Salt Restriction Affects the Excretions of Minerals (Na, K, Ca, Mg, P and Zn) in the Second Voided Fasting Early Morning Urine.

The plasma concentrations of mineral (sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), phosphorus (P), and zinc (Zn)) are kept within narrow ranges to maintain homeostasis; hence, it is difficult to use them as indicators of nutritional status. We selected the excretion of these minerals in the second voided fasting early morning urine (EMU) as potential indicators of nutritional status. We previously reported that Na restriction caused a negative balance of Ca and Mg. Therefore, Na restriction can cause changes in EMU-minerals. This study aimed to examine the relationship between dietary Na restriction and urinary mineral excretion. The study lasted for 21 d, including 16 d of balance period and 3 d of recovery period. The participants (11 healthy young women) were divided into the Na restriction group (n=5) (NaCl: 6 g/d) and control group (n=6) (NaCl: 12 g/d). The Na restriction group changed to the control diet (NaCl: 12 g/d) during only the recovery period. The EMU-Na, Ca, Mg, P and Zn in the Na restriction group significantly decreased compared with that of the control group. The EMU-Na, K, Ca, Mg, and Zn in the group with NaCl intake of 6 g/d significantly decreased compared with that of the group with NaCl intake of 12 g/d (in the Na restriction group). We conclude that the decrease in excretion of Na, Ca, Mg and Zn in the EMU can lead to Na restriction. This result can serve as basis when considering EMU as an indicator of mineral status.

Dietary Salt (Sodium Chloride) Requirement and Adverse Effects of Salt Restriction in Humans.

Inevitable sodium loss under sodium restriction must not be construed as evidence for the estimated average requirement (EAR) for sodium (Na) in humans. We conducted human mineral balance studies to determine the EAR for some minerals (Na, K, Ca, Mg, P, Zn, Fe, Cu and Mn). Na concentration in arm sweat was low while those of calcium (Ca) and magnesium (Mg) were high, during relatively heavy bicycle-ergometer exercise under relatively low Na intake (100 mmol/d). This suggests that Na was released from the bone, the sole pool of Na, with Ca and Mg. Additionally, the negative balances of Ca and Mg was observed under a relatively low sodium intake (100 mmol/d) even with the sufficient supply and intake of Ca and Mg into human body. Finally, we found no correlation between the Na intake and the Na balance, while the Na-intake was correlated significantly to the balances of K, Ca and Mg. The Na intake necessary to keep the balances of Ca and Mg positive was calculated to be 68 mg/kg body weight/d. To learn the signs and symptoms of low sodium intake, we compared the results of a metabolic study in which subjects consumed diets with 6 g and 12 g salt/d respectively. The blood pressure decreased only with the 6 g/d group. Fecal moisture contents of the 6 g/d group were lower than for the 12 g/d group, suggesting the fecal Na was strongly reabsorbed with water when the dietary Na was insufficienct. Indiscriminate Na restriction may have adverse effects on health.

Daily step count and all-cause mortality in a sample of Japanese elderly people: a cohort study.

BACKGROUND: This study aimed to examine the relationship between pedometer-assessed daily step count and all-cause mortality in a sample of elderly Japanese people. METHODS: Participants included 419 (228 males and 191 females) physically independent, community-dwelling 71-year-old Japanese people. The number of steps per day was measured by a waist-mounted pedometer for seven consecutive days at baseline. Participants were divided into quartiles based on their average number of steps/day (first quartile, < 4503 steps/day; second quartile, 4503-6110 steps/day; third quartile, 6111-7971 steps/day; fourth quartile, > 7972 steps/day) and were followed up over a mean period of 9.8 years (1999-2010) for mortality. RESULTS: Seventy-six participants (18.1%) died during the follow-up period. The hazard ratios (adjusted for sex, body mass index, cigarette smoking, alcohol intake, and medication use) for mortality across the quartiles of daily step count (lowest to highest) were 1.00 (reference), 0.81 (95%CI, 0.43-1.54), 1.26 (95%CI, 0.70-2.26), and 0.46 (95%CI, 0.22-0.96) (P for trend = 0.149). Participants in the highest quartile had a significantly lower risk of death compared with participants in the lowest quartile. CONCLUSION: This study suggested that a high daily step count is associated with a lower risk of all-cause mortality in physically independent Japanese elderly people.

Dentition status and frailty in community-dwelling older adults: A 5-year prospective cohort study.

AIM: To examine the longitudinal association between dentition status and incidence of frailty in older adults. METHODS: The present prospective cohort study included community-dwelling Japanese adults aged 75 years at baseline (n = 322). Dental examinations, biochemical blood examinations, physical performance and anthropometric measurements, and structured questionnaires were carried out at baseline. The presence of ≥20 teeth with nine or more occluding pairs of teeth was defined as functional dentition. Annual follow-up examinations, including physical performance, anthropometric measurements and structured questionnaires, were carried out over a 5-year period to determine the incidence of frailty, defined as three or more of the following five components derived from the Cardiovascular Health Study: weight loss, weakness, slowness, poor energy and low physical activity level. Adjusted hazard ratios of frailty incidence according to dentition status were calculated from Cox proportional hazards regression analyses. RESULTS: At baseline, 118 participants (36.6%) were defined as having functional dentition. During the follow up, 48 participants (14.9%) developed frailty. The adjusted hazard ratio for frailty in participants with functional dentition was 0.50 (95% confidence interval 0.25-0.98) compared with participants without functional dentition, after adjusting for sex, income, education, smoking status, body mass index, serum biomarkers and comorbidities. CONCLUSIONS: Functional dentition was significantly associated with a lower risk of frailty defined by the Cardiovascular Health Study frailty index in older Japanese adults. These results suggest that maintaining healthy and functional dentition into later life is important for frailty prevention. Geriatr Gerontol Int 2018; 18: 256-262.

CD56(dim)CD16(high) and CD56(bright)CD16(-) cell percentages associated with maximum knee extensor strength and incidence of death in elderly.

Physical fitness is an indicator of systemic well-being in humans. Little is known about the role of physical fitness for maintaining systemic health in the elderly. Here, we study elderly subjects to determine the relationships between physical fitness and CD56 and CD16 surface NK cell markers on peripheral blood lymphocytes, as well as to analyze the relationship between the surface markers and incidence of death. We selected 253 independent elderly subjects (122 female; 131 male) who were 79-80 years old. Subjects having a higher proportion of CD56(dim)CD16(high) within CD56(+)CD16(+) cells, or ration of CD56(dim)CD16(high) and CD56(dim)CD16(-) cells had a significant positive correlation with maximum bilateral knee extensor strength/weight (kg) (r = 0.425; P < 0.0001 or r = 0.323; P < 0.0001). In contrast, an increased proportion of CD56(bright)CD16(-) cells within lymphocyte significantly negatively correlated with the maximum bilateral knee extensor strength/weight (kg) (r = -0.290; P = 0.0004); and these subjects had a significantly lower mortality during the 5 years following measurement of death. Therefore, we found that a synergistic effect of the right and left leg muscle strength was associated with proportion of matured NK and NKT cells and induced a low proportion of CD56(bright)CD16(-) cells within lymphocyte. Moreover, the low proportion of CD56(bright)CD16(-) cells was associated with incidence of death. In conclusion, measurements of physical fitness, the proportion of CD56(dim)CD16(high) within CD56(+)CD16(+) cells, the ratio of CD56(dim)CD56(high) and CD56(dim)CD16(-) cells, and the proportion of CD56(bright)C16(-) cells in lymphocytes are important indicators to check elderly health.

Tracking of Pedometer-Determined Physical Activity in Healthy Elderly Japanese People.

BACKGROUND: Tracking refers to the tendency for an individual to maintain their rank within a group over time. This study longitudinally investigated the 8-year tracking of pedometer-determined physical activity among physically independent elderly Japanese people aged 72 to 80 years. METHODS: Steps/day were measured when participants were aged 72 and assessed again after 2, 5, and 8 years. The number of participants with a 2-year follow-up (72 to 74 years) was 177 (101 males, 76 females), with a 5-year follow-up (72 to 77 years) was 183 people (110 males, 73 females), and with an 8-year follow-up (72 to 80 years) was 145 people (91 males, 54 females). Step counts were continuously measured for 1 week in January, April, July, and October during each year of assessment. RESULTS: A high rank correlation coefficient for steps/day exceeding 0.60 was obtained at the 2-, 5- and 8-year follow-up examinations for both males and females. CONCLUSION: This study suggests that the rank within a group of pedometer-determined steps/day remains stable over up to 8 years in healthy Japanese people aged between 72 to 80 years old.

Physical performance and 10-year mortality in a 70-year-old community-dwelling population.

BACKGROUND AND AIMS: Poor physical performance is known to be inversely related to mortality. The purpose of the present study was to determine whether an association between physical performance and 10-year mortality could be extended to a Japanese 70-year-old community-dwelling population, and to compare findings with those found in an octogenarian population. METHODS: Seventy-year-old subjects residing in Niigata city, Japan, participated. Baseline examinations, including a physical performance test of four tests of muscle strength, one test of balance, and one test of agility, were carried out in June 1998 for 600 participants, and these individuals were then followed for 10 years. RESULTS: During the 10-year follow up, 80 subjects died. Cox regression analysis with adjustment for confounding factors showed that high scores in muscle strength tests for lower extremities, such as single-leg and double-leg extensor strength and isokinetic leg extensor power, were found to be related to decreases in total cause mortality. CONCLUSIONS: In an elderly 70-year-old Japanese community-dwelling population, poor muscle strength was found to be an independent predictor of total mortality. Together with our previous findings in an 80-year-old population, the association between poor strength and high mortality may have effects at 70 but not 80 years of age.

Estimated equilibrated dietary intakes for nine minerals (Na, K, Ca, Mg, P, Fe, Zn, Cu, and Mn) adjusted by mineral balance medians in young Japanese females.

The present study sought to determine estimated equilibrated dietary intakes (EEDIs) for nine essential minerals: sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), phosphorus (P), iron (Fe), zinc (Zn), copper (Cu), and manganese (Mn), using data from 17 human mineral balance studies conducted from 1986 to 2007 (subjects=178). Among these studies, two used male subjects, two subjected some or all subjects to sodium restriction, and one study utilized a low protein diet; these subjects were not included in the present analysis. Consequently, data from 13 studies of young female subjects (n=131) consuming a standard diet were selected. Balance distribution medians for six of the minerals (Na, K, Mg, Fe, Zn and Cu) were positive, so the data were adjusted to set the medians of the balances to zero. Medians for the other minerals (Ca, P and Mn) were close to zero and were not adjusted. Intake and balance for each mineral were divided by body weight (BW), lean body mass (LBM), and standard body weight (SBW), which was calculated using height and standard body mass index (BMI=22), and EEDIs were calculated as the intercept of a simple regression equation. When relationships between intake and balance of a mineral were not significant in the regression equation, a significant regression equation comparing intake and balance of another mineral was used to calculate the intercept. Significant simple regression equations were not obtained from any of the three parameters of Na or Zn, or for two of the parameters of P; thus, K, Fe and Ca balances were used to determine the intercepts for Na, Zn and P, respectively. EEDIs for the minerals were: Na (67.9, 89.0, 62.5), K (39.5, 53.5, 37.4), Ca (11.0, 14.4, 10.1), Mg (4.18, 5.51, 3.86), P (18.7, 24.6, 17.3) (mg/kg BW/d, mg/kg LBM/d, mg/kg SBW/d), Fe (180, 237, 165), Zn (181, 241, 166), [corrected] Cu (32.3, 42.6, 29.7), [corrected] Mn (55.1, 72.1, 50.7) (µg/kg BW/d, µg/kg LBM/d, µg/kg SBW/d), respectively. These values are nearly identical to the mean dietary intakes.

Equilibrium energy intake estimated by dietary energy intake and body weight changes in young Japanese females.

To determine the energy intake (EI) required to maintain body weight (equilibrium energy intake: EEI), we investigated the relationship between calculated energy intake and body weight changes in female subjects participating in 14 human balance studies (n=149) conducted at the National Institute of Health and Nutrition (Tokyo). In four and a half studies (n=43), sweat was collected from the arm to estimate loss of minerals through sweating during exercise on a bicycle ergometer; these subjects were classified in the exercise group (Ex G). In nine and a half experiments (n=106) subjects did not exercise, and were classified in the sedentary group (Sed G). The relationship between dietary energy intake (EI) and body weight (BW) changes (ΔBW) was analyzed and divided by four variables: body weight (BW), lean body mass (LBM), standard body weight (SBW), and body surface area (BSA). Equilibrium energy intake (EEI) and 95% confidence interval (CI) for EEI in Ex G were 34.3 and 32.8-35.9 kcal/kg BW/d, 32.0 and 30.8-33.1 kcal/kg SBW/d, 46.3 and 44.2-48.5 kcal/kg LBW/d, and 1,200 and 1,170-1,240 kcal/m(2) BSA/d, respectively. EEI and 95% CI for EEI in Sed G were 34.5 and 33.9-35.1 kcal/kg BW/d, 31.4 and 30.9-32.0 kcal/kg SBW/d, 44.9 and 44.1-45.8 kcal/kg LBM/d, and 1,200 and 1,180-1,210 kcal/m2 BSA/d, respectively. EEIs obtained in this study are 3 to 5% higher than estimated energy requirement (EER) for Japanese. In five out of six analyses, EER in a population (female, 18-29 y, physical activity level: 1.50) was under 95% CI of EEI obtained in this study.

Natural S-equol decreases bone resorption in postmenopausal, non-equol-producing Japanese women: a pilot randomized, placebo-controlled trial.

OBJECTIVE: Equol is a metabolite of the isoflavone daidzein and may play a critical role in preventing bone loss by soy isoflavones in postmenopausal women. However, results from clinical trials have not been published. The aim of this study was to investigate the effects of equol on bone metabolism and serum sex and thyroid hormone levels in postmenopausal Japanese women. METHODS: We performed a 1-year double-blind, randomized, placebo-controlled trial with natural S-equol supplements for 93 non-equol-producing menopausal Japanese women. Participants were randomly assigned to four groups receiving the following: placebo, 2 mg of equol supplement per day, 6 mg of equol supplement per day, and 10 mg of equol supplement per day. RESULTS: Equol intervention increased equol concentrations in serum and urine in a dose-dependent manner. Urinary deoxypyridinoline was significantly decreased, with a -23.94% change in the group that received 10 mg of equol supplement per day as compared with a -2.87% change in the group that received placebo after 12 months of intervention (P = 0.020). Thus, 10 mg/day of equol supplement markedly inhibited bone resorption. Treatment with 10 mg/day of equol prevented a decrease in bone mineral density in the entire body in postmenopausal women after 12 months. Sex and thyroid hormone concentrations in serum did not differ among the four groups after intervention. CONCLUSIONS: These findings suggest that 10 mg/day of natural S-equol supplementation contributes to bone health in non-equol-producing postmenopausal women without adverse effects.

Influence of dental occlusion on physical fitness decline in a healthy Japanese elderly population.

The aim of this study was to clarify the relationship between dental occlusion and physical fitness by a longitudinal survey. A sample of 348 subjects (171 men and 177 women) aged 71 was investigated by Eichner index (EI) as an occlusal condition (Class A: no loss; Class B: partial loss; Class C: complete loss) and five types of physical fitness tests and were re-examined 8 years later. The upper 50% were sampled to analyze the correlation between each physical fitness decline and the EI at the baseline by logistic regression models. Logistic regression analyses revealed that leg extensor power (Class B vs. Class A; odds ratio=OR=4.61, p=0.010) and one-leg standing time with eyes open (Class C vs. Class A; OR=4.27, p=0.031) showed significant correlations with the EI at the baseline. In this study, partial or complete loss of occlusion was associated with a decline in leg extensor power or a decrease in one-leg standing time with eyes open. These findings suggest that maintenance of dental occlusion may prevent a decrease in activities of daily living in the elderly.

Average daily intake of phosphorus in 3- to 5-year-old Japanese children as assessed by the duplicate-diet technique.

The present study aimed to determine whether there is excessive mean daily intake of phosphorus in 3- to 5-year-old Japanese children and to ascertain relationships between phosphorus intake and various food and beverage groups. Subjects comprised of 90 children, with 15 boys and 15 girls in each age group from 3 to 5 years. The duplicate-diet technique was used to ascertain total dietary intake, including snacks and beverages over a 24-h period on 3 separate days from summer 1999 to winter 2000. After wet ashing food samples, phosphorus was quantified by colourimetry using a spectrophotometer. Median and 25th-75th percentile daily phosphorus intake for 3- to 5-year-old Japanese children was 674 mg (534-890 mg), and phosphorus intake correlated with the intake of many food groups and was closely correlated with total daily intake of food and beverage (rs=0.64). In addition, phosphorus intake correlated with the intake of magnesium and calcium (rs>=0.6, p<0.001). When assessed based on dietary reference intakes for the US, maximum intake did not exceed the tolerable upper intake level in any of the young children, but phosphorus intake was not more than the estimated average requirement (EAR) in 4.4% of subjects, which exceeded the target of 2.5% for the US EAR. We concluded that there is a risk of insufficient phosphorous intake, rather than excessive intake, for 4.4% of 3- to 5-year-old Japanese children.

Effect of low dose vitamin K2 (MK-4) supplementation on bio-indices in postmenopausal Japanese women.

It has been reported that treatment with a pharmacological dose (45 mg/d) of menaquinone-4 (MK-4) prevents bone loss in postmenopausal women. However, it is not known whether supplementation with low dose MK-4 has beneficial effects on bone metabolism in healthy women. The aim of this study is to examine the effects of the supplementation of 1.5 mg/d MK-4 for 4 wk on bone and lipid metabolism in healthy postmenopausal Japanese women. The study was performed as a randomized double blind placebo-controlled trial. The participants aged 53-65 y were randomly assigned to 2 groups and supplemented with 1.5 mg/d of MK-4 or a placebo for 4 wk (n=20 for each group). The most marked effects of MK-4 intake were observed on serum osteocalcin (OC) concentrations. Serum undercarboxylated OC (ucOC) concentration decreased, and the gamma-carboxylated OC (GlaOC) and GlaOC/GlaOC+ucOC ratio that indicates the degree of OC gamma-carboxylation increased significantly at 2 and 4 wk compared with that at baseline in the MK-4 group. The serum ucOC and GlaOC concentrations in the MK-4 group were significantly different from those in the placebo group at 2 wk. These results suggest that supplementation with 1.5 mg/d MK-4 accelerated the degree of OC gamma-carboxylation. The concentrations of serum lipids and other indices were not different between the groups at either intervention period. Thus, the additional intake of MK-4 might be beneficial in the maintenance of bone health in postmenopausal Japanese women.

Intra- and inter-individual variations of blood and urinary water-soluble vitamins in Japanese young adults consuming a semi-purified diet for 7 days.

We have previously reported the levels of water-soluble vitamins in the blood and urine of Japanese young adults. In the present paper, to assess the variations in these water-soluble vitamin markers during the above experiment, we comprehensively determined the intra- and inter-individual variations of blood and urinary water-soluble vitamins to exactly the same amount of water-soluble vitamin intakes in the same experiment. The blood samples before breakfast and the 24-h urine samples were periodically collected from Japanese college male (n=10) and female (n=10) students consuming a semi-purified diet with water-soluble vitamins based on Japanese Dietary Reference Intakes for 7 d, and the intra- and inter-individual variations of blood and urinary water-soluble vitamins or their metabolites in blood and urine samples after adaptation were calculated. Although urinary excretion of vitamin B(12) and vitamin C showed high intra-individual variations in both males and females, other urinary vitamins and all blood vitamins showed less than 20% of within-subject coefficients of variance in either male or female. Those showing more than 20% of between-subject coefficients of variances in both male and female were blood vitamin B(6), vitamin B(12) and folate levels, and urinary vitamin B(1), vitamin B(2), vitamin B(12), nicotinamide metabolites, pantothenic acid, biotin and vitamin C. These results showed that oral administration of constant of water-soluble vitamins generally decreased intra-individual variation, while individual differences in urinary vitamin excretion were observed.

Calcium, magnesium, potassium and sodium intakes in Japanese children aged 3 to 5 years.

The present study aimed to evaluate in preschool children the intakes of Ca, Mg that possibly affect health and tooth formation and the intakes of K and Na that may affect lifestyle-related diseases. Information on dietary intake was collected from 90 preschool children (15 boys and 15 girls each in the 3-, 4- and 5-year old groups) on 3 separate days in the school fiscal year 1999 (April 1999 to March 2000) by the duplicate-diet technique. The Ca, Mg, K, and Na concentrations were determined by atomic absorption spectrometry using wet-ashed samples. The medians of mean daily intakes of Ca, Mg, K and Na in 3- to 5-year-old children were 432 mg, 110 mg, 1.18 g and 1.60 g, respectively, and no significant differences with regard to gender were observed. Seasonal varia-tion of intake was seen for each mineral. Calcium intake in most preschool children did not meet adequate intake (AI), probably due to low intakes of milk and dairy products in Japan. Magnesium intake was below the estimated average requirement (EAR) in 13.3% of the subjects, while the K intake met the AI. Sodium intake in a quarter of preschool children exceeded the tentative dietary goal. We concluded that in Japanese children aged 3-5 years; Ca intake is low, Na intake is high, and K intake is adequate, but some children could be at risk for Mg deficiency.

Iron, zinc, manganese and copper intakes in Japanese children aged 3 to 5 years.

This study aimed to measure and evaluate the intakes for the four trace elements of Fe, Zn, Mn, and Cu in 3- to 5-y-old Japanese preschool children. The study group consisted of a total of 90 3- to 5-y-old children living in Yokkaichi, Mie, Japan. Diet samples were collected by the duplicate-portion technique on 3 d at three different seasons between summer in 1999 and winter in 2000. The medians of annual mean daily intakes (25th-75th percentile) of Fe, Zn, Mn, and Cu in the 3- to 5-y-old children were 3.1 mg (2.4 to 3.6), 4.0 mg (3.4 to 4.7), 1.3 mg (1.1 to 1.6), and 0.45 mg (0.35 to 0.56), respectively. The annual mean value of the total daily diet intake had significant correlations with the Fe, Zn, Mn and Cu intakes (Spearman's r=0.55, 0.67, 0.58, and 0.55, respectively; p<0.001 for all). There were significant correlations between each mineral intake. The Zn and Mn intakes had differences among ages (p=0.003 and 0.005, respectively) and the Zn intake significantly differed between boys and girls (p=0.031). The proportion of subjects whose Mn intake was the AI or less was 82%, and the proportions of subjects whose Fe, Zn, and Cu intakes were the estimated average requirements (EARs) or less were 72, 83, and 13%, respectively. Many Japanese children are deficient in Fe and Zn compared with the dietary reference intakes (DRIs). However, data in a balance study examining intakes and excretion of trace minerals are insufficient in children and DRIs for trace elements may change in future.

Characteristics of urine sodium and potassium after oral ingestion of solutions containing sodium and potassium which is isotonic to the physiological saline--a quantitative study.

The effects of orally ingesting 500 mL of four kinds of test solutions that were isotonic to physiological saline (i.e., containing sodium (Na) and potassium (K) as chloride with Na/K molar ratios of 1, 2, 3 and 4) on urine flow, Na and K excretions from Japanese male students were investigated. The subjects assembled at the National Institute of Nutrition the day before the oral ingestions, which were conducted three times for each subject. They were permitted to eat freely until 8:00 pm, and then the intake of food and drinks except tap water was prohibited until 10:00 pm. After that, no food or drinks except the test solution used, were permitted to be ingested until the end of the final collection of urine. Subjects were woken up at 7:00 am the next morning, at which time they emptied their bladder. At 8:00 am, after sampling control urine before ingestion, they ingested 500 mL of water, the physiological saline or one of the test solutions. Urine was collected every 30 min for 4 h after ingestion. Urine flow was significantly higher for those who drank solutions Na/ K = 1 and 2 than those who drank the saline (paired-t test), but that for those who drank solutions Na/K = 3 and 4 was not significantly higher. For those who drank solution Na/ k=2, urine Na was significantly higher than that of those who drank the saline 30 to 60 min after ingestion. An increase in urine flow after K ingestion may be an essential factor for K-induced Na uresis.

Molybdenum balance in healthy young Japanese women.

The absorption and balance of molybdenum (Mo) were examined in 43 healthy young Japanese women in four metabolic studies performed once a year from 2001 to 2004. In each year, an 18-d metabolic study, including two successive balance study sessions of 4 d, was designed and four kinds of dietary menus were supplied to the subjects periodically. Since the protein sources of the menus were specified in 2001-2003, and soybean products were poor in 2001 and 2002 and rich in the 2003, Mo intake in 2001 and 2002 was about 150microg/d while that in 2003 reached 318microg/d. In 2004, the protein sources were not specified and Mo intake was 217microg/d. This range of Mo intake overlapped that in the Japanese population. When the results of the four studies were pooled, Mo balance was calculated as 0.09+/-0.37microg/d/kg (mean+/-SD), and no significant relationship (r=0.142) was observed between the intake and balance. Between the apparent absorption (Y) and the intake (X), a significant (r=0.988, p<0.001) positive linear regression (Y=0.927X-0.523) was observed. Similarly, a significant (r=0.960, p<0.001) positive linear regression was observed between Mo intake and urinary excretion. These results indicate that more than 90% of Mo contained in a routine dietary menu is absorbed, most of Mo absorbed is excreted in urine, and Mo balance is in equilibrium in the general Japanese population.

Effects of a 21 day metabolic study on serum opsonic activity in female college students, assessed by a chemiluminescence technique.

A metabolic study to evaluate nutritional balance, in which subjects have to eat all the foods supplied and maintain a set schedule, is thought to be stressful for the subjects. The effects of stress on the immune system have been studied extensively. However, there are no studies of non-specific immunological changes during a metabolic study. Serum opsonic activity (SOA) is a direct and suitable indicator of non-specific humoral immunity. In this study, we used luminol-dependent chemiluminescence (LmCL) to measure reactive oxygen species (ROS) generation from pooled human neutrophils as an indicator of SOA. We also measured serum immunoglobulin levels and plasma myeloperoxidase (MPO) activity. Eleven female college students took part in this 21 day metabolic study after giving their written informed consent. The results obtained suggest that the metabolic study has almost no effect on immunoglobulin levels. According to MPO levels, neutrophils in vivo may be deactivated to some minor extent. In contrast to these results, peak time (PT) and peak height (PH) of LmCL were changed significantly during the metabolic study. In conclusion, SOA increased during the 21 day metabolic study. There was no significant correlation between SOA and serum immunoglobulin levels on any of the study days.

Moisture and mineral content of human feces--high fecal moisture is associated with increased sodium and decreased potassium content--.

BACKGROUND: The origin of moisture in diarrhea feces is unknown but may represent the unabsorbed part of intestinal contents or alternatively, body fluid excreted into the digestive canal. If the latter mechanism contributes to moisture in the feces, active transport of water (H2O) associated with ion exchange channels may be involved. OBJECTIVE: To investigate this possibility we measured the content of moisture and minerals (sodium [Na], potassium [K], calcium [Ca], magnesium [Mg], phosphorus [P], zinc [Zn], iron [Fe], copper [Cu] and manganese [Mn]) in feces collected during a 12-d metabolic study on 11 young Japanese female students. DESIGN: The study was carried out as part of a human mineral balance study. The same quantity of food was supplied to each of the subjects throughout the study without consideration of body weight. Fecal specimens were collected throughout the study and were separated into those originating from the diet during the balance period based on the appearance of the ingested colored marker in the feces. RESULTS: The moisture content of the feces ranged between 53 and 92%. Na content in the feces was low and stable when the moisture content was below 80%, whereas it increased up to serum levels when the moisture content increased above 80%. On the other hand, K content increased when compared to dry matter base. However, when comparing concentration/g moisture, K content increased when moisture was below 70%, but decreased when this rose above 70%.