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.

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.

The quality of diabetes care: a comparison between patients enrolled and not enrolled on a regional diabetes register.

AIMS: To determine whether diabetic patients enrolled on a regional diabetes register that provides annual general practitioner audit and recall reports receive better care than diabetic patients not enrolled. METHODS: Regional diabetes register enrolment status, demographic, clinical and laboratory data for the 2005 year were collected for identified diabetic patients attending 108 of 123 participating general practitioners. Means and standard deviations, or frequencies and percentages were calculated for the two study populations. Characteristics were compared with t-tests or the Chi square test. RESULTS: 3646 of 4749 identified diabetic patients were enrolled on the register and 1103 were not. The non-register population was younger by 1.8 years and for more than half of this population smoking status was unknown. Statistically significantly higher proportions of the register population had most recommended process measures (height, weight, feet, retina, urine ACR) completed within the audit interval. Higher proportions of the register population were prescribed ACE inhibitors (55 vs 47%), other antihypertensives (32 vs 27%) or lipid modifying medication (61 vs 54%). Co-morbidities were common in both groups. CONCLUSIONS: Well-organised centralised diabetes registers provide additional benefits for people with diabetes care. Up to date primary care registers with good call-recall systems are necessary for the delivery of effective structured diabetes care.

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.

Nutritional intervention in patients with type 2 diabetes who are hyperglycaemic despite optimised drug treatment--Lifestyle Over and Above Drugs in Diabetes (LOADD) study: randomised controlled trial.

OBJECTIVE: To determine the extent to which intensive dietary intervention can influence glycaemic control and risk factors for cardiovascular disease in patients with type 2 diabetes who are hyperglycaemic despite optimised drug treatment. DESIGN: Randomised controlled trial. SETTING: Dunedin, New Zealand. PARTICIPANTS: 93 participants aged less than 70 years with type 2 diabetes and a glycated haemoglobin (HbA(1c)) of more than 7% despite optimised drug treatments plus at least two of overweight or obesity, hypertension, and dyslipidaemia. INTERVENTION: Intensive individualised dietary advice (according to the nutritional recommendations of the European Association for the Study of Diabetes) for six months; both the intervention and control participants continued with their usual medical surveillance. MAIN OUTCOME MEASURES: HbA(1c) was the primary outcome. Secondary outcomes included measures of adiposity, blood pressure, and lipid profile. RESULTS: After adjustment for age, sex, and baseline measurements, the difference in HbA(1c) between the intervention and control groups at six months (-0.4%, 95% confidence interval -0.7% to -0.1%) was highly statistically significant (P=0.007), as were the decreases in weight (-1.3 kg, -2.4 to -0.1 kg; P=0.032), body mass index (-0.5, -0.9 to -0.1; P=0.026), and waist circumference (-1.6 cm, -2.7 to -0.5 cm; P=0.005). A decrease in saturated fat (-1.9% total energy, -3.3% to -0.6%; P=0.006) and an increase in protein (1.6% total energy, 0.04% to 3.1%; P=0.045) in the intervention group were the most striking differences in nutritional intake between the two groups. CONCLUSIONS: Intensive dietary advice has the potential to appreciably improve glycaemic control and anthropometric measures in patients with type 2 diabetes and unsatisfactory HbA(1c) despite optimised hypoglycaemic drug treatment. TRIAL REGISTRATION: Clinical trials NCT00124553.

Another approach to estimating the reliability of glycaemic index.

The usefulness of the glycaemic index (GI) of a food for practical advice for individuals with diabetes or the general population depends on its reliability, as estimated by intra-class coefficient (ICC), a measure having values between 0 and 1, with values closer to 1 indicating better reliability. We aimed to estimate the ICC of the postprandial blood glucose response to glucose and white bread, instant mashed potato and chickpeas using the incremental area under the curve (iAUC) and the GI of these foods. The iAUC values were determined in twenty healthy individuals on three and four occasions for white bread and glucose, respectively, and for potato and chickpeas on a single occasion. The ICC of the iAUC for white bread and glucose were 0.50 (95 % CI 0.27, 0.73) and 0.49 (95 % CI 0.22, 0.75), respectively. The mean GI of white bread was 81 (95 % CI 74, 90) with a reliability of 0.27 indicating substantial within-person variability. The GI of mashed potato and chickpeas were 87 (95 % CI 76, 101) and 28 (95 % CI 22, 37) respectively with ICC of 0.02 and 0.40.The ICC of the iAUC were moderate and those of the GI fair or poor, indicating the heterogeneous nature of individuals' responses. The unpredictability of individual responses even if they are the result of day-to-day variation places limitations on the clinical usefulness of GI. If the very different GI of potato and chickpeas are estimates of an individual's every-day response to different foods, then the GI of foods may provide an indication of the GI of a long-term diet.

Carnitine does not improve weight loss outcomes in valproate-treated bipolar patients consuming an energy-restricted, low-fat diet.

OBJECTIVES: Carnitine deficiency impairs fatty acid beta-oxidation and may partly explain weight gain in valproate-treated patients. The aim of this study was to determine whether l-carnitine supplementation improves weight loss outcomes in bipolar patients taking sodium valproate. METHODS: Sixty bipolar patients with clinically significant weight gain thought to be related to sodium valproate, who had been taking sodium valproate for >or=6 months, were randomized to l-carnitine (15 mg/kg/day) or placebo for 26 weeks, in conjunction with a moderately energy-restricted, low-fat diet. The primary outcome measure was weight change. RESULTS: l-carnitine had no effect on mean weight loss compared with placebo (-1.9 kg versus - 0.9 kg) (F = 0.778, df = 1,58, p = 0.381). The number of people in each group able to lose any weight was identical ( = 0, p = 1.0); more patients in the carnitine group (nine versus five) achieved a clinically significant weight loss (>or=5%) but this was not statistically significant (p = 1.0, Fisher's exact test). CONCLUSIONS: At the dose prescribed in this study carnitine supplementation did not improve weight loss outcomes in valproate-treated bipolar patients consuming an energy-restricted, low-fat diet.

A controlled trial of homocysteine lowering and cognitive performance.

BACKGROUND: The results of observational studies suggest that plasma homocysteine concentrations are inversely related to cognitive function in older people. Our objective was to test the hypothesis that lowering the plasma homocysteine concentration improves cognitive function in healthy older people. METHODS: We conducted a two-year, double-blind, placebo-controlled, randomized clinical trial involving 276 healthy participants, 65 years of age or older, with plasma homocysteine concentrations of at least 13 micromol per liter. Homocysteine-lowering treatment was a daily supplement containing folate (1000 microg) and vitamins B12 (500 microg) and B6 (10 mg). Tests of cognition were conducted at baseline and after one and two years of treatment. Treatment effects were adjusted for baseline values, sex, and education. RESULTS: On average, during the course of the study, the plasma homocysteine concentration was 4.36 micromol per liter (95 percent confidence interval, 3.81 to 4.91 micromol per liter) lower in the vitamin group than in the placebo group (P<0.001). Overall, there were no significant differences between the vitamin and placebo groups in the scores on tests of cognition. CONCLUSIONS: The results of this trial do not support the hypothesis that homocysteine lowering with B vitamins improves cognitive performance. (Australian Clinical Trials registry number, ACTR NO 12605000030673.).

Comparison of the effect of low-dose supplementation with L-5-methyltetrahydrofolate or folic acid on plasma homocysteine: a randomized placebo-controlled study.

BACKGROUND: Food fortification with folic acid has been introduced in several countries for the prevention of neural tube defects. Fortification has lowered total homocysteine (tHcy) concentrations in the US population, a consequence that may have health benefits. However, folic acid fortification could mask vitamin B-12 deficiency. Synthetic L-5-methyltetrahydrofolate (L-MTHF) may be more appropriate than folic acid as a fortificant because it is unlikely to mask the hematologic indicators of vitamin B-12 deficiency. OBJECTIVE: The objective of the study was to compare the effectiveness of 100 micro g folic acid/d with that of equimolar L-MTHF in lowering tHcy in healthy volunteers. DESIGN: The study was designed as a 24-wk, randomized, placebo-controlled intervention. Free-living healthy volunteers (n = 167) were randomly assigned to receive a daily supplement containing folic acid (100 microg), L-MTHF (113 microg), or placebo. Blood collected at baseline and at 8, 16, and 24 wk was analyzed for tHcy, plasma folate, and red blood cell folate (RCF) concentrations. RESULTS: At 24 wk, after adjustment for baseline values, mean (95% CI) tHcy was 14.6% (9.3, 19.5%) and 9.3% (3.7, 14.6%) lower, mean plasma folate was 34% (14, 56%) and 52% (30, 78%) higher, and mean RCF was 23% (12, 35%) and 31% (19, 44%) higher in the L-MTHF and folic acid groups, respectively, than in the placebo group. L-MTHF was more effective than was folic acid in lowering tHcy (P < 0.05). At 24 wk, the increases in plasma folate and RCF concentrations did not differ significantly between the 2 supplemented groups. CONCLUSION: Low-dose L-MTHF is at least as effective as is folic acid in reducing tHcy concentrations in healthy persons.

Dietary counseling to increase natural folate intake: a randomized, placebo-controlled trial in free-living subjects to assess effects on serum folate and plasma total homocysteine.

BACKGROUND: The association between vascular disease and elevated plasma total homocysteine (tHcy) concentrations is caused, in part, by inadequate intakes of dietary folate. Increasing folate intake either through supplements or foods naturally rich in folates has been shown to decrease tHcy concentrations. OBJECTIVE: The aim of this study was to determine whether a similar reduction in tHcy was possible in free-living persons receiving dietary counseling. DESIGN: The study included a 4-wk placebo-controlled dietary intervention trial in which participants consumed either unfortified breakfast cereal (control group) or an extra 350 micro g folate derived from food/d (dietary group). Serum folate and tHcy concentrations in both groups were measured before and after the intervention period, and the concentrations in the dietary group were also measured 17 wk after the intervention period. RESULTS: During the 4-wk intervention, mean dietary folate intake in the dietary group increased from 263 (95% CI: 225, 307) to 618 micro g/d (535, 714), resulting in a mean increase in serum folate of 37% (15%, 63%) and a decrease in tHcy from 12.0 (10.9, 13.3) to 11.3 micro mol/L (10.2, 12.5). A further decrease in tHcy occurred in the dietary group during follow-up, with a final tHcy concentration of 9.7 micro mol/L (8.8, 10.8). CONCLUSIONS: Increasing natural folate intake improved folate status and decreased tHcy concentrations to an extent that may significantly reduce the risk of vascular disease. Dietary modification may have advantages over folic acid fortification because the altered food-consumption patterns lead to increased intakes of several vitamins and minerals and decreased intakes of saturated fatty acids.