Vol.2, No.2, 124-130 (2010)
doi:10.4236/health.2010.22019
SciRes
Copyright © 2010 Openly accessible at http://www.scirp.org/journal/HEALTH/
Health
Effect of past and present lifestyle habits and nutrition
on calcaneal quantitative osteo-sono index in pre- and
post-menopausal females
Masakatsu Nakada1, Shinichi Demura2
1National Defense Academy, Kanagawa, Japan; nakada@nda.ac.jp
2Graduate school of Natural Science & Technology, Kanazawa University, Kanazawa, Japan
Received 4 November 2009; revised 14 December 2009; accepted 17 December 2009.
ABSTRACT
This study is examined the effect of past and
present lifestyle habits and nutrition on the os-
teo-sono assessment index (OSI) in pre- and
post-menopausal females. The subjects were
200 premenopausal females (38.8±10.3years)
and 156 postmenopausal females (59.2±5.9 ye-
ars). BMD (Body mineral density) was estimated
by right-calcaneal OSI using an ultrasonic
transmission method with an AOS-100 device
(ALOKA). The number of postmenopau- sal fe-
males in the close examination and guidance
required groups (80 cases: 51.3 %) (OSI < 2.428)
was significantly higher than that of premeno-
pausal females (44 cases: 22.0 %) (χ233.105:
P<0.000).
In premenopausal females, the proportion of
subjects that had not taken vitamin D in the past
(in junior high school and high school) was
significantly higher in the close examination-
guidance required group (OSI < 2.428) than in
the normal group (OSI 2.428). However, in
postmenopausal females, there was no signifi-
cant difference in past and present lifestyle
habits and nutrition between the close exami-
nation-guidance required group and the normal
group. In premenopausal females, it was deter-
mined that the intake of vitamin D during pu-
berty increased the absorption of calcium sig-
nificantly.
Keywords: Lifestyle and Nutrition Habits, Osteo-Sono
Assessment Index, Pre and Postmenopausal Females
1. INTRODUCTION
The occurrence of osteoporosis with bone-thinning and
brittle bones is high in elderly people [1-3]. The compli-
cations of fractures limit daily activities (ADL) and re-
duce the quality of life (QOL) of the affected individuals
[4-6]. Even when the level of bone loss is below normal
(osteopenia), the risk of fractures is high [5]. Females in
particular are prone to have osteoporosis and should pay
particular attention to the increased risk of a nutritionally
deficient diet [6,7].
On the other hand, the significance of healthy eating
habits in addition to exercise to maintain and increase
BMD has been established [1,8]. In females, bone mass
increases during puberty with skeletal growth and peaks
from the late teens into the twenties. Afterwards, bone
mass is merely maintained from the late thirties to early
forties [5,6]. Bone mass density peaks during youth.
Increased BMD through proper nutrition, exercise, ex-
posure to sun, etc. are all effective measures for pre-
venting osteoporosis [2]. Hence, it will be necessary to
correlate not only present conditions, but also life style
habits during youth. Aging is a significant factor which
affects BMD. However, the effects of lifestyle habits (the
amount of sleep and alcohol consumption, etc.) and nu-
trition on the bone mineral density in females have been
studied specifically in elderly people and young students
[1,2,7,9,10]. However, the effects of lifestyle habits
should be researched for people of a wider age range. On
the other hand, the bone mass of postmenopausal females
decreases markedly with a rapid decline in estrogen levels
[11]. Hence, studies on the BMD in females should be
considered from the onset of menopause. This study
examined the effects of past and present lifestyle habits
and nutrition on the osteo-sono assessment index (OSI) in
pre- and post-menopausal females from age 20 to 70.
2. METHODS
2.1. Subjects
Subjects were 200 premenopausal females (38.8±10.3
years) and 156 postmenopausal females (59.2±5.9 years).
Table 1 shows the number of subjects, and their mean
heights and weights, at each age level. Written informed
consent was obtained from all subjects after a full ex-
M. Nakada et al. / HEALTH 2 (2010) 124-130
SciRes Copyright © 2010 Openly accessible at http://www.scirp.org/journal/HEALTH/
125
planation of the experimental purpose and protocol.
2.2. Measurement of Osteo-Sono
Assessment Index (OSI) and Setting
of OSI Group
BMD was estimated by the right-calcaneus using an
ultrasonic transmission method with an AOS-100 device
(ALOKA). The calcaneal osteo-sono assesment used the
osteo-sono assesment index (OSI: TI×SOS2by calcu-
lating speed of sound (SOS) of ultrasonic transmission in
the calcaneus and the transmission index (TI) as de-
scribed previously [12,13].
The quantitative assessment of bones has generally
been performed by Dual X-ray absorptiometry (DXA
and quantitative ultrasound (QUS) [14]. The DXA can
measure the total body bone mineral density and is main-
ly used for precise measurement after screening tests [5].
The QUS is very practical and safe without the effects of
radiation [5]. The OSI by AOS-100 has high reliability
[14]. Thus, this study used an AOS-100 by QUS. The
Japan Osteoporosis Foundation [5] classified females into
a close examination (OSI < 80% of an average OSI =
2.158), a guidance required group (2.158 OSI < 90%
of an average OSI = 2.428) and a normal group (OSI
2.428) based on an average OSI (OSI = 2.698) of females
between 20 and 44 years old by osteo-sono assessment
criteria. In this study, we combined the former two groups
considering a sample size of each age level and compared
the close examination and guidance required group (OSI
< 2.428 ) with the normal group (OSI 2.428 ).
2.3. Lifestyle and Nutrition Habits
Questionnaire
At present, factors found to be involved in BMD by a
large-scale prospective cohort study (Japanese Popula-
tion-Based Osteoporosis (JPOS) Study) have been ex-
amined [15,16]. These prospective cohort studies have
the advantage of being prospectively able to measure the
predictor, but also require considerable time [17]. The
present study is equivalent to a retrospective cohort study
[17] and while recall bias may affect the conclusions,
useful findings can be identified at an earlier stage.
The study evaluated past and present lifestyle habits
and nutrition by questionnaires. The survey was carried
out just before a measurement of OSI. Naka et al. [2]
selected menopause, regular milk consumption, intensity
of physical exercise, and awareness of eating habits and
physical activity as lifestyle habits. Tomita selected
breakfast habits and regular consumption of milk and
dairy products, fish and shellfish, meat products etc.
during childhood and later years (about 6 – 15 yr) as well
as eating habits. Elgán et al. [18] selected 10 items (diet-
ary habits (i.e. sugar, fat, fiber, and fruit and vegetables),
physical activity, smoking habits, alcohol consumption,
Table 1. Physique of subjects.
NMeanSD Mean SD
20 s44161.05.053.85.5
30 s61158.85.253.47.2
40 s76158.35.253.98.1
50 s104156.64.854.26.5
60 s62154.75.752.87.9
70 s9152.34.252.36.6
Height (cm)Weight (kg)
time spent outdoors etc.) as lifestyle habits. The Japan
Osteoporosis Foundation [5] coffee, milk, dairy products,
fish, meat, soy products, green and yellow vegetables,
and natto as meal and articles of taste items for their
interview sheet. Referring to the above, this study se-
lected the following 9 items to investigate present eating
habits: (1) sleep duration, (2) frequency of alcohol con-
sumption, (3) smoking habits, (4) intervals without meals,
(5) regular consumption of dairy products (milk, cheese,
yogurt, etc.), (6) intake of calcium supplements, (7) in-
take of vitamin D (fish, chicken egg, fungi), (8) intake of
instant food (instant noodles, instant coffee, etc.), and (9)
frequency and length of exposure to sun.
The agreement rates of 9 question items by the test-
retest method of 59 subjects ranged from 0.559 – 0.983.
Their κ coefficients [19] ranged from 0.287 (P=0.010) -
0.890 (P=0.000) and any value was significant. As stated,
the subjects’ past lifestyle habit (in junior high school and
high school) regarding (1) amount of sleep, (2) intervals
without meals, (3) intake of dairy products, (4) intake of
vitamin D, and (5) intake of instant food were among the
above 9 items surveyed.
2.3.2. Data Analysis
Both groups were classified into pre- and
post-menopausal females, cross tabulations of the fre-
quency of past and present lifestyle habits and nutrition
were made, and then independent tests were performed.
When a significant difference emerged, residual analysis
was used. A probability level of 0.05 was indicated sta-
tistical significance.
3. RESULTS
Figure 1 show the results of the osteo-sono assessment
index (OSI). The number of postmenopausal females in
the close examination and guidance required groups (OSI
< 2.428) was significantly higher than that (44 cases:
22.0%) of premenopausal females (χ233.105: P<0.000).
The number of people in the close examination and
guidance required groups increased with age, particularly
in people 50 years and older.
Table 2 (premenopausal females) and Table 3 (post-
menopausal females) show cross tabulations by the fre-
M. Nakada et al. / HEALTH 2 (2010) 124-130
SciRes Copyright © 2010 Openly accessible at http://www.scirp.org/journal/HEALTH/
126
Table 2. Present lifestyle and nutrition habits and the OSI of premenopausal females.
Sleeping timeLess than
6 hours
More than 6
hours - less
than 7 hours
More than 7
hours - less
than 8 hours
More than 8
hours
χ
2
φ
CEGR 10(-1.04) 29(2.39)4
-2.05
)
1
0.967.891 0.048*0.20
Normal48(1.04) 71(-2.39)36
2.05
)
1
-0.96
Alcohol intakeNo 1 - 3 times a
month
1 - 3 times a
wee
k
nearly ever
y
da
y
CEGR 1986107.760.051 0.20
Normal5062 22 21
Smoking NoHave a habitQuit
CEGR 35450.602 0.740.06
Normal 1271612
Skip a mealNoBreakfast LunchSupper
CEGR 355001.664 0.6450.09
Normal 1251824
Intake of dairy prodctsNo 1 - 3 times a
month
4
7 times a
wee
k
CEGR 320210.630.73 0.06
Normal 156279
Intake of Ca supplementNoRarely Continuous
CEGR 33730.564 0.7540.05
Normal 1103114
Intake of vitamin DNo 1 - 3 times a
wee
k
4
7 times a
wee
k
CEGR 525142.200 0.333 0.11
Normal 89454
Intake of instant foodNo 1 - 3 times a
month
More than
once a wee
k
CEGR 514251.816 0.4030.10
Normal 275671
Sunbathing No 1 - 3 times a
wee
k
More than 4
times a week
CEGR 1415151.5570.459 0.09
Normal 396846
Note
CEGR:close examination or guidance required group, *P<0.05,
Result of OSI
Result of OSI
Result of OSI
Result of OSI
Result of OSI
Result of OSI
Result of OSI
Result of OSI
Result of OSI
Number shown in parenthese is the Z score of residual analysis.
13.5
3.5
44.4
19.4
8.7
1.3
1.6
2.3
37.8
18.5
44.4
35.5
39.4
19.7
14.8
11.4
48. 7
78
11.1
45.2
51.9
65.8
83.6
86.4
0%20% 40% 60% 80%100%
Postmenopausal
Premenopausal
70 s
60 s
50 s
40 s
30 s
20 s
close
examination
required
guidance
required
normal
Age and OSI group
Figure 1. Result of osteo-sono assessment index (OSI).
ency of OSI groups and the frequency of present lifestyle habits and nutrition. An independent test showed sig-
M. Nakada et al. / HEALTH 2 (2010) 124-130
SciRes Copyright © 2010 Openly accessible at http://www.scirp.org/journal/HEALTH/
127
nificant differences in the amount of sleep in the
premenopausal group of females. However, the results of
residual analysis showed no significant differences in any
category. In postmenopausal females, there was no sig-
nificant difference in any present lifestyle habits or nu-
trition.
Table 4 (premenopausal females) and Table 5 (post-
menopausal females) show cross tabulations by the fre-
quency of OSI groups and past lifestyle habits and nutri-
tion (in junior high school and high school). An inde-
pendent test showed significant differences in the amount
of sleep and intake of vitamin D in the group of pre-
menopausal females. The results of residual analysis
showed significant differences in the intake of vitamin D,
and there was a higher proportion of subjects taking no
vitamin D in the close examination-guidance required
group (z2.77>2.64p<0.05). In postmenopausal fe-
males, there was no significant difference in past lifestyle
habits and nutrition.
4. DISCUSSION
The Japan Osteoporosis Foundation [5] set the level for
close examination (OSI < 2.158) when using an AOS-100
device (ALOKA) as 0.8 - 1.0 % in people 40-year olds,
and 5.2 -11.4 % in 50-year olds. In this study, they were
respectively 1.3 % and 8.7 %. Hence, the level for close
examination was considered to be standard.
There were no differences in present lifestyle habits
and nutrition by OSI level. Nutrition and eating habits in
addition to exercise habits are important for maintaining
and increasing BMD. Principal minerals for absorption of
calcium are magnesium and Vitamin D [7]. We surveyed
past and present consumption of dairy products and vi-
tamin D excluding magnesium and present intake of
calcium supplements. Lloyd et al. [20] reported that by
increasing daily calcium intake from 80% of the recom-
mended daily allowance to 110% via supplementation
with calcium citrate malate resulted in significant in-
creases in total body and spinal bone density in adoles-
cent girls. The proportion of those test subjects taking no
vitamin D (fish, chicken egg, fungi etc) was higher in the
close examination-guidance required group than in the
normal group. The considerable amount of time that
elderly people spend indoors also decreases Vitamin D
synthesis through the skin in addition to their intake of
vitamin D [5]. Dawson-Hughes et al. [21] examined
during a long-term (3-year) study that the proper intake of
vitamin D with intake of calcium helps reduce the de-
crease of BMD. Intake of sufficient calcium and vitamin
D additionally promotes the absorption of calcium in the
small intestines, maintains calcitriol in the blood, and
prevents an increased parathyroid hormone (PTH) level.
This contributes to a reduction of bone loss [5,21]. The
absorption of calcium is supported by the intake of vita-
min D during puberty (junior high school and high school
age) which increases bone mass with skeletal growth
which may be very important for increasing peak bone
mass.
On the other hand, there was no difference in the past
or present lifestyle habits and nutrition in postmenopausal
females between the close examination and guidance
required groups and the normal group. Bone mass de-
creases with age at the rate of about 3 % a year through a
lack of estrogen even in normal postmenopausal females
[22]. Elderly people may need to increase their daily
requirement of calcium as their intestinal calcium ab-
sorption decreases [23]. Hence, with increasing age and
lack of estrogen, the bone metabolism of postmenopausal
females is largely affected, thus obscuring the effect of
past and present life habits on bone mass changes. In
addition, because of the long interval since puberty for
postmenopausal females, subsequent lifestyle habits
(eating habits and exercise) may have a greater affect on
BMD. Hence, a long-term study should be done consid-
ering the BMD of youth.
This study did not examine the effect of exercise
stimulus. Sanada et al. [24] reportedly showed a signifi-
cant relationship between calcaneal bone strength and the
strength of triceps muscle in postmenopausal females.
Bone mass increases by imposing the load of body mass
on the lumbar spine. Thus, the bone structure of the lower
limbs and thereby the bones of the upper and lower limbs
and spine benefit from the mechanical muscle stimulus
received from twisting, distortion, and towing. Therefore,
BMD is the result of past and present exercise and life-
style habits.
5. SUMMARY
This study examined the effect of past and present life-
style habits and nutrition on OSI in pre- and post-
menopausal females from 20 to 70 years of age.
1) The number of postmenopausal females in the close
examination and guidance required groups (80 cases:
51.3 %) (OSI < 2.428) was significantly higher than that
of premenopausal females (44 cases: 22.0 %) (χ233.105:
P<0.000).
2) In premenopausal females, the number of subjects
who had not taken vitamin D in the past (in junior high
school and high school) was significantly higher in a
close examination-guidance required group (OSI < 2.428)
than in the normal group (OSI 2.428). However, in
postmenopausal females, there was no significant dif-
ference in past and present lifestyle habits and nutrition
between the two groups.
3) In premenopausal females, it was inferred that in-
creased intake of vitamin D during puberty is important to
increase the absorption of calcium.
M. Nakada et al. / HEALTH 2 (2010) 124-130
SciRes Copyright © 2010 Openly accessible at http://www.scirp.org/journal/HEALTH/
128
Table 3. Present lifestyle and nutrition habits and the OSI of postmenopausal females.
ypp
Sleeping timeLess than
6 hours
More than 6
hours - less
than 7 hours
More than 7
hours - less
than 8 hours
More than 8
hours
χ
2
φ
CEGR
22371741.330 0.722 0.09
Normal
17 38192
Alcohol intakeNo 1 - 3 times a
month
1 - 3 times a
week
nearly ever
y
da
CEGR
44168113.907 0.2720.16
Normal
43 8817
Smoking NoHave a habitQuit
CEGR
68741.028 0.5980.08
Normal
63 67
Skip a mealNoBreakfast LunchSupper
CEGR
713301.942 0.584 0.12
Normal
66311
Intake of dairy prodctsNo 1 - 3 times a
month
4
7 times a
week
CEGR
429451.001 0.606 0.08
Normal
22548
Intake of Ca supplementNoRarely Continuous
CEGR
5711102.349 0.309 0.12
Normal
60 511
Intake of vitamin DNo 1 - 3 times a
week
4
7 times a
week
CEGR
740320.012 0.9940.01
Normal
73830
Intake of instant foodNo 1 - 3 times a
month
More than
once a wee
k
CEGR
2124332.787 0.2480.14
Normal
27 2422
Sunbathing No 1 - 3 times a
week
More than 4
times a wee
k
CEGR
1231302.534 0.2820.13
Normal
10 2339
Result of OSI
Result of OSI
Result of OSI
Result of OSI
Result of OSI
Result of OSI
Result of OSI
Result of OSI
Result of OSI
Table 4. Past lifestyle and nutrition and the OSI of premenopausal females.
Sleeping timeLess than
6 hours
More than 6
hours - less
than 7 hours
More than 7
hours - less
than 8 hours
More than 8
hour s
χ
2
φ
CEGR
1(-1.96)10(-0.89)15(0.87)7(2.16)8.4710.037* 0.23
Normal
20(1.96) 48(0.89)46(-0.87) 10(-2.16)
Skip a mealNoBreakfast LunchSupper
CEGR
325001.225 0.2680.08
Normal
112 3100
Intake of dairy prodctsNo 1 - 3 times a
mon th
4
7 times a
week
CEGR
420141.825 0.4020.10
Normal
16 6172
Intake of vitamin DNo 1 - 3 times a
week
4
7 times a
week
CEGR
5(2.77*)22(0.17)8(-1.47)8.712 0.013*0.22
Normal
4(-2.77*) 87(-0.17)51(1.47)
Intake of instant foodNo 1 - 3 times a
mon th
More than
once a week
CEGR
71980.710 0.7010.06
Normal
24 7944
Note
CEGR:close examination or
g
uidance re
q
uired
g
rou
p,
*P<0.05
,
Result of OSI
Result of OSI
Result of OSI
Result of OSI
Result of OSI
Number shown in parentheses is the Z score of the residual analysis
M. Nakada et al. / HEALTH 2 (2010) 124-130
SciRes Copyright © 2010 http://www.scirp.org/journal/HEALTH/Openly accessible at
129
yle and nutrition habits and the OSI of postmenopausal females. Table 5. Past lifest
ypp
Sleeping timeLess than
6 hours
More than 6
hours - less
than 7 hours
More than 7
hours - less
than 8 hours
More than 8
hours χ
2
φ
CEGR 4242390.891 0.8280.09
Normal 6202510
Skip a mealNoBreakfast LunchSupper
CEGR 558202.527 0.2830.14
Normal 52 1100
Intake of dairy prodctsNo 1 - 3 times a
mo n th
4
7 times a
wee
k
CEGR 1539102.937 0.2300.15
Normal 13 3619
Intake of vitamin DNo 1 - 3 times a
mo n th
4
7 times a
wee
k
CEGR 740151.9460.3780.12
Normal 53823
Intake of instant foodNo 1 - 3 times a
mo n th
More than
once a wee
k
CEGR 2527100.203 0.9040.04
Normal 24 2912
Result of OSI
Result of OSI
Result of OSI
Result of OSI
Result of OSI
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