Effect of supplementation with flaxseed oil and different doses of fish oil for 2 weeks on plasma phosphatidylcholine fatty acids in young women.

BACKGROUND/OBJECTIVES: Although assumed, it remains unclear that fatty acid (FA) biomarkers of n-3 long-chain PUFA reflect wide ranges of intake. However, to be utilised as biomarkers, to predict dietary intake, dose-response curves that cover a spectrum of intakes are required. The aim of the study was to investigate whether the FA composition of plasma phosphatidylcholine (PC) is a sensitive biomarker of n-3 FAs from fish oil, across a range of supplementation doses, and alpha-linolenic acid (ALA) supplementation, in young, healthy women. SUBJECTS/METHODS: A total of 303 young women were randomised to intakes ranging between 0.33 and 4.50 g EPA+DHA/day from fish oil (not all doses used in each year) or flaxseed oil (5.90-6.60 g/d) daily for 14 days in a series of trials, over 5 years. Fasting blood was collected at baseline (day 0) and day 14 and plasma PC FA composition, total and HDL-cholesterol and triglyceride concentrations measured. RESULTS: Fourteen days supplementation with fish oil significantly (P < 0.01) increased, in a dose-dependent fashion, plasma PC EPA, DPA and DHA at all doses except 1 and 3 mL/day. For the combined group of women who consumed any fish oil there was a 16% (P < 0.01) decrease in plasma triacylglycerol concentrations after 14 days supplementation. Flaxseed oil supplementation for 14 day resulted in significant (P < 0.01) increases in ALA, EPA and DPA, whilst DHA remained unchanged. CONCLUSION: Our data demonstrate plasma PC is a sensitive biomarker of n-3 FA intake and reflects changes within 14 days across a range of intakes.

Vitamin D3 Supplementation Does Not Improve Sprint Performance in Professional Rugby Players: A Randomized, Placebo-Controlled, Double-Blind Intervention Study.

Vitamin D insufficiency is common in athletes and may lower physical performance. Many cross-sectional studies associate vitamin D status with physical performance in athletes; however, there have been few prospective randomized controlled trials with adequate statistical power to test this relationship, and none in the southern hemisphere. Thus, a prospective double-blind, randomized, placebo-controlled intervention trial was conducted involving 57 professional rugby union players in New Zealand. Participants were randomized to receive 50,000 IU of cholecalciferol (equivalent to 3,570 IU/day) or placebo once every two weeks over 11-12 weeks. Serum 25(OH)D concentrations and physical performance were measured at baseline, weeks 5-6, and weeks 11-12. Mean (SD) serum 25(OH)D concentrations for all participants at baseline was 94 (18) nmol/L, with all players above 50 nmol/L. Vitamin D supplementation significantly increased serum 25(OH)D concentrations compared to placebo, with a 32 nmol/L difference between groups at 11-12 weeks (95% CI, 26-38; p < 0.001). Performance in five of the six tests at study completion, including the primary outcome variable of 30-m sprint time, did not differ between the vitamin D supplemented and placebo groups (p > 0.05). Performance on the weighted reverse-grip chin up was significantly higher in players receiving vitamin D compared with placebo, by 5.5 kg (95% CI, 2.0-8.9; p = 0.002). Despite significantly improving vitamin D status in these professional rugby union players, vitamin D supplementation had little impact on physical performance outcomes. Thus, it is unlikely that vitamin D supplementation is an ergogenic aid in this group of athletes.

Association of cord blood vitamin D with early childhood growth and neurodevelopment.

AIM: The association between fetal vitamin D [25-hydroxyvitamin D (25(OH)D)] exposure and early child growth and neurodevelopment is controversial. The aim of this study was to investigate the association between cord blood 25(OH)D and birth size, childhood growth and neurodevelopment. METHODS: Cord blood samples from 1040 Australian women enrolled in a randomised trial of docosahexaenoic acid (DHA) supplementation during pregnancy were analysed for 25(OH)D using mass spectroscopy. Infant length, weight and head circumference were measured at delivery. A sub-sample of 337 infants with cord blood samples were selected for growth and neurodevelopment assessment at 18 months and 4 years of age. Associations between standardised 25(OH)D and outcomes were assessed, taking into account DHA treatment, social and demographic variables. RESULTS: Standardised 25(OH)D in cord blood was not associated with length, weight or head circumference at birth, 18 months or 4 years of age. 25(OH)D was not associated with cognitive, motor, social-emotional or adaptive behaviour scores at 18 months, or cognitive score at 4 years of age. A 10 nmol/L increase in cord blood 25(OH)D was associated with a modest increase in average Language scores of 0.60 points at 18 months (adjusted 95% CI 0.04-1.17, P = .04) and 0.68 points at 4 years (adjusted 95% CI 0.07-1.29, P = .03) of age. CONCLUSIONS: Cord blood vitamin D was modestly, positively associated with language development in early childhood in our sample, although the magnitude of the association was small. Randomised controlled trials are needed to confirm a causal association and establish the potential clinical significance of the relationship between vitamin D status and language development.

Serum and erythrocyte folate status of New Zealand women of childbearing age following a countrywide voluntary programme by the baking industry to fortify bread with folic acid.

OBJECTIVE: To estimate the folate status of New Zealand women of childbearing age following the introduction, in 2010, of a new voluntary folic acid fortification of bread programme. DESIGN: The 2011 Folate and Women's Health Survey was a cross-sectional survey of women aged 18-44 years carried out in 2011. The survey used a stratified random sampling technique with the Electoral Roll as the sampling frame. Women were asked about consumption of folic-acid-fortified breads and breakfast cereals in a telephone interview. During a clinic visit, blood was collected for serum and erythrocyte folate measurement by microbiological assay. SETTING: A North Island (Wellington) and South Island (Dunedin) city centre in New Zealand. SUBJECTS: Two hundred and eighty-eight women, of whom 278 completed a clinic visit. RESULTS: Geometric mean serum and erythrocyte folate concentrations were 30 nmol/l and 996 nmol/l, respectively. Folate status was 30-40 % higher compared with women of childbearing age sampled as part of a national survey in 2008/09, prior to the introduction of the voluntary folic acid bread fortification programme. In the 2011 Folate and Women's Health Survey, reported consumption of fortified bread and fortified breakfast cereal in the past week was associated with 25 % (P=0·01) and 15 % (P=0·04) higher serum folate concentrations, respectively. CONCLUSIONS: Serum and erythrocyte folate concentrations have increased in New Zealand women of childbearing age since the number of folic-acid-fortified breads was increased voluntarily in 2010. Consumption of fortified breads and breakfast cereals was associated with a higher folate status.

Estimation of serum and erythrocyte folate concentrations in the New Zealand adult population within a background of voluntary folic acid fortification.

National data on the blood folate status of New Zealand adults is lacking. The objective of this study was to describe the blood folate status and examine the predictors of blood folate status in a national sample of adults from New Zealand, a country with voluntary folic acid fortification. The 2008/09 New Zealand Adult Nutrition Survey was a nationwide multistage systematic random cross-sectional survey. Serum and erythrocyte folate concentrations were measured by microbiologic assay. The survey included 4721 participants aged ≥15 y, 3359 of whom provided a nonfasting blood sample. Biochemical folate status was measured in 3277 participants. The median serum and erythrocyte folate concentrations were 23 and 809 nmol/L, respectively. The prevalence of biochemical folate deficiency, defined as plasma folate <6.8 nmol/L or erythrocyte folate <305 nmol/L, was 2%. Having breakfast daily compared with never eating breakfast was associated with 53% higher serum and 25% higher erythrocyte folate concentrations; consumers of fortified yeast extract spread had 17% higher serum and 14% higher erythrocyte folate concentrations than nonconsumers; daily users of folate-containing supplements compared with nonusers had 48% higher serum and 28% higher erythrocyte folate concentrations. The prevalence of biochemical folate deficiency in New Zealand adults is low. Participants who ate breakfast more frequently, consumed folate-fortified yeast, or used a daily folate supplement had higher blood folate concentrations.

Influence of the glutathione peroxidase 1 Pro200Leu polymorphism on the response of glutathione peroxidase activity to selenium supplementation: a randomized controlled trial.

BACKGROUND: A genetic variant at codon 200 (Pro200Leu) of the gene encoding for glutathione peroxidase 1 (GPx1), a selenium-dependent enzyme, is associated with lower enzyme activity; however, the evidence is limited to in vitro and observational studies. OBJECTIVE: The objective was to determine whether the GPx1 Pro200Leu genetic variants modify the response of whole-blood glutathione peroxidase (GPx) activity to selenium supplementation in patients with coronary artery disease in New Zealand. DESIGN: The results from 2 parallel-design, double-blind trials were combined. Participants were randomly assigned to receive a daily supplement of 100 µg Se as l-selenomethionine (n = 129) or placebo (n = 126) for 12 wk. Plasma selenium and whole-blood GPx activity were measured at baseline and at week 12. Participants were genotyped for the GPx1 Pro200Leu polymorphism. RESULTS: Selenium supplementation increased whole-blood GPx activity by 5 (95% CI: 4, 7) U/g hemoglobin (P < 0.001); however, the magnitude of the increase did not differ by genotype (P = 0.165 for treatment-by-genotype interaction). In an exploratory analysis, a significant nutrient-gene interaction was apparent when baseline plasma selenium concentrations were included in the regression model (P = 0.006 for treatment-by-genotype × baseline selenium concentration interaction). Increases in GPx activity were 2-fold higher in Pro homozygotes than in participants carrying a Leu allele when baseline selenium concentrations were ≤1.15 µmol/L (P < 0.05). CONCLUSIONS: These results indicate that GPx1 Pro200Leu variants do not substantially modify the response of whole-blood GPx to selenium supplementation in individuals with relatively high plasma selenium concentrations. A nutrient-gene interaction was observed when the baseline selenium concentration was low, but this requires independent confirmation. This trial was registered at www.actr.org.au as ACTRN12605000412639 and ACTRN12606000197538.

Differences in erythrocyte folate concentrations in older adults reached steady-state within one year in a two-year, controlled, 1 mg/d folate supplementation trial.

Daily supplementation with folate increases erythrocyte folate concentrations; however, the time to reach steady-state concentrations has not been empirically demonstrated. Previous predictions of time to steady state or time to 90% steady-state concentration, based on modeling changes in erythrocyte folate during short-term trials, range widely from 40 to 86 wk. We sought to determine the time to steady-state erythrocyte folate concentrations following the initiation of daily folate supplementation using data collected from a 2-y, double-blind, placebo-controlled, randomized trial involving 276 participants aged 65 y or older. The daily supplement contained 1 mg of folate. Erythrocyte folate concentrations were measured, using a microbiological assay, at baseline and at 6, 12, 18, and 24 mo. The mean plasma and erythrocyte folate concentrations in the folate-supplemented group were higher than in the placebo group at 6, 12, 18, and 24 mo (P < 0.001). Adjusted for baseline differences, the difference in erythrocyte folate concentrations between the folate and placebo group at 6 mo was 1.78 µmol/L (95% CI: 1.62-1.95 µmol/L). The difference increased significantly to 2.02 µmol/L (95% CI: 1.85-2.18 µmol/L) at 12 mo. This difference (between the folate and placebo groups) did not significantly change after a further year of folate supplementation; at 18 mo, it was 2.09 µmol/L (95% CI: 1.92-2.27 µmol/L) and at 24 mo it was 1.98 µmol/L (95% CI: 1.18-2.15 µmol/L). Twelve months of daily folate supplementation with 1 mg is sufficient time to cause erythrocyte folate concentrations to reach a new steady state.

Reliable change indices for the ruff 2 and 7 selective attention test in older adults.

The assessment of suspected dementia often involves the analysis of change scores from neuropsychological tests administered on two occasions. Frequently, no information is available to allow the significance of a change to be evaluated. Our aim was to prepare data useful for estimating the statistical significance of retest changes for persons older than the age of 65 on the Ruff 2 and 7 Selective Attention Test, one of the few paper-and-pencil tests of attention available to the clinician. The sample tested was composed of 234 healthy adults taking part in a randomized double-blind trial of the effect on cognitive performance of lowering homocysteine using dietary supplements, during which no treatment effects were detected. The test was found to be sensitive to the effects of aging and was well tolerated by our sample of older adults. Retest reliability for the speed of visual search for digit targets (2 and 7) under both the same category (other digits) and different category (letter) distracter conditions was high, and the practice effects during a 12-month period were substantial. Test-retest data with a 1-year interval were used to estimate reliability coefficients and to calculate Reliable Change indices useful for evaluating persons with suspected dementia. The rate of decline in search speed as a function of age was the same for both distraction conditions, suggesting that older persons used a controlled serial search process for targets in both conditions of this test.

The effect of increasing consumption of pulses and wholegrains in obese people: a randomized controlled trial.

BACKGROUND: Wholegrain intake is inversely related to weight gain over time, but little information is available on the role of pulses in weight control. OBJECTIVE: To compare weight loss, metabolic outcomes, and nutrient intakes in obese people assigned to a diet rich in pulses and wholegrains or a control diet. METHODS: Randomized controlled study of 18 months with 113 volunteers (body mass index [BMI] ≥ 28 kg/m(2)). Diets were based on guidelines published by the National Heart Foundation of New Zealand. The intervention group was advised to consume 2 serves of pulses and 4 serves of wholegrain foods per day as substitutions for more refined carbohydrates. RESULTS: Fiber intakes were higher, intakes of several vitamins and minerals were better maintained, and dietary glycemic index was lower in the intervention compared with the control group. Mean (standard error [SE]) weight loss at 6 months was 6.0 (0.7) kg and 6.3 (0.6) kg in the control and intervention groups, respectively, and was not different between groups (p > 0.05). Blood pressure, triglycerides, and glycemic load were lowered in both groups compared with baseline. Waist circumference was decreased at 18 months in the intervention compared with the control group (-2.8 cm; 95% confidence interval [CI]: -0.4, -5.1). CONCLUSIONS: Incorporation of pulses and wholegrain foods into a weight loss program resulted in a greater reduction in waist circumference compared with the group consuming a control diet, although no difference in weight loss was noted between groups. Retention of several nutrients was better with the pulse and wholegrain diet.

Milk fortified with the current adequate intake for vitamin D (5 microg) increases serum 25-hydroxyvitamin D compared to control milk but is not sufficient to prevent a seasonal decline in young women.

Low vitamin D status in women of childbearing age may have implications for health. Vitamin D status of New Zealanders (NZ), based on low serum 25-hydroxyvitamin D (25OHD) is suboptimal. Vitamin D status may be improved with supplements and/or fortified foods. Recently an Adequate Intake (AI) for Australia and NZ was set at 5 microg/d vitamin D. We aimed to determine the effect of daily consumption of milk powder fortified with 5 microg vitamin D3 on serum 25OHD concentration over 12 wks. 73 non-pregnant women (18 - 47 y) living in Dunedin, NZ (46 degrees S) were randomised to receive either unfortified (control) or fortified (5 microg vitamin D3) milk for 12 wks from January to April. Mean 25OHD was similar between groups at week 0 (control 74 vs 76 nmol/L) and fell significantly in both groups over the 12 weeks (control 53 nmol/L, fortified 65 nmol/L; p < 0.001). After 12 wks the fortified milk group had a serum 25OHD 19% (95% CI; 7, 32%) higher (10 nmol/L) than the control group after adjusting for baseline levels (p < 0.001). Daily consumption of fortified milk providing the current AI of 5 microg day vitamin D3 for 12 weeks resulted in higher 25OHD concentrations than control milk. This dose was not sufficient to prevent the seasonal decline in 25OHD. This study suggests an AI of 5 microg may be inadequate for New Zealanders to allow for seasonal changes in sunlight exposure, and is unlikely sufficient for other populations with low sunlight exposure.

Homocysteine-lowering vitamins do not lower plasma S-adenosylhomocysteine in older people with elevated homocysteine concentrations.

Elevated plasma total homocysteine (tHcy) is a risk factor for vascular disease but lowering tHcy with B-vitamins, including folate, has generally not reduced vascular events in secondary prevention trials. Elevated plasma S-adenosylhomocysteine (AdoHcy) concentration may be a more sensitive indicator of vascular disease than plasma tHcy. However, unlike tHcy, plasma AdoHcy did not correlate with folate concentration in one study indicating that folate supplementation may not lower AdoHcy. Our aim was to determine whether providing B-vitamin supplements to healthy older people with elevated tHcy (>13 micromol/l) affects plasma AdoHcy and S-adenosylmethionine (AdoMet) concentrations. Healthy older participants (n 276; > or = 65 years) were randomised to receive a daily supplement containing folate (1 mg), vitamin B12 (500 microg) and vitamin B6 (10 mg), or placebo, for 2 years. Of these participants, we selected the first fifty participants in each treatment group and measured plasma AdoHcy and AdoMet. Plasma tHcy was 4.4 (95 % CI 3.2, 5.6; P < 0.001) micromol/l lower at 2 years in the vitamins group compared with the placebo group. At 2 years, there were no significant differences in plasma AdoMet (+4 % (95 % CI - 2, 11); P = 0.19), AdoHcy ( - 1 % (95 % CI - 10, 8); P = 0.61) or the AdoMet:AdoHcy ratio (0.22 (95 % CI - 0.04, 0.49); P = 0.10) between the two groups. In conclusion, B-vitamin supplementation of older people lowered plasma tHcy but had no effect on plasma AdoMet or AdoHcy concentration. If elevated plasma AdoHcy is detrimental, this may explain why B-vitamins have generally failed to reduce vascular events in clinical trials.

Folate and vitamin B12 status of women of reproductive age living in Hanoi City and Hai Duong Province of Vietnam.

OBJECTIVES: To assess the folate and vitamin B12 status of a group of Vietnamese women of reproductive age and to estimate the rate of neural tube defects (NTD) based on red blood cell (RBC) folate concentrations. DESIGN AND SUBJECTS: A representative sample of non-pregnant women (15-49 years) living in Hanoi City (n 244) and Hai Duong Province (n 245). MEASURES: RBC folate, plasma vitamin B12 and plasma holo-transcobalamin (holoTC), a sensitive indicator of vitamin B12 status. RESULTS: Mean (95% CI) concentrations of RBC folate, plasma B12 and plasma holoTC were 856 (837, 876) nmol/l, 494 (475, 513) pmol/l and 78 (74, 82) pmol/l, respectively. Only 3% and 4% of women had plasma B12 and holoTC concentrations indicative of deficiency. No woman had an RBC folate concentration indicative of deficiency (<317 nmol/l). Only 47% of women had an RBC folate concentration > or = 905 nmol/l. Accordingly, we predict the NTD rate in these regions of Vietnam to be 14.7 (14.2, 15.1) per 10,000 pregnancies. CONCLUSION: There was no evidence of folate and vitamin B12 deficiency among this population of Vietnamese women. However, suboptimal folate status may be placing three out of five women at increased risk of NTD. Reductions in NTD rates are still possible and women would benefit from additional folic acid during the periconceptional period from either supplements or fortified foods.

Vitamin D insufficiency in New Zealanders during the winter is associated with higher parathyroid hormone concentrations: implications for bone health?

BACKGROUND: Parathyroid hormone concentration (PTH) is elevated in vitamin D insufficiency and when prolonged, this condition leads to reduced bone mass and possibly osteoporosis. The threshold of 25-hydroxyvitamin D above which PTH plateaus, is a criterion often used to define vitamin D adequacy. AIMS: To determine whether the higher rates of vitamin D inadequacy reported in the winter than summer months in New Zealand also result in higher PTH concentrations. Also to explore the relationship between 25-hydroxyvitamin D and PTH concentrations in a New Zealand population to determine if a threshold exists for plasma 25-hydroxyvitamin D concentration. METHODS: Plasma 25-hydroxyvitamin D and PTH concentrations were determined in 342 volunteers living in Invercargill and Dunedin (latitude 45-46 degrees S) in late summer (February) and early spring (October). RESULTS: Mean plasma 25-hydroxyvitamin D concentration was higher in the late summer versus early spring (79 vs 51 nmol/L; p<0.001). The lower plasma 25-hydroxyvitamin D in early spring versus summer was associated with a 0.2 pmol/L (p<0.001) higher PTH concentration. A threshold of 61 nmol/L was estimated for plasma 25-hydroxyvitamin D, above which there was no further decrease in PTH concentration. DISCUSSION: The higher PTH concentration in winter than summer suggests that the low 25-hydroxyvitamin D concentration in the winter months may be having an adverse effect on bone health. Many New Zealanders have 25-hydroxyvitamin D concentrations less than 62 nmol/L, especially in winter. Strategies to improve the vitamin D status of the population such as supplementation and food fortification may be needed.

Multiple micronutrient deficiencies persist during early childhood in Mongolia.

Data on the prevalence of micronutrient deficiencies in children in Mongolia is limited. We therefore determined the prevalence of anaemia, iron deficiency anaemia (IDA), and deficiencies of iron, folate, vitamin A, zinc, selenium, and vitamin D among young Mongolian children. Anthropometry and non-fasting morning blood samples were collected from 243 children aged 6-36 months from 4 districts in Ulaanbaatar and 4 rural capitols for haemoglobin (Hb), serum ferritin, folate, retinol, zinc, selenium, and 25-hydroxyvitamin D (25-OHD) assays. Children with alpha-1-glycoprotein >1.2mg/L (n=27) indicative of chronic infection were excluded, except for folate, selenium, and 25-hydroxyvitamin D assays. Of the children 14.5% were stunted and none were wasted. Zn deficiency (serum Zn <9.9 micromol/L) had the highest prevalence (74%), followed by vitamin D deficiency 61% (serum 25-OHD<25 nmol/L). The prevalence of anaemia (24%) and iron deficiency anaemia (IDA) (16%) was lower, with the oldest children (24-36 mos) at lowest risk. Twenty one percent of the children had low iron stores, and 33% had vitamin A deficiencies (serum retinol < 0.70 micromol/L), even though two thirds had received vitamin A supplements. Serum selenium values were low, perhaps associated with low soil selenium concentrations. In contrast, no children in Ulaanbaatar and only 4% in the provincial capitols had low serum folate values (<6.8 nmol/L). Regional differences (p<0.05) existed for anaemia, deficiencies of vitamin A, folate, and selenium, but not for zinc or IDA. Of the children, 78% were at risk of > or = two coexisting micronutrient deficiencies emphasizing the need for multimicronutrient interventions in Mongolia.

Lowering plasma homocysteine concentrations of older men and women with folate, vitamin B-12, and vitamin B-6 does not affect the proportion of (n-3) long chain polyunsaturated fatty acids in plasma phosphatidylcholine.

There is evidence to suggest that folate, homocysteine, or both affect the (n-3) long chain PUFA composition of tissues; however, this evidence is derived largely from experiments with animals and small observational studies in humans. Results from randomized controlled trials are needed. The objective of this study was to determine whether homocysteine lowering with a B vitamin supplement affects the proportion of (n-3) long-chain PUFA in plasma phosphatidylcholine. We conducted a double-blind, placebo-controlled, randomized clinical trial involving 253 participants, 65 y or older, with plasma homocysteine concentrations of at least 13 micromol/L. Participants in the vitamin group (n = 127) took a daily supplement containing 1000 microg folate, 500 microg vitamin B-12, and 10 mg vitamin B-6 for 2 y. The fatty acid composition of plasma phosphatidylcholine was measured at baseline and at 2 y. Plasma homocysteine concentrations during the course of the study were 4.4 micromol/L lower in the vitamin group than in the placebo group. The proportions of eicosapentaenoic, docosapentaenoic, and docosahexaenoic acids in plasma phosphatidylcholine did not differ between the vitamin and placebo groups at 2 y; the mean differences after adjusting for baseline values and sex were -0.03 (99% CI: -0.22, 0.16), 0.03 (99% CI: -0.03, 0.09), and -0.02 (99% CI: -0.27, 0.24) mol%, respectively. Lowering plasma homocysteine concentrations of older men and women with folate, vitamin B-12, and vitamin B-6 had no effect on the proportion of (n-3) long-chain PUFA in plasma phosphatidylcholine.

Very high rates of vitamin D insufficiency in women of child-bearing age living in Beijing and Hong Kong.

We aimed to describe the vitamin D status of young women living in two Chinese cities in the spring--Beijing in the north (latitude 39 degrees north) and Hong Kong (latitude 22 degrees north) in the south. We also examined the relationship between serum 25-hydroxyvitamin D and parathyroid hormone (PTH) concentrations to determine a threshold for serum 25-hydroxyvitamin D above which there is no further suppression of PTH. Finally, we examined whether dietary Ca intake influences this relationship. Non-pregnant women aged 18-40 years (n 441) were recruited between February and June. Fasting blood was collected and dietary intakes were assessed using 5 d food records. Mean serum 25-hydroxyvitamin D concentration was lower in Beijing than Hong Kong women (29 v. 34 nmol/l; P < 0.001). Vitamin D deficiency (< or = 25 nmol/l) was indicated in 40% of Beijing and 18% of Hong Kong women, and over 90% of women in both cities were insufficient (< or = 50 nmol/l). Mean Ca and vitamin D intakes were 478 mg/d and 2.0 microg/d, respectively. The relationship between 25-hydroxyvitamin D concentration and PTH was linear throughout the range with a slope of -0.36 (different from 0; P < 0.001; R 0.26), with no apparent threshold. There was no influence of Ca intake on the relationship between 25-hydroxyvitamin D and PTH concentration. Vitamin D deficiency is common and insufficiency is very common in non-pregnant women in Hong Kong and Beijing during spring. Serum 25-hydroxyvitamin D was inversely associated with PTH with no apparent threshold. Strategies such as vitamin D fortification or supplementation may be required.

Red cell folate and predicted neural tube defect rate in three Asian cities.

BACKGROUND: Periconceptional folic acid reduces neural tube defect (NTD) risk. Red blood cell folate concentration is inversely associated with NTD risk. In many countries there is a lack of information on NTD rates. Red cell folate status in women of childbearing age may be a surrogate for NTD rates and may be helpful in identifying countries or regions most likely to benefit from improved folate status. OBJECTIVE: To predict NTD rates using red cell folate concentrations in women of childbearing age living in three Asian cities Design: Cross-sectional convenience samples of non-pregnant women living in Beijing (n=220), Kuala Lumpur (n=389), and Jakarta (n=129). RESULTS: Red cell folate concentrations were highest (p<0.001) in women from Jakarta at 872 nmol/L (95% CI; 833, 910) followed by Kuala Lumpur at 674 nmol/L (95% CI: 644, 704) and lowest in Beijing at 563 nmol/L (95% CI: 524, 601). Accordingly, predicted NTD rates were highest in Beijing at 30/10000 (95% CI: 27, 33), followed by Kuala Lumpur at 24/10000 (95% CI: 22, 25), and lowest in Jakarta at 15/10000 (95% CI: 14,15). CONCLUSION: Our red blood cell folate data suggests that of the three cities improving the folate status of women in Beijing would have the greatest impact on NTD rates.

Reliable Change Index scores for persons over the age of 65 tested on alternate forms of the Rey AVLT.

An issue that often confronts the clinician referred an elderly person for neuropsychological assessment is how to interpret the significance of changes in test scores over time. In this report, data useful for estimating the statistical significance of changes on the Rey Auditory Verbal Learning Test (AVLT) are presented. The sample tested comprised 253 healthy persons aged 65 and over taking part in a randomized double-blind trial of the effect on cognitive performance of lowering homocysteine using dietary supplements. Results were based on the full sample because of the absence of any treatment effects. Test-retest data with a 1-year interval were used to estimate reliability coefficients and to calculate reliable change indices. The magnitude of a change necessary for a deterioration or improvement in scores at the two-tailed 90% confidence interval is given for the full sample, and persons above and below the age of 75.

Lowering homocysteine with B vitamins has no effect on blood pressure in older adults.

An elevated circulating homocysteine concentration is associated with the risk of cardiovascular disease. The mechanism by which an elevated homocysteine increases cardiovascular risk is unclear but may be mediated in part by elevating blood pressure. It is well established that supplements containing folate, vitamins B-12, and B-6 lower homocysteine concentrations. However, the effect of homocysteine-lowering vitamins on blood pressure has not been well studied. We sought to determine whether lowering homocysteine with B vitamins lowers blood pressure in healthy older people with elevated homocysteine concentrations. Two hundred seventy-six healthy older participants (> or = 65 y) with a homocysteine > or = 13 micromol/L were randomized to receive a daily supplement containing folate (1 mg), vitamin B-12 (500 microg), and vitamin B-6 (10 mg), or a placebo, for 2 y. Plasma homocysteine was lower in the Vitamins group than the Placebo group at both 1 [-4.3 micromol/L (95% CI; -4.9, -3.7)] and 2 y [-4.4 micromol/L (95% CI: -5.3, -3.6)]. Systolic and diastolic blood pressures as well as pulse pressure in the Vitamins group did not differ from the Placebo group over the duration of the trial. The mean differences in blood pressures, adjusted for baseline values, did not exceed 1 mm Hg. Supplemental B-vitamins lowered plasma homocysteine but had no effect on blood pressure in older people with elevated baseline homocysteine concentrations.

Lowering homocysteine with B vitamins has no effect on biomarkers of bone turnover in older persons: a 2-y randomized controlled trial.

BACKGROUND: In recent prospective studies, higher homocysteine concentrations were shown to be a risk factor for osteoporotic fractures in older persons. Supplements containing folate and vitamins B-12 and B-6 lower homocysteine concentrations. OBJECTIVE: The objective of the study was to determine in healthy older persons whether lowering homocysteine with B vitamins affects plasma biomarkers of bone turnover. DESIGN: Healthy older persons (n = 276; aged >or=65 y) were randomly assigned to receive either a daily supplement containing folate (1 mg), vitamin B-12 (500 microg), and vitamin B-6 (10 mg) or a placebo for 2 y. Of these participants, we selected 135 with baseline homocysteine concentrations >15.0 micromol/L, and we measured serum bone-specific alkaline phosphatase, a marker of bone formation, and bone-derived collagen fragments, a marker of bone resorption, at baseline and 2 y later. RESULTS: At 2 y, plasma homocysteine concentrations were 5.2 mumol/L (95% CI: 3.9, 6.6 micromol/L; P < 0.001) lower in the vitamin than in the placebo group. No significant differences were found in either serum bone-specific alkaline phosphatase (-0.3 microg/L; 95% CI: -2.8, 2.1 microg/L; P = 0.79) or bone-derived collagen fragments (-0.0 microg/L; 95% CI: -0.1, 0.1 microg/L; P = 0.76) between the vitamin and placebo groups, respectively, with 2 y of supplementation. CONCLUSION: Supplementation with folate and vitamins B-6 and B-12 lowered plasma homocysteine but had no beneficial effect on bone turnover at the end of 2 y, as assessed by biomarkers of bone formation and resorption.