.com at OAKLAND UNIV on June 1, 2015
1989
Downloaded from nah.sagepub.com at OAKLAND UNIV on June 1, 2015
(g)
Figure 4.
1965
20
40
J>
80
100
120
-'
/
/
/
1975
---...
Changes of intake of food groups.
----
,
,,
,,"'"'/'
/
, ,' ' ' ' \
'
'
'
1985
egg'S
--------
fish
./ milk ~ and dairy pro~uctrs
, ,,
140~------------~
(g )
·········-- .. _
----"'C
I.
•
I
...........................
--······
,-fruits ", 0
/'. "'
wheat
"'-----
0
.,
-"
colored vegetab les
_, .... .... -· .-...··· '-- -----~
~
pota toes
! ,', -·····---~,~~-~;:c-.'""',-:.::= ~ -------
.I
other
1965
1975
1985
0~------~-----L----~~-----~--~
50
100
150
200
250
300
350~r-----------------------------~
Vl
1.0
96
1970s. As shown in the figure, fruit intake rapidly increased during the "economic growth period" beginning in the early 60s, peaked at 1975, and then declined. Intake of meat also increased until around 1974. The discontinuity seems to be related to the period of "oil crisis", which was said to have a tremendous impact, and to have caused a change in the attitude of Japanese people towards their own lifestyle. Interestingly, these tendencies have remained even after the recovery of the national economy. It may be assumed that these behavioral changes, together with a growing wish to adopt a healthy lifestyle, contributed to the slowing of "westernization" in dietary habits. Based upon observations described above, it may be pertinent to divide the whole postwar period into three stages: 1, the first ten years, when traditional diet dominated, with severe undernutrition, including a deficiency of animal protein and essential micronutrients, making people more susceptible to infectious diseases, 2, an economic-growth period beginning in the late 1950s when intakes of foods of animal origin, such as milk, eggs and meats increased rapidly while those of vegetables, potatoes and seaweeds reduced. Disease profiles shifted from the infectious diseaseto a noncommunicable chronic disease-dominated type, 3, "after the 'oil crisis'," when slowing of the "westernization of dietary habit" took place, with a reduction of salt intake, while an increased elderly population brought about a series of new health problems. To interpret the results of the National Nutritional Survey, there are inevitably some methodological limitations, since the survey method is household-based and provides only average figures for the whole population which is composed of various age and sex groups. Information about particular age groups, such as preschoolchildren, elderly people, etc. is essential for analyzing current health problems arising from dietary abnormality and thereby establishing effective health policies.
REFERENCES 1. Report from the 1989 National Nutrition Survey: Ministry of Health and Welfare, Japan, 1991. 2. Recommended Dietary Allowances For Japanese, 4th Edition: Ministry of Health and Welfare, Japan, 1989.
Nutrition and Health, 1992, Vol. 8, pp. 91-96 0260-1061/92 $10 © 1992 A B Academic Publishers. Printed in Great Britain
Downloaded from nah.sagepub.com at OAKLAND UNIV on June 1, 2015
