Estimation of the use of dietary supplements in the National Diet and Nutrition Survey: people aged 65 years and Over. An observed paradox and a recommendation

U-shaped Association Between Folic Acid Supplementation and the Risk of Gestational Diabetes Mellitus in Chinese Women

OBJECTIVE

Our aim in this study was to assess the association between folic acid (FA) supplementation before and during pregnancy and risk of gestational diabetes mellitus (GDM) in Chinese women.

METHODS

This case-control study was conducted at 2 hospitals in central China. A total of 1,300 pregnant women, including 396 GDM patients and 904 controls, participated in the study. Information on the dose and duration of FA supplementation was collected using a self-report questionnaire at enrolment (24 to 28 weeks of gestation).

RESULTS

We observed a U-shaped association between FA supplementation and GDM risk that demonstrated a 228% increased risk of GDM among women who never took FA supplements, a 28% increased risk among women who took supplements containing <400 μg/day FA or took FA supplements for <1 month and a 188% increased risk among women who took supplements containing ≥800 μg/day FA for an adequate duration (>1 month before pregnancy and >3 months during pregnancy) compared with women who took supplements containing 400 to 799 μg/day FA for an adequate duration (all p<0.05). For women who took supplements containing ≥800 μg/day FA for an adequate duration, the association between FA supplementation and GDM risk appeared to be stronger among those women with a prepregnancy body mass index (BMI) of ≥25 kg/m² than among those with a prepregnancy BMI of <25 kg/m² (p=0.006 for interaction).

CONCLUSIONS

There was a U-shaped association of FA supplementation with GDM risk; that is, FA supplementation both below and above the recommended levels may increase the risk of GDM.

Associations between self-reported symptoms of SARS-CoV-2 and dietary supplement use over the previous year during the first pandemic wave

During the initial wave of the COVID-19 pandemic, symptoms of infection varied widely among adults younger than 60 years. This cross-sectional investigation of adults ages 18-59 years explored associations between SARS-CoV-2 symptomatology and supplementation of micronutrients involved in immune function, such as multivitamins, vitamin D, vitamin C, vitamin E and zinc. Between August and December 2020, an online survey was completed by 287 respondents, averaging 33⋅3 ± 10⋅5 years, who recovered from SARS-CoV-2 infection within the previous 4 months. In regression models, intake of supplements over the previous year was not protective against number of symptoms or symptom severity. Despite higher rates of supplementation over the previous year, smokers experienced more symptoms and greater symptom severity than non-smokers. Micronutrient supplementation did not protect young adults from experiencing symptoms of SARS-CoV-2, but our results suggest that smoking cessation may be a more effective modifiable lifestyle factor.

The role of one-carbon metabolism and homocysteine in Parkinson’s disease onset, pathology and mechanisms

Parkinson’s disease (PD) is the second most common neurodegenerative disorder. It is characterised by the progressive degeneration of dopaminergic (DA) neurons. The cause of degeneration is not well understood; however, both genetics and environmental factors, such as nutrition, have been implicated in the disease process. Deficiencies in one-carbon metabolism in particular have been associated with increased risk for PD onset and progression, though the precise relationship is unclear. The aim of the present review is to determine the role of one-carbon metabolism and elevated levels of homocysteine in PD onset and pathology and to identify potential mechanisms involved. A search of PubMed, Google Scholar and Web of Science was undertaken to identify relevant human and animal studies. Case–control, prospective cohort studies, meta-analyses and non-randomised trials were included in the present review. The results from human studies indicate that polymorphisms in one-carbon metabolism may increase risk for PD development. There is an unclear role for dietary B-vitamin intake on PD onset and progression. However, dietary supplementation with B-vitamins may be beneficial for PD-affected individuals, particularly those onl-DOPA (levodopa orl-3,4-dihydroxyphenylalanine) treatment. Additionally, one-carbon metabolism generates methyl groups, and methylation capacity in PD-affected individuals is reduced. This reduced capacity has an impact on expression of disease-specific genes that may be involved in PD progression. During B-vitamin deficiency, animal studies report increased vulnerability of DA cells through increased oxidative stress and altered methylation. Nutrition, especially folates and related B-vitamins, may contribute to the onset and progression of PD by making the brain more vulnerable to damage; however, further investigation is required.

The balance between food and dietary supplements in the general population

In the past, vitamins and minerals were used to cure deficiency diseases. Supplements nowadays are used with the aim of reducing the risk of chronic diseases of which the origins are complex. Dietary supplement use has increased in the UK over recent decades, contributing to the nutrient intake in the population, but not necessarily the proportion of the population that is sub-optimally nourished; therefore, not reducing the proportion below the estimated average requirement and potentially increasing the number at risk of an intake above the safety limits. The supplement nutrient intake may be objectively monitored using circulation biomarkers. The influence of the researcher in how the supplements are grouped and how the nutrient intakes are quantified may however result in different conclusions regarding their nutrient contribution, the associations with biomarkers, in general, and dose-response associations specifically. The diet might be sufficient in micronutrients, but lacking in a balanced food intake. Since public-health nutrition guidelines are expressed in terms of foods, there is potentially a discrepancy between the nutrient-orientated supplement and the quality of the dietary pattern. To promote health, current public-health messages only advocate supplements in specific circumstances, but not in optimally nourished populations.

Selected B vitamins and their possible link to the aetiology of age-related sarcopenia: relevance of UK dietary recommendations

The possible roles of selected B vitamins in the development and progression of sarcopenia are reviewed. Age-related declines in muscle mass and function are associated with huge and increasing costs to healthcare providers. Falls and loss of mobility and independence due to declining muscle mass/function are associated with poor clinical outcomes and their prevention and management are attractive research targets. Nutritional status appears a key modifiable and affordable intervention. There is emerging evidence of sarcopenia being the result not only of diminished anabolic activity but also of declining neurological integrity in older age, which is emerging as an important aspect of the development of age-related decline in muscle mass/function. In this connection, several B vitamins can be viewed as not only cofactors in muscle synthetic processes, but also as neurotrophic agents with involvements in both bioenergetic and trophic pathways. The B vitamins thus selected are examined with respect to their relevance to multiple aspects of neuromuscular function and evidence is considered that requirements, intakes or absorption may be altered in the elderly. In addition, the evidence base for recommended intakes (UK recommended daily allowance) is examined with particular reference to original datasets and their relevance to older individuals. It is possible that inconsistencies in the literature with respect to the nutritional management of sarcopenia may, in part at least, be the result of compromised micronutrient status in some study participants. It is suggested that in order, for example, for intervention with amino acids to be successful, underlying micronutrient deficiencies must first be addressed/eliminated.

Nutrition in the Very Old

The population of older adults aged 85 years and over (the very old) is growing rapidly in many societies because of increases in life expectancy and reduced mortality at older ages. In 2016, 27.3 million very old adults were living in the European Union, and in the UK, 2.4% of the population (1.6 million) were aged 85 and over. Very old age is associated with increased risks of malnutrition, multimorbidity, and disability. Diet (nutrition) is a modifiable risk factor for multiple age-related conditions, including sarcopenia and functional decline. Dietary characteristics and nutrient intakes of the very old have been investigated in several European studies of ageing to better understand their nutritional requirements, which may differ from those in the young-old. However, there is a major gap in regard to evidence for the role of dietary patterns, protein, vitamin D and other nutrients for the maintenance of physical and cognitive functioning in later life. The Newcastle 85+ Study, UK and the Life and Living in Advanced Age, New Zealand are unique studies involving single birth cohorts which aim to assess health trajectories in very old adults and their biological, social and environmental influences, including nutrition. In this review, we have updated the latest findings in nutritional epidemiology with results from these studies, concentrating on the diet-physical functioning relationship.

Suboptimal maternal and cord plasma pyridoxal 5' phosphate concentrations are uncommon in a cohort of Canadian pregnant women and newborn infants

Vitamin B₆ is important in fetal development, but little is known of the vitamin B₆ status of pregnant women and newborns in North America and potential modifying factors. This prospective study determined maternal and cord plasma concentrations of pyridoxal 5' phosphate (PLP; an indicator of vitamin B₆ status) in a convenience sample of 368 Canadian pregnant women and their newborns. The association of maternal intake of vitamin B₆ and fetal genetic variants with cord plasma PLP and homocysteine concentrations was also examined. Dietary and supplemental intakes of vitamin B₆ were assessed in early and mid to late pregnancy. PLP concentrations were measured in maternal plasma in early pregnancy and at delivery, and in cord plasma. Six fetal variants of the MTHFR and CβS genes were assessed for their association with cord plasma PLP and homocysteine concentrations. Geometric mean (95% CI) PLP concentrations were 107 (98, 116) nmol/L in early pregnancy and 58 (53, 62) nmol/L at delivery, respectively, and 296 (275, 319) nmol/L in cord blood (p < .0001). During early pregnancy and at delivery, 3.6% and 5.5% of women had plasma PLP concentrations <20 nmol/L, respectively. Ninety eight percent of the women with supplemental B₆ intake of at least the recommended dietary allowance had PLP concentrations >20 nmol/L. Fetal genetic variants were not associated with cord PLP and homocysteine concentrations. Vitamin B₆ deficiency is uncommon in a cohort of Canadian pregnant women due largely to prevalent vitamin B₆ supplement use.

B-Vitamin Intake from Diet and Supplements and Breast Cancer Risk in Middle-Aged Women: Results from the Prospective NutriNet-Santé Cohort

Experimental studies suggest a protective effect of B-vitamins on breast cancer risk, potentially modulated by alcohol intake. However, epidemiological studies are limited, especially regarding non-folate B-vitamins. Furthermore, few studies included quantitative assessment of supplemental intake. This prospective study aimed to investigate the associations between intakes of B-vitamins (dietary, supplemental, total) and breast cancer risk. 27,853 women aged ≥45 years from the NutriNet-Santé cohort (2009–2016) were included, with a median follow-up time of 4.2 years. Dietary data were collected using repeated 24 h records. A specific questionnaire assessed dietary supplement use over a 12-month period. A composition database of 8000 supplements was developed. Associations were characterized by multivariable Cox models, and 462 incident breast cancers were diagnosed. Dietary (HR_Q4vs.Q1 = 0.74 (0.55, 0.99), P-trend = 0.05), supplemental (HR_Q4vs.Q1 = 0.61 (0.38, 0.98), P-trend = 0.05), and total (HR_Q4vs.Q1 = 0.67 (0.50, 0.91), P-trend = 0.01) pyridoxine intakes were inversely associated with breast cancer risk. Total thiamin intake was borderline inversely associated with breast cancer risk (HR_{per 1-unit increment} = 0.78 (0.61, 1.00), P = 0.05). Statistically significant interactions between alcohol consumption and B-vitamin (thiamin, riboflavin, niacin, pantothenic acid, pyridoxine, folate, and cobalamin) supplemental intake were observed, the latter being inversely associated with breast cancer risk in non-to-low alcohol drinkers but not in higher drinkers. This large prospective study, including quantitative assessment of supplemental intake, suggests a potential protective effect of pyridoxine and thiamin on breast cancer risk in middle-aged women.

Folate and Vitamin B12-Related Biomarkers in Relation to Brain Volumes

AIM

We investigated cross-sectional associations between circulating homocysteine, folate, biomarkers of vitamin B₁₂ status and brain volumes. We furthermore compared brain volumes of participants who received daily folic acid and vitamin B₁₂ supplementation with participants who did not.

METHODS

Participants of the B-PROOF study (n = 2919) were assigned to 400 µg folic acid and 500 µg vitamin B₁₂, or a placebo. After two years of intervention, T₁-weighted magnetic resonance imaging (MRI) scans were made in a random subsample (n = 218) to obtain grey and white matter volume, and total brain volume (TBV). Plasma homocysteine, serum folate, vitamin B₁₂, holotranscobalamin, and methylmalonic acid concentrations were measured.

RESULTS

Multiple linear regression analyses showed inverse associations between plasma homocysteine with TBV (β = -0.91, 95% CI -1.85-0.03; p = 0.06) and between serum folate and TBV (β = -0.20, 95% CI -0.38, -0.02; p = 0.03). No significant associations were observed for serum vitamin B₁₂ and holotranscobalamin. Fully adjusted ANCOVA models showed that the group that received B-vitamins had a lower TBV (adjusted mean 1064, 95% CI 1058-1069 mL) than the non-supplemented group (1072, 95% CI 1067-1078 mL, p = 0.03).

CONCLUSIONS

Results were contradictory, with higher Hcy levels associated with lower TBV, but also with higher folate levels associated with lower TBV. In addition, the lack of a baseline measurement withholds us from giving recommendations on whether folic acid and vitamin B₁₂ supplementation will be beneficial above and beyond normal dietary intake for brain health.

Dietary B Vitamins and a 10-Year Risk of Dementia in Older Persons

B vitamins may lower the risk of dementia, yet epidemiological findings, mostly from countries with folic acid fortification, have remained inconsistent. We evaluated in a large French cohort of older persons the associations between dietary B vitamins and long-term incident dementia. We included 1321 participants from the Three-City Study who completed a 24 h dietary recall, were free of dementia at the time of diet assessment, and were followed for an average of 7.4 years. In Cox proportional hazards models adjusted for multiple potential confounders, including overall diet quality, higher intake of folate was inversely associated with the risk of dementia (p for trend = 0.02), with an approximately 50% lower risk for individuals in the highest compared to the lowest quintile of folate (HR = 0.47; 95% CI 0.28; 0.81). No association was found for vitamins B6 and B12. In conclusion, in a large French cohort with a relatively low baseline folate status (average intake = 278 µg/day), higher folate intakes were associated with a decreased risk of dementia.

Dietary intake and biomarker status of folate in Swedish adults

PURPOSE

National data on folate status are missing in Sweden, and regional data indicate folate insufficiency in up to more than 25% of the study populations. The objectives were to determine folate intake and status in the adult Swedish population as well as identifying dietary patterns associated with beneficial folate status.

METHODS

Folate intake was estimated using a web-based 4-d food record in adults aged 18-80 years (n = 1797). Folate status was measured as erythrocyte (n = 282) and plasma folate concentrations (n = 294). Factor analysis was used to derive a dietary pattern associated with a higher folate status.

RESULTS

Median folate intake was 246 µg/day (Q ₁ = 196, Q ₃ = 304, n = 1797) and for women of reproductive age 227 µg/day (Q ₁ = 181, Q ₃ = 282, n = 450). As dietary folate equivalents (DFE), median intake was 257 µg/day (Q ₁ = 201, Q ₃ = 323) and for women of reproductive age 239 µg/day (Q ₁ = 185, Q ₃ = 300). Low blood folate concentrations were found in 2% (erythrocyte concentrations <317 nmol/L) and 4% (plasma concentrations <6.8 nmol/L) of the participants, respectively. None of the women of reproductive age had erythrocyte folate concentrations associated with the lowest risk of neural tube defects. Dietary patterns associated with higher folate status were rich in vegetables, pulses and roots as well as cheese and alcoholic beverages, and low in meat.

CONCLUSIONS

Prevalence of low erythrocyte folate concentrations was low in this population, and estimated dietary intakes are well above average requirement. However, to obtain a folate status optimal for prevention of neural tube defects major dietary changes are required and folic acid supplements recommended prior to conception.

Intakes of Folate and Vitamin B12 and Biomarkers of Status in the Very Old: The Newcastle 85+ Study

Very old adults are at increased risk of folate and vitamin B12 deficiencies due to reduced food intake and gastrointestinal absorption. The main aim was to determine the association between folate and vitamin B12 intake from total diets and food groups, and status. Folate or vitamin B12 intakes (2 × 24 h multiple pass recalls) and red blood cell (RBC) folate or plasma vitamin B12 (chemiluminescence immunoassays) concentrations were available at baseline for 731 participants aged 85 from the Newcastle 85+ Study (North-East England). Generalized additive and binary logistic models estimated the associations between folate and vitamin B12 intakes from total diets and food groups, and RBC folate and plasma B12. Folate intake from total diets and cereal and cereal products was strongly associated with RBC folate (p < 0.001). Total vitamin B12 intake was weakly associated with plasma vitamin B12 (p = 0.054) but those with higher intakes from total diets or meat and meat products were less likely to have deficient status. Women homozygous for the FUT2 G allele had higher concentrations of plasma vitamin B12. Cereals and cereal products are a very important source of folate in the very old. Higher intakes of folate and vitamin B12 lower the risk of "inadequate" status.

Barriers to and Facilitators of the Consumption of Animal-Based Protein-Rich Foods in Older Adults

Protein intakes in the older population can be lower than recommended for good health, and while reasons for low protein intakes can be provided, little work has attempted to investigate these reasons in relation to actual intakes, and so identify those of likely greatest impact when designing interventions. Questionnaires assessing: usual consumption of meat, fish, eggs and dairy products; agreement/disagreement with reasons for the consumption/non-consumption of these foods; and several demographic and lifestyle characteristics; were sent to 1000 UK community-dwelling adults aged 65 years and over. In total, 351 returned questionnaires, representative of the UK older population for gender and age, were suitable for analysis. Different factors were important for consumption of the four food groups, but similarities were also found. These similarities likely reflect issues of particular concern to both the consumption of animal-based protein-rich foods and the consumption of these foods by older adults. Taken together, these findings suggest intakes to be explained by, and thus that strategies for increasing consumption should focus on: increasing liking/tastiness; improving convenience and the effort required for food preparation and consumption; minimizing spoilage and wastage; and improving perceptions of affordability or value for money; freshness; and the healthiness of protein-rich foods.

Cod liver oil supplement consumption and health: cross-sectional results from the EPIC-Norfolk cohort study

Supplement users (SU) make healthy lifestyle choices; on the other hand, SU report more medical conditions. We hypothesised that cod liver oil (CLO) consumers are similar to non-supplement users, since CLO use might originate from historical motives, i.e., rickets prevention, and not health consciousness. CLO consumers were studied in order to identify possible confounders, such as confounding by indication. The European Prospective Investigation into Cancer (EPIC) investigates causes of chronic disease. The participants were 25,639 men and women, aged 40–79 years, recruited from general practices in Norfolk, East-Anglia (UK). Participants completed questionnaires and a health examination between 1993 and 1998. Supplement use was measured using 7-day diet diaries. CLO was the most common supplement used, more prevalent among women and associated with not smoking, higher physical activity level and more favourable eating habits. SU had a higher occurrence of benign growths and bone-related diseases, but CLO was negatively associated with cardiovascular-related conditions. Although the results of SU characteristics in EPIC-Norfolk are comparable with studies worldwide, the CLO group is different from SU in general. Confounding by indication takes place and will need to be taken into account when analysing prospective associations of CLO use with fracture risk and cardiovascular diseases.

Calcium and vitamin D supplementation: state of the art for daily practice

BACKGROUND

Calcium and vitamin D play an essential role in bone metabolism but deficiency and/or inadequate intake are common.

OBJECTIVES

To describe a practical approach based on the literature regarding clinically important aspects of calcium and vitamin D supplementation.

METHODS

A systematic evaluation of relevant literature in Medline was conducted. We included physiological studies, publications on relevant guidelines, meta-analysis, randomized clinical trials, and cohort studies.

RESULTS

An adequate calcium intake and vitamin D supplementation is recommended in most guidelines xon fracture prevention. Daily supplementation with 800 IU is advocated in most guidelines, appears to be safe, and with this approach it is generally not necessary to determine vitamin D levels. There are no data on additional effects of loading doses of vitamin D on fracture or fall prevention. Calcium supplementation should be tailored to the patient's need: usually 500 mg per day is required. The intestinal absorption of calcium citrate is approximately 24% better than that of calcium carbonate independent of intake with meals. Data on difference between calcium absorption with calcium carbonate compared to calcium citrate with simultaneous use of proton pump inhibitors are lacking. Concern has arisen about a possible link between calcium supplementation and an increased risk of myocardial infarction. Probably only well-designed prospective randomized controlled trials will be able to allow definite conclusions on this subject.

CONCLUSION

Daily supplementation with 800 IU vitamin D is a practical and safe strategy without the need for prior determination of vitamin D levels. Calcium supplementation should be tailored to the patient's need based on total daily dietary calcium intake. In most patients 500 mg per day is required to achieve a total intake of 1,200 mg, or in some 1,000 mg per day. More calcium is absorbed from calcium citrate compared to calcium carbonate.

Differences in dietary supplement use and secular and seasonal trends assessed using three different instruments in the EPIC-Norfolk population study

OBJECTIVE

Supplement use has increased over time and measurements of supplement use are dependent on instruments chosen. Therefore, we investigated three different questionnaires to measure supplement use and whether these results were associated with age, year of recruitment (secular trend, 1993-1998), and seasonal trends.

DESIGN

The questionnaires were self-administered within a median time interval of 54 days and included a Health and Lifestyle Questionnaire (1-year recall), a Food Frequency Questionnaire (1-year recall), and a 7-day diet diary.

SETTING

Men and women, aged 40-79 years from the general population living in Norfolk (East Anglia, UK), recruited between 1993 and 1998 in the European Prospective Investigation into Cancer Study (EPIC-Norfolk).

RESULTS

The prevalence of supplement use estimated with different instruments ranged from 31.7% to 39.0% for men and 45.0% to 54.3% for women. Agreement was substantial with kappa-statistics between 0.72 and 0.81. Participants' age (men only) and recruitment year were independently associated with supplement use; season showed inconsistent results.

CONCLUSIONS

The diary provides a good agreement as measured by the kappa-statistic, compared to more long-term measures of supplement use classification. The secular and seasonal trends in supplement use and type of assessment instrument need to be taken into account in studies on health and supplement use.

Intakes of dietary folate and other B vitamins are associated with risks of esophageal adenocarcinoma, Barrett's esophagus, and reflux esophagitis

Folate is implicated in carcinogenesis via effects on DNA synthesis, repair, and methylation. Efficient folate metabolism requires other B vitamins and is adversely affected by smoking and alcohol. Esophageal adenocarcinoma (EAC) may develop through a process involving inflammation [reflux esophagitis (RE)] leading to metaplasia [Barrett's esophagus (BE)] and carcinoma. Within a population-based, case-control study, we investigated associations between dietary folate and related factors and risks of EAC, BE, and RE. EAC and BE cases had histologically confirmed disease; RE cases had endoscopically visible inflammation. Controls, age-sex frequency matched to EAC cases, were selected through population and general practice registers. Participants underwent structured interviews and completed food-frequency questionnaires. Multivariate ORs and 95% CIs were computed using logistic regression. A total of 256 controls and 223 EAC, 220 BE, and 219 RE cases participated. EAC risk decreased with increasing folate intake (OR highest vs. lowest = 0.56; 95% CI: 0.31, 1.00; P-trend < 0.01). Similar trends were found for BE (P-trend < 0.01) and RE (P-trend = 0.01). Vitamin B-6 intake was significantly inversely related to risks of all 3 lesions. Riboflavin intake was inversely associated with RE. Vitamin B-12 intake was positively associated with EAC. For EAC, there was a borderline significant interaction between folate intake and smoking (P-interaction = 0.053); compared with nonsmokers with high (≥ median) folate intake, current smokers with low intakes (<median) had an 8-fold increased risk (OR: 8.15; 95% CI: 3.61, 18.40). The same group had increased BE risk (OR: 2.93; 95% CI: 1.24, 6.92; P-interaction = 0.12). Folate and other dietary methyl-group factors are implicated in the etiology of EAC and its precursors.

Randomized, placebo-controlled, calcium supplementation trial in pregnant Gambian women accustomed to a low calcium intake: effects on maternal blood pressure and infant growth

BACKGROUND

Dietary calcium intake in rural Gambian women is very low (∼350 mg/d) compared with international recommendations. Studies have suggested that calcium supplementation of women receiving low-calcium diets significantly reduces risk of pregnancy hypertension.

OBJECTIVE

We tested the effects on blood pressure (BP) of calcium carbonate supplementation (1500 mg Ca/d) in pregnant, rural Gambian women.

DESIGN

The study was a randomized, double-blind, parallel, placebo-controlled supplementation trial from 20 wk of gestation (P20) until delivery (calcium: n = 330; placebo; n = 332). BP and anthropometric measures were taken at P20 and then 4 weekly until 36 wk of gestation (P36), and infant anthropometric measures were taken at 2, 13, and 52 wk postdelivery.

RESULTS

A total of 525 (calcium: n = 260; placebo: n = 265) women had BP measured at P36 and subsequently delivered a healthy term singleton infant. Mean compliance was 97%, and urinary calcium measures confirmed the group allocation. At P20, the mean (±SD) systolic blood pressure (SBP) was 101.2 ± 9.0 and 102.1 ± 9.3 mm Hg, and diastolic blood pressure (DBP) was 54.5 ± 7.3 and 55.8 ± 7.8 mm Hg, in the calcium and placebo groups, respectively. The intention-to-treat analysis that was adjusted for confounders showed no significant effect of calcium supplementation on the change between P20 and P36 (calcium compared with placebo; mean ± SEM) in SBP (-0.64 ± 0.65%; P = 0.3) or DBP (-0.22 ± 1.15%; P = 0.8). There was no significant effect of supplementation on BP, pregnancy weight gain, weight postpartum, or infant weight, length, and other measures of growth. However, the comparability of the original randomly assigned groups may have been compromised by the exclusion of 20.7% of women from the final analysis.

CONCLUSIONS

Calcium supplementation did not affect BP in pregnancy. This result may have been because the Gambian women were adapted to a low dietary calcium intake, and/or obesity, high gestational weight gain, high underlying BP, tobacco use, alcohol consumption, and sedentary lifestyles were rare. This trial was registered at the International Standard Randomized Controlled Trial Register (www.controlled-trials.com/mrct/) as ISRCTN96502494.

Mapping low intake of micronutrients across Europe

Achieving an understanding of the extent of micronutrient adequacy across Europe is a major challenge. The main objective of the present study was to collect and evaluate the prevalence of low micronutrient intakes of different European countries by comparing recent nationally representative dietary survey data from Belgium, Denmark, France, Germany, The Netherlands, Poland, Spain and the United Kingdom. Dietary intake information was evaluated for intakes of Ca, Cu, I, Fe, Mg, K, Se, Zn and the vitamins A, B₁, B₂, B₆, B₁₂, C, D, E and folate. The mean and 5th percentile of the intake distributions were estimated for these countries, for a number of defined sex and age groups. The percentages of those with intakes below the lower reference nutrient intake and the estimated average requirement were calculated. Reference intakes were derived from the UK and Nordic Nutrition Recommendations. The impact of dietary supplement intake as well as inclusion of apparently low energy reporters on the estimates was evaluated. Except for vitamin D, the present study suggests that the current intakes of vitamins from foods lead to low risk of low intakes in all age and sex groups. For current minerals, the study suggests that the risk of low intakes is likely to appear more often in specific age groups. In spite of the limitations of the data, the present study provides valuable new information about micronutrient intakes across Europe and the likelihood of inadequacy country by country.

Iron, meat and health

This article is a summary of the publication "Iron and Health" by the Scientific Advisory Committee on Nutrition (SACN) to the U.K. Government (2010), which reviews the dietary intake of iron and the impact of different dietary patterns on the nutritional and health status of the U.K. population. It concludes that several uncertainties make it difficult to determine dose-response relationships or to confidently characterize the risks associated with iron deficiency or excess. The publication makes several recommendations concerning iron intakes from food, including meat, and from supplements, as well as recommendations for further research.

Development of a series of patient information leaflets for constipation using a range of cognitive interview techniques: LIFELAX

BACKGROUND

The aim of the LIFELAX randomised controlled trial (diet and lifestyle vs. laxatives in the management of chronic constipation) is to develop and evaluate a cost effective intervention to promote diet and lifestyle in the treatment and management of chronic constipation for older people in Primary Care. Constipation affects the quality of life in around 20% of older people in the community. In the 65 years plus population, a significant proportion of men and women both living in institutions (81% and 75% respectively) and free living (30% and 37% respectively) use laxatives. Approximately 42 million pounds is spent each year on prescribed laxatives in England in addition to laxatives purchased over the counter. Although bowel problems are often multifactorial, diet and lifestyle have an extremely important role in their management. This paper describes one aspect of the main study, the development and piloting of the Patient information leaflets (PILs).

METHODS

Following review of the literature and interviews with practitioners and patients, 8 PILs were designed on: constipation, activity, bowel health, fruit and vegetables, fibre, fluid, alternative therapies and laxatives. To check the patient's understanding of terms used in the PILS and the clarity and accessibility of the information understanding, cognitive interviews (CI) were used with nine patients (selected from 3 GP surgeries), aged > or = 55 years, who had received > or = 3 prescriptions of laxatives over 12 months. Interviews were recorded and transcribed.

RESULTS

Changes made following the CI process included the lay-out, words used (e.g. 'exercise' was changed to 'activity', 'gut motility' changed to 'bowel movement') and descriptions and examples were adapted to be more appropriate for the target population.

CONCLUSION

Pilot testing with CIs resulted in improvements in the PILs, which emphasises the need to pilot PILs with the target population before use. The techniques employed are relatively inexpensive and could be routinely used when preparing literature for research or clinical use including those intended for use with healthcare professionals and patients.

Dietary supplement use by community-living population in Japan: data from the National Institute for Longevity Sciences Longitudinal Study of Aging (NILS-LSA)

BACKGROUND

There are few studies about dietary supplement use and nutrient intake from these products in Japan. The purpose of this study was to clarify (1) the prevalence of dietary supplement use, (2) the characteristics of dietary supplement users, (3) nutrient intake from dietary supplements, and (4) the existence of dietary supplement users who took excessive nutrients from these products.

METHODS

To collect the information on dietary supplement use in the previous year and nutrient intake from these products, we conducted a self-administered dietary supplement frequency questionnaire. The subjects were 2,259 people aged 40-82 years. Dietary supplements were grouped into 8 major categories. A dietary supplement database was developed to estimate nutrient intake from these products. Excess users were defined as people who consumed more nutrient than the tolerable upper intake level of the Dietary Reference Intakes for Japanese.

RESULTS

In the previous year, 55 % of males and 61 % of females consumed dietary supplements. Dietary supplement use was especially prevalent in females, subjects who felt unhealthy, and subjects who were more careful of maintaining an appropriate weight, though the association was affected by the frequency of dietary supplement use. The most common dietary supplements were drink type in males and vitamins in females. Some nutrient values obtained from dietary supplements were higher than those from food. Excess users were found for intake of vitamin A, B₆, K, niacin, iron, and magnesium.

CONCLUSIONS

It is important to clarify dietary supplement use and to estimate nutrient intake from these products.

Allowing for variations in multivitamin supplement composition improves nutrient intake estimates for epidemiologic studies

Collecting detailed data on dietary supplement use is time-consuming for study participants and investigators, and this is particularly difficult for multivitamin use because of the many different formulations available. Therefore, many studies simply ask about the frequency of multivitamin use and assign default nutrient composition values to obtain nutrient intakes. Multivitamin supplements are important contributors to total nutrient intakes, but it is not known how default values affect the accuracy of intake estimation. In this study, nutrient intakes were calculated from multivitamins consumed by 26,735 multivitamin users who provided detailed information like product name(s) and frequency of use on a mailed questionnaire. We then recalculated the intakes, using 2 different assumptions about the composition of the multivitamin supplements: 1) a single default composition for all products; and 2) four default compositions, 1 for each subtype of multivitamin, i.e., one-a-day with minerals, one-a-day without minerals, B-complex or stress multivitamins, and antioxidant combinations. A total of 1246 different brands of multivitamins were reported and nutrient composition varied widely. Spearman correlation coefficient analyses, using the 4 default nutrient profiles compared with actual nutrient intakes, were >0.5 (P < 0.001) for 12 of 15 nutrients examined. However, correlations using the single default were lower, with only 5 correlations >0.5. Our findings suggest that a questionnaire designed to assess the composition profiles for 4 types of multivitamin products substantially improves the accuracy of nutrient-intake estimates over one that uses a single default nutrient profile for all multivitamin products.

Age as a determinant of nutritional status: a cross sectional study

BACKGROUND

Undenutrition is known to be prevalent and largely unrecognised in older patients; however, aberrations in indicators of nutritional status may simply reflect effects of age and/or functional disability.

OBJECTIVE

The aim of this study was to measure the effect, if any of age on nutritional status in older patients.

DESIGN

445 randomly selected hospitalised patients consented to nutritional status assessment derived from anthropometric, haematological, and biochemical data within 72 hours of admission. Nutritional status was compared between those age < 75 years and those aged 75 years or more. Using multiple regression models, we measured the association between age and nutritional assessment variables after adjusting for disability, chronic illness, medications, smoking and tissue inflammation.

RESULTS

Body weight, body mass index, mid-upper arm circumference, haemoglobin, serum albumin and plasma ascorbic acid were all significantly lower in people aged > or = 75 years compared with those < 75 years of age. Although riboflavin (vitamin B2), 25OH VitD3, red-cell folate and vitamin B12 concentrations were lower in those aged > or = 75 years, differences were not statistically significant. After adjusting for disability and co-morbidity in a multivariate analysis, age alone had a significant and independent effect on important anthropometric and biochemical nutritional assessment variables.

CONCLUSION

Increasing age is independently associated with poor nutritional status. This may partly explain the poor clinical outcome in older patients.

Effect of multivitamin and multimineral supplements on morbidity from infections in older people (MAVIS trial): pragmatic, randomised, double blind, placebo controlled trial

OBJECTIVE

To examine whether supplementation with multivitamins and multiminerals influences self reported days of infection, use of health services, and quality of life in people aged 65 or over.

DESIGN

Randomised, placebo controlled trial, with blinding of participants, outcome assessors, and investigators.

SETTING

Communities associated with six general practices in Grampian, Scotland.

PARTICIPANTS

910 men and women aged 65 or over who did not take vitamins or minerals.

INTERVENTIONS

Daily multivitamin and multimineral supplementation or placebo for one year.

MAIN OUTCOME MEASURES

Primary outcomes were contacts with primary care for infections, self reported days of infection, and quality of life. Secondary outcomes included antibiotic prescriptions, hospital admissions, adverse events, and compliance.

RESULTS

Supplementation did not significantly affect contacts with primary care and days of infection per person (incidence rate ratio 0.96, 95% confidence interval 0.78 to 1.19 and 1.07, 0.90 to 1.27). Quality of life was not affected by supplementation. No statistically significant findings were found for secondary outcomes or subgroups.

CONCLUSION

Routine multivitamin and multimineral supplementation of older people living at home does not affect self reported infection related morbidity.

TRIAL REGISTRATION

ISRCTN: 66376460.

Supplement use is associated with health status and health-related behaviors in the 1946 British birth cohort

Use of dietary supplements may be one of a number of health-related behaviors that cluster together. The current study investigated the underlying diet, health-related characteristics, and behaviors of users and nonusers of dietary supplements in a longitudinal study of health. Participants (n = 1776) completed a 5-d food diary including information on dietary supplement use (vitamins, minerals, and nutraceuticals) at age 53 y. Sociodemographic information and data on smoking, alcohol, and physical activity were obtained along with anthropometric measurements, blood pressure, and a blood sample (nonfasting subjects). A significantly greater percentage of women reported supplement use compared with men (45.1 vs. 25.2%). Supplement use was associated with lower BMI, lower waist circumference, higher plasma folate and plasma vitamin B-12 concentrations, nonsmoking, participation in physical activity, and nonmanual social class in women and with plasma folate concentrations and participation in physical activity in men. Nonsupplement users tended to be nonconsumers of breakfast cereals, fruit, fruit juice, yogurt, oily fish, and olive oil and had lower dietary intakes of potassium, magnesium, phosphorus, iron, and vitamin C even after adjustment for sociodemographic and behavioral factors. Overall, supplement users tended to differ from nonsupplement users on a range of health-related behaviors and health status indicators, although there were fewer significant associations in men. Similarly, dietary supplements users tended to have underlying diets that, were healthier and those taking supplements may be the least likely to need them. These results support the notion of a clustering of healthy behaviors and cardiovascular risk factors, particularly for women.

Association of dietary supplement use with specific micronutrient intakes among middle-aged American men and women: the INTERMAP Study

OBJECTIVE

To assess dietary supplement use and its association with micronutrient intakes and adequacy among 2,195 US men and women aged 40 to 59 years from eight diverse population samples surveyed by the International Population Study on Macronutrients and Blood Pressure.

DESIGN

Four 24-hour dietary recalls were collected, including information on dietary supplements. The Nutrition Data System (NDS) was used for nutrient analyses. Supplements not in NDS were classified separately (non-NDS). Intake of non-NDS supplements was documented. Participants were classified as not supplement users and supplement users, subclassified-due to concerns about nutritional value-as users of NDS supplements only (mostly vitamins and minerals) and users of non-NDS supplements (eg, botanicals, animal products, and enzymes). To assess effects of supplement use on micronutrient intake and adequacy, mean intakes from supplements, foods, and foods plus supplements were compared with Dietary Reference Intakes.

PARTICIPANTS

Two thousand one hundred ninety-five US participants; 1,136 used supplements.

STATISTICAL ANALYSES

Chi 2 tests, multivariate logistic regression, and means were used to assess differences in and factors related to supplement use and to determine dietary adequacy.

RESULTS

Supplement use was more common among women, older participants, more educated participants, and Asian Americans. Body mass index and current cigarette smoking were significantly and inversely associated with supplement use; past smoking and education were significantly and positively associated with supplement use. Intake from foods plus supplements was considerably higher than from foods alone for vitamins A, C, and E; niacin; folate; and iron.

CONCLUSIONS

Supplement use is common among middle-aged Americans and sizably increases daily intakes of several micronutrients. These data underscore the importance of dietary supplement assessment.

Serum vitamin B12 concentrations and atrophic gastritis in older New Zealanders

OBJECTIVE

To determine the serum vitamin B(12) status of older New Zealanders and to assess the impact of atrophic gastritis on vitamin B(12) status.

DESIGN

A cross-sectional nationally representative population-based survey.

METHOD

Serum vitamin B(12) concentrations were used to assess vitamin B(12) status. The presence and severity of atrophic gastritis was classified using serum pepsinogen I and II.

SUBJECTS

A total of 466 noninstitutionalized urban and rural dwelling New Zealanders aged 65 y or older who participated in the 1997 National Nutrition Survey.

RESULTS

The prevalence of deficient (<148 pmol/l) and marginal (148-221 pmol/l) serum vitamin B(12) concentrations was 12 and 28%, respectively. The prevalence of atrophic gastritis was 6.7% (severe 3.1%, mild-moderate 3.6%). While atrophic gastritis increased the relative risk (RR, 95% CI) of having a deficient or marginal serum vitamin B(12) concentration by 21-fold (6-67) and five-fold (1-17), respectively, those who had atrophic gastritis made up only 33 and 6% of the participants with deficient or marginal serum vitamin B(12) concentrations. An intake of vitamin B(12) from food that exceeded the recommended dietary allowance (2.4 mug/day) did not protect against deficient (RR 0.5; 95% CI: 0.2, 1.2) or marginal (RR 0.9; 95% CI: 0.5, 1.7) serum vitamin B(12) status. Vitamin B(12) supplement users had a reduced risk of having deficient and marginal vitamin B(12) status (RR 0.3; 95% CI: 0.1, 0.8).

CONCLUSIONS

There is a relatively high prevalence of deficient and marginal serum vitamin B(12) concentrations among older New Zealanders. However, the prevalence of atrophic gastritis was low in the New Zealand elderly compared with other surveys. Although atrophic gastritis was a risk factor for low vitamin B(12) status, it did not fully explain the prevalence of low serum vitamin B(12).

The validity of questionnaire-based micronutrient intake estimates is increased by including dietary supplement use in Swedish men

Although many validation studies of FFQ have been reported, only a few addressed the effect of inclusion of dietary supplement use on the validity of micronutrient estimates. The purpose of the present study was to assess reproducibility and validity of a self-administered FFQ, intended to measure total nutrient intake from diet and from dietary supplements, in a random population-based sample of 248 middle-aged and elderly men (40-74 y old) in central Sweden. Fourteen 24-h recall interviews were used as the reference method. Participants were telephoned about once a month for 1 y, covering every day of the week, twice in random order. Spearman correlation coefficients increased 13% (from 0.49 to 0.62), between FFQ-based micronutrient estimates and the fourteen 24-h recall interviews (reference method) when supplement use was included. Correct classification into highest quintiles was also improved by 14% (from 37 to 51%). There were no differences in mean intraclass correlation coefficients for 1-y reproducibility between total micronutrient intake and micronutrients from foods only. The increase in the validity of micronutrient estimates due to inclusion of supplements in nutrient intake assessment has important implications for sample size in epidemiologic studies. Because a dramatic increase in dietary supplement use has occurred in recent decades in many countries, the issue of including supplements in dietary assessment should be of highest priority in nutritional epidemiologic studies of chronic diseases.

In a population study, can parathyroid hormone aid the definition of adequate vitamin D status? A study of people aged 65 years and over from the British National Diet and Nutrition Survey

The British National Diet and Nutrition Survey of people aged 65 years and over in 1994-5 provided nationally representative estimates of food and nutrient intakes and biochemical status indices. In a further analysis study, parathyroid hormone (PTH) concentrations were measured in plasma samples from 773 subjects and were analyzed with the existing data on vitamin D intake, plasma 25-hydroxyvitamin D (25OHD), total plasma calcium and albumin. As predicted, a strong inverse relationship was observed between PTH and 25OHD. In the free-living respondents aged 65-84 years (n=507) there was a continuous decline in PTH with increasing 25OHD and no plateau, whereas in free-living people aged 85+ years (n=86) there was a significant deviation from a simple inverse relationship, with unexpectedly high PTH values in some people with satisfactory 25OHD status. There was a relationship between both PTH (inverse) and plasma 25OHD (direct) with calcium intake. A direct relationship between 25OHD and total plasma calcium was not significant when calcium was corrected for albumin. Geographically, 25OHD, and to a lesser extent PTH, exhibited a north-south gradient, and 25OHD was associated with self-reported health status. Both 25OHD and PTH were associated with self-reported physical activity. Low calcium intake and 25OHD was associated with receipt of state benefits. The relationship between plasma 25OHD and vitamin D intake revealed a striking seasonal cycle. 25OHD was strongly influenced by vitamin D intake in the winter in free-living subjects, but this was not observed in the summer. In people living in institutions such as nursing homes, who are less likely to be exposed to sunlight throughout the year, plasma 25OHD levels were lower throughout the year.

Micronutrients: highlights and research challenges from the 1994-5 National Diet and Nutrition Survey of people aged 65 years and over

The aims of the National Diet and Nutrition Survey series are summarized, and the new National Diet and Nutrition Survey of people aged 65 years and over is explored, with particular emphasis on micronutrient intakes and status indices. Mean nutrient intakes were generally satisfactory for most micronutrients, but intakes of vitamin D, Mg, K and Cu were low. Intakes of vitamin D were far below the reference nutrient intake for people aged 65 years and over, and there was also biochemical evidence of vitamin D deficiency, for 8% of free-living and 37% of institution participants, attributed partly to limited exposure to sunlight. A substantial proportion of people living in institutions had inadequate biochemical status indices, notably for vitamin C, Fe and folate. Relationships between intake and status were close for vitamins. Mineral intakes did not correlate well with currently used status indices. Some intakes and indices, especially those of vitamin C, carotenoids, Na and K, were strongly correlated with socio-economic status and with north-south gradients in Britain. Future research challenges should address the functional and health significance of low intakes and sub-optimal biochemical indices for certain micronutrients, especially for people living in institutions; the shortcomings of mineral status indices especially as indicators of mineral intake; the social and geographical inequalities of micronutrient intakes and status, and why micronutrient status deteriorates with increasing age. The answers to these questions will help to define the characteristics of nutritional risk for older people in Britain, and to clarify future needs for education and intervention.