International Vegetarian Union (IVU)
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32nd World Vegetarian Congress 1996
[Vegetarian Summerfest '96: A World Vegetarian Congress]

Comparing Nutrition and Health of Japanese High School Students: SDA Vegetarians and Non-vegetarians
from EVU News, Issue 4 / 1996

About the authors: (Department of Home Economics, Osaka Shin-Ai College)

[photo: Dr Kakimoto] Mitsuru KAKIMOTO D.D. Sc., Ph.D., M.S.A.
Mitsuru Kakimoto is president of the 日本ベジタリアン協会 - Japanese Vegetarian Society (M) and vicepresident and professor at Osaka Shin-Ai College (OSC), Japan.He has recently been elected as a member of the IVU Council.
He has been studying vegetarians from a viewpoint of medical science and dietetics and is a pioneer in Japan in this field. He has written theses in Jap. J. Nutr. and other journals. He is the author of Introduction of Healthy Vegetarian.

Yumi WATABE M.S.H.E.
Yumi Watabe is a trustee of JVS and associate professor at OSC. She makes a special study of food science and dietetics. She has written theses in J. Home Eco. Jap. and other journals.

Akinori TAKAI D.Sc., Ph.D.
Akinori Takai is the director of JVS and a professor at OSC. He is a member of the New York Academy of Science. He makes a special study of environmental science. He has written theses in Cytobios and other journals.

Kazuhiro MATSUO B.A.
Kazuhiro Matsuo is the director of JVS and lecturer at OSC. He is a columnist and writes columns in major newspapers in Japan such as Asahi.

Masahide SAKYU M.Ed. Masahide Sakyu is a member of JVS and assistant at OSC. He studies linguistics. He is a translator and is introducing vegetarianism to Japan.

ABSTRACT
A food intake survey for three consecutive days was conducted and the Cornell Medical Index-Health Questionnaire papers (C. M. I.) were given to Japanese high school students who were 14 to 16 years old: 120 SDA vegetarians and 120 nonvegetarians. The following results were obtained:

  1. Each mean value of the nutrients consumed, except for niacin, met the requirements of dietary allowance for SDA vegetarians.
    The energy, calcium and iron intakes for non-vegetarians showed lower mean values compared with the values of the dietary allowance.
  2. Height, weight, obesity and emaciation were not significantly different between the two groups.
  3. As a results of C. M. L, the subjective symptoms of alimentary system of SDA vegetarians were significantly less than those of non-vegetarians.

Considering the results, we would like to recommend the vegetarian diet and spread it all over Japan.

1. Introduction

A lot of research reports concerning nutrition and health of vegetarians exist in the United States. They say death rate for vegetarians from various cancers is lower than that of people who eat a non-vegetarian diet and that incidence rate for vegetarians of geriatric diseases such as ischaemia, heart disease, diabetes, osteoporosis and hypercholesterolemia is low.

In 1988, the American Dietetic Association issued the commentary which technically supported a vegetarian diet. The commentary reported that vegetarians rarely contract diabetes.

The nutrient problems such as shortages of vitamin B12 in a complete vegetarian diet, where only food of plant origin is eaten, were pointed out. There is not so much research into the vegetarians during the period of growth, and moreover, the amount of the research into the vegetarian diet on which the Japanese are targeted is extremely small.

Then, the authors studied Japanese students who lived in a dormitory and lived on the Lacto-ovo-vegetarian diet of the SDA method, and students of the same age, junior high school and high school students, in Osaka Prefecture, who ate a non-vegetarian diet. The nutrition and health of the students were investigated in this study. We used the Cornell Medical Index-Health Questionnaire (abbreviated C.M.I.) to examine the health condition of the students.

2. Method

Subjects
The vegetarians investigated were students from 14 to 16 years old, who studied at Hiroshima San-iku Gakuin, a school in Hirosima Prefecuture. The non-vegetarian group consisted of junior high school and high school students, who lived on a non-vegetarian diet. The two groups each consisted of 120 students: 60 males and 60 females. Both the C.M.I. and the food intake survey of the two groups were conducted.

Table 1: Number of Subjects shows the number of students with valid answers.

Table 1 - Number of Subjects:
Group C.M.I. Food Intake Survey
Vegetarians 109 (Male: 59 Female: 50) 109 (Male: 59 Female: 50)
Non-vegetarians 107 (Male: 57 Female: 50) 82 (Male: 42 Female: 40)

Investigation
The C.M.I. was used to investigate the physical condition of the subjects. This questionnaire was developed for the purpose of detecting the mental and physical subjective symptoms for a short period of time. The question items were translated into Japanese in this survey.

The mental and physical subjective symptoms are shown in Table 2: The Section on the Cornell Medical Index. In this particular survey, we used 160 question items relating to physical subjective symptoms for males and corresponding 162 question items for females.

The food intake investigation was conducted for three consecutive weekdays to investigate the nutrient intake. The percentage of the dietary allowance of each nutrient was calculated according to stature, weight, and the intensity of daily activity (middle degree) of the subjects.

Table 2 - The Sections on the Cornell Medical Index:
Section Questions referring to N. of
Questions
- Section Questions referring to No. of
Questions
A Eyes and ears 9 - K Miscellaneous diseases 15
B Respiratory system 18 - L Habits 6
C Cardiovascular system 13 - Mood and Feeling Patterns
D Digestive tract 23 - M Inadequacy 12
E Musculoskeletal system 8 - N Depression 6
F Skin 7 - O Anxiety 9
G Nervous system 15 - P Sensitivity 6
H Genitourinary system 11 - Q Anger 9
I Fatigability 7 - R Tension 9
J Frequency of illness 9 - . Total 195

3. Results

We would like to talk about the nutrient intake survey.

The vegetarian students ate meals at a dormitory cafeteria. The meals included dishes made from soybean protein and wheat protein. Main dishes were such as rice and bread. The students were free to have fruit and beverage of their own choice. For three consecutive days, they wrote on the forms what they ate at each meal. The non-vegetarian students wrote down the kind and amount of the food they ate.

In the vegetarian students of both sexes, the dietary intake average value of each nutrient except niacin fulfilled the recommended dietary allowance. On the other hand, in the non-vegetarian students of both sexes, the dietary intake average value of energy, calcium and iron did not meet the recommended dietary allowance. In both sexes, the vegetarian diet group痴 intakes of energy, lipid, calcium, iron, vitamin A, and vitamin B2 were significantly higher than those of the non-vegetarian group.

Niacin is the only nutrient whose intake is higher in non-vegetarian than in vegetarians and the difference in the female students was significant. Thus, the lack of inorganic substances such as calcium and iron was as conspicuous as for non-vegetarians. On the other hand, although a lack of niacin was observed, the percentage of the recommended dietary allowance of male and female vegetarians was about 90 percent or more. Thus, we came to a conclusion that the diet on which the vegetarian students live was well-balanced overall in terms of nutrient. Let us go on to the physical features of the students.

The average values of the vegetarian students stature were smaller than those of the non-vegetarian students stature in each age group. However, there was no significant difference between the two groups. Likewise, there was no significant difference in weight between the two groups.

Table 3 shows the average value and the standard deviation of points in the C.M.I. The question items here are about physical features. In terms of points totalled, the value of male vegetarians was smaller than that of male non-vegetarians and the value of female non-vegetarians was smaller than that of female vegetarians. There was a significant difference in values in the question items about digestive tract and habit. In questions about habit, the value of female non-vegetarians was significantly smaller than that of female vegetarians. However, further examination revealed that the difference came from the dormitory life they lead, because there was a significant difference of points in questions such as "Do you find it impossible to take a regular rest period each day? and "Do you find it impossible to take regular daily exercise? In questions of digestive tract, the values registered for male vegetarians are significantly smaller than those for male non-vegetarians.

Table 3 - Average Value and Standard Deviation of Points in the C.M.I.
- Male Female
Section Vegetarians Non-veget. Vegetarians Non-veget.
A Eyes and ears 1.02±1.17 1.12±1.55 1.80±1.82 1.40±1.48
B Respiratory system 3.07±2.65 2.75±3.70 3.30±2.87 3.22±3.68
C Cardiovascular system 0.85± 0.99 0.81±1.78 1.82±2.12 1.28±2.00
D Digestive tract 1.70±1.79 3.26±4.13** 3.18±2.19 3.84±3.46
E Musculoskeletal system 0.53±0.93 0.75±1.06 1.08±1.07 1.26±1.38
F Skin. 1.09±1.49 0.83±1.23 1.46±1.59 1.86±2.00
G Nervous system 1.10±1.23 0.98±1.50 2.20±2.47 1.46±2.04
H Genitourinary system 0.51± 0.79 0.33±0.68 2.52±2.19 2.06±1.97
I Fatigability 0.64±0.95 0.58±1.03 1.28±1.47 0.88±1.21
J Frequency of illness 0.49±0.89 0.40±1.01 0.84±1.69 0.68±1.50
I Miscellaneous diseases 0.64±0.78 0.65±0.95 0.90±1.03 0.66±0.93
L Habits 1.15±1.06 1.02±1.24 2.06±1.09 1.34±1.19**
C. I - J 1.98±2.14 1.77±3.23 3.94±4.47 2.90±4.17
A-L Total 12.78±8.54 13.33±15.36 22.44±16.07 20.06±17.97
** P<0.01

See Table 4: Questions Relating to Digestive Tract. There were 28 questions in this section. After close examination, it was revealed that the values for male vegetarians were significantly smaller than those of their non-vegetarian counterparts in 6 question items such as "Are you often sick in your stomach? and that the values for female vegetarians were significantly smaller than those for their non-vegetarian counterparts in 2 questions. It is noticeable that the values for female non-vegetarians were smaller than those for their vegetarian counterparts only in one question "Do you usually feel bloated after eating?

Table 4: Questions Referring to Digestive Tract (%)
- Male Female
Question Veg. Non-veg. Veg Non-veg.
41. Have you lost more than half your teeth? 0 0 0 4.0
42. Are you troubled by bleeding gums? 6.8 10.5 16.0 20.0
43. Have you often had severe toothaches? 1.7 3.5 2.0 8.0
44. Is your tongue usually badly coated 8.5 5.3 10.0 12.0
45. Is your appetite always poor? 5.1 5.3 6.0 10.0
46. Do you usually eat sweets or other food between meals? 18.6 ***64.9 26.0 ***68.0
47. Do you always gulp your food in a hurry? 28.8 21.1 28.0 26.0
48. Do you often suffer from an upset stomach? 3.4 **22.8 14.0 *32.0
49. Do you usually feel bloated after eating? 18.6 21.1 30.0 *12.0
50. Do you usually belch a lot after eating? 16.9 19.3 16.0 16.0
51. Are you often sick to your stomach? 3.4 **21.1 20.0 26.0
52. Do you suffer from indigestion? 0 *10.5 12.0 12.0
53. Do severe pains in the stomach often double you up? 0 7.0 12.0 4.0
54. Do you suffer from constant stomach trouble? 1.7 *14.0 2.0 12.0
55. Does stomach trouble run in your family? 6.8 17.5 20.0 16.0
56. Has a doctor ever said you had stomach ulcers? 0 1.8 0 0
57. Do you suffer from frequent loose bowel movements? 3.4 *19.3 2.0 10.0
58. Have you ever had severe bloody diarrhoea? 0 1.8 0 0
59. Were you ever troubled with intestinal worms? 3.4 3.5 6.0 2.0
60. Do you constantly suffer from had constipation? 0 1.8 10.0 22.0
61. Have you ever had piles (rectal haemorrhoids)? 1.7 1.8 8.0 2.0
62. Have you ever had jaundice (yellow eyes and skin)? 1.7 1.8 2.0 0
63. Have you ever had serious liver or gall bladder trouble? 0 0 0 -
*P<0.05 **P<0.01 ***P<0.001

4. Consideration

A lot of research reports concerning nutrition and health of vegetarians exist in the United States. However, most of them are about adults, and there is comparatively not so many research into vegetarians during the growthperiod. Generally, the scarce amount of protein, vitamin B 12 and iron cause worry about the vegetarian diet.

However, according to the research of Herdinge and Register, both pure-vegetarian diet and lacto-ovo-vegetarian diet quantitatively and qualitatively meet the recommended dietary allowance of protein. In research concerning infants, Dwyer investigated vegetarians from 1 to 8 years old. For the child, the values of stature were smaller than a standard value. They considered that this was due to the inheritance factor of parents stature rather than eating habits factor. They noted that no other particular tendency was observed in respect of physical features. They conclude that there is no problem with a vegetarian diet in respect of health. Sanders reported that pure-vegetarian children from 1 to 6 years old who ate only food of plant origin did not have the feared intake shortage in nutrient of the vitamin B12 and iron.

There are reports that a lacto-ovo-vegetarian diet is a meal enough to meet the recommended dietary allowances of each nutrient such as energy, protein, carbohydrate, vitamins, and minerals.

Likewise, our survey revealed that lacto-ovo-vegetarian students nutricional state is better than that of students of a non-vegetarian diet. No particular tendency was observed in the physical features between the two groups.

Therefore, it can be concluded that the lacto-ovo vegetarian diet has no problem at all as a meal during growth. Moreover, it has been reported that the incidence rate and death rate among adult vegetarians from large intestinal tumours and cancers of the digestive organs are lower than those of people eating a non-vegetarian diet. And this survey shows the subjective symptoms of the stomach and intestines are very few in vegetarians in their early teens.

This is an interesting result from a viewpoint of preventive medicine.

For information contact:
Dr. Mitsuru Kakimoto
c/o Department of Environmental Sciences
Osaka Shin-ai College 2-7-10 Furuichi, Joto-ku, Osaka, 536, Japan
Tel.:+ 816-939-4391, Fax: +816 931 0373
e-mail: office@jpvs.org