The present study identified dietary patterns (DP) and analyse their association with household composition. This is a cross-sectional school-based study, with a nationally representative sample of Brazilian adolescent students, aged 11–19 years, with data from National School Health Survey (n 102 072). Food consumption was obtained through the weekly frequency of consumption of food markers, and the confirmatory factor analysis was applied to examine the latent variables ‘Healthy’ (beans, legumes/vegetables and fresh fruit/fruit salad) and ‘Unhealthy’ (ultra-processed foods, sweets, soft drinks and snacks) DP. The association between household composition and DP was estimated considering lives with both parents as reference category. Among adolescents aged 11–14 years, adherence to healthy DP was lower for boys who lived only with mother (β = –2·1), and boys (β = –4·9) and girls (β = –4·5) who lived without any parents. Adherence to unhealthy DP was higher among boys (β = 7·6) and girls (β = 6·0) who lived only with mother, and boys (β = 4·6) and girls (β = 5·3) who lived only with father. For older adolescents (aged 15–19 years), adherence to the unhealthy DP was higher among boys who lived only with mother (β = 3·9) or only with father (β = 5·3) and girls who lived only with mother (β = 6·3). Adherence to healthy DP was lower among girls who lived only with father (β = –9·0). Thus, adolescents who lived in single-parent households had lower adherence to healthy DP and greater adherence to unhealthy DP. Among younger adolescents of both sexes, living without any parent contributed to lower adherence to healthy DP.

Cognitive decline is a public health problem for the world’s ageing population. This study was to evaluate the relationships between serum Fe, blood Pb, Cd, Hg, Se and Mn and cognitive decline in elderly Americans. Data of this cross-sectional study were extracted from the National Health and Nutritional Examination Survey (NHANES 2011–2014). Cognitive performance was measured by the Consortium to Establish a Registry for Alzheimer’s Disease (CERAD), Animal Fluency and Digit Symbol Substitution Test (DSST) tests. Weighted univariable and multivariate logistic regression analyses were used to assess the associations between six trace elements and low cognitive performance. Subgroup analyses based on diabetes and hypertension history were further assessed the associations. A total of 2002 adults over 60 years old were included. After adjusting covariates, elevated serum Fe levels were associated with the decreased risk of low cognitive performance, especially in the elderly without diabetes history and with hypertension history. High blood Cd levels were associated with the high odds of low cognitive performance in old adults with diabetes and hypertension history. Elevated blood Mn levels were connected with low cognitive performance in old hypertensive people. High blood Pb levels were related to the high odds of low cognitive performance, especially in the elderly without diabetes and hypertension history. High blood Se levels were linked to the decreased risk of low cognitive performance in all the elderly. Appropriate Fe, Se supplementation and Fe-, Se-rich foods intake, while reducing exposure to Pb, Cd and Mn may be beneficial for cognitive function in the elderly.

It is difficult to easily estimate skeletal muscle (SM) volume in children. We aimed to develop regression-based prediction equations to estimate the total body and regional SM volume using calliper measurements of skinfold thickness and limb circumference and to investigate the validity of these equations. In total, 142 healthy, prepubertal, Japanese children, aged 6–12 years, were divided into two groups: the model development group (sixty boys, thirty-eight girls) and the validation group (twenty-six boys, eighteen girls). Contiguous magnetic resonance images were obtained from the first cervical vertebra to the ankle joints as reference data. SM volume was calculated from the summation of the digitised cross-sectional areas. Limb and waist circumferences were measured at mid-upper arm, mid-thigh, maximal calf and at the level of umbilicus. Each girth was corrected for subcutaneous adipose tissue thickness, as estimated by skinfold thickness measurements. Skinfold thickness was measured at the posterior upper arm, anterior thigh, medial calf and lateral to the umbilicus, using callipers. Significant correlations were observed between the site-matched SM volume, measured by MRI, and each corrected girth × standing height value in the model development group. When these SM volume prediction equations were applied to the validation group, the measured total body and regional SM volume were similar to the predicted values. These results suggest that the anthropometric prediction equations developed in this study provide reliable information about the total and regional SM volume in prepubertal Japanese children, with varying degrees of estimation accuracy for each region.

Vegetarians have less hypertension, diabetes mellitus and obesity, hence possibly lower risk of congestive heart failure (HF). We studied associations between vegetarian diets and echocardiographic markers of stage B HF. In a cross-sectional study, dietary pattern was ascertained by a validated FFQ. Echocardiograms were interpreted using standardised criteria. Participants were free-living subjects in Southern California who were older Adventist Health Study-2 cohort members. After exclusions, 133 subjects aged >60 years were enrolled. Their mean age was 72·7 (sd 8·7) years, 48·1 % were female, 32 % were African American and 71 % were vegetarian. Non-vegetarians had higher body weight (80·3 (sd 15·17) kg v. 71·3 (sd 16·2), P < 0·005), body surface area (1·92 (sd 0·24) m2 v. 1·81 (sd 0·22) m2, P = 0·01) and prevalence of hypertension (63 % v. 47 %, P = 0·10). Adjusting for age, sex, race and physical activity, it is found that vegetarians had greater echocardiographic mitral annular e’ velocity (a measure of left ventricular (LV) relaxation) 7·44 v. 6·48 (non-vegetarian) cm/s (P = 0·011) and a yet greater contrast when vegans (7·66 cm/s, P = 0·011) were the group of interest. The ratio mid-to-late-diastolic mitral flow velocity (E/A) was also higher in vegans compared with non-vegetarians (1·02 and 0·84, respectively, P = 0·008). Mediation analyses suggested these associations may be partly related to higher blood pressures and BMI in the non-vegetarians. We conclude that vegetarians, especially vegans, appear to have better LV relaxation and fewer diastolic abnormalities than others. As dietary exposure is modifiable, one may speculate pending further investigation about the potential for reduction of stage B HF and later mortality.

Changes between diet quality and health-related quality of life (HR-QoL) over 12 years were examined in men and women, in 2844 adults (46 % males; mean age 47·3 (sd 9·7) years) from the Australian Diabetes, Obesity and Lifestyle study with data at baseline, 5 and 12 years. Dietary intake was assessed with a seventy-four-item FFQ. Diet quality was estimated with the Dietary Guideline Index, Mediterranean-Dietary Approaches to Stop Hypertension Diet Intervention for Neurological Delay Index (MIND) and Dietary Inflammatory Index. HR-QoL in terms of global, physical component summary (PCS) and mental component summary (MCS) was assessed with the Short-Form Health Survey-36. Fixed effects regression models adjusted for confounders were performed. Mean MCS increased from baseline (49·0, sd 9·3) to year 12 (50·7, sd 9·1), whereas mean PCS decreased from baseline (51·7, sd 7·4) to year 12 (49·5, sd 8·6). For the total sample, an improvement in MIND was associated with an improvement in global QoL (β = 0·28, 95 % CI (0·007, 0·55)). In men, an improvement in MIND was associated with an improvement in global QoL (β = 0·28, 95 % CI (0·0004, 0·55)). In women, improvement in MIND was associated with improvements in global QoL (β = 0·62 95 % CI (0·38, 0·85)), MCS (β = 0·75, 95 % CI (0·29, 1·22)) and PCS (β = 0·75, 95 % CI (0·29, 1·22)). Positive changes in diet quality were associated with broad improvements in HR-QoL, and most benefits were observed in women when compared to men. These findings support the need for strategies to assist the population in consuming healthy dietary patterns to lead to improvements in HR-QoL.

Selenium (Se) is essential for selenoprotein synthesis, being thus important for immune and thyroid function, and for antioxidant defence. Some studies have shown that low levels of Se may associate with hypertensive disorders of pregnancy (HDP). Nevertheless, evidence supporting Se supplementation in pregnant or childbearing-age women is still lacking. In this context, this work aimed to systematically review the most recent scientific evidence to understand the relationship between Se levels and HDP. We performed a systematic review (protocol number: CRD42022310424) with literature of the last decade. PubMed, Scopus, Web of Science, registers and grey literature were searched to identify studies reporting measurement of Se levels in normotensive and hypertensive pregnant women (supplemented or not with Se). Study quality was assessed using the National Heart, Lung, and Blood Institute Study Quality Assessment Tools. Among the thirty included studies, a majority, 61 % (n 19) of the ‘good’ or ‘fair’ studies, reported a negative association between Se and HDP, and some studies, 39 % (n 11) of the ‘good’ or ‘fair’ studies, reported a lack of association. This review provides an important amount of quality evidence suggesting that low Se levels associate with the occurrence of HDP. Nevertheless, the gathered information is not enough to underlie a recommendation for Se supplementation in pregnancy to protect against HDP. Thus, this review emphasises the need for further well-designed randomised controlled trials that may provide blunt evidence regarding the benefits of Se supplementation during pregnancy.

Iodine is a vital trace element in the human body and is associated with several important coronary artery disease (CAD) risk factors. We aimed to explore the correlation between urinary iodine concentration (UIC) and CAD. Data from 15 793 US adults in the National Health and Nutrition Examination Survey (2003–2018) were analysed. We conducted multivariable logistic regression models and fitted smoothing curves to study the correlation between UIC and CAD. Furthermore, we performed subgroup analysis to investigate possible effect modifiers between them. We found a J-shaped association between UIC and CAD, with an inflection point at Lg UIC = 2·65 μg/l. This result indicated a neutral association (OR 0·89; 95 % CI 0·68, 1·16) between UIC and CAD as Lg UIC < 2·65 μg/l, but the per natural Lg [UIC] increment was OR 2·29; 95 % CI 1·53, 3·43 as Lg UIC ≥ 2·65 μg/l. An interaction between diabetes and UIC might exist. The increase in UIC results in an increase in CAD prevalence (OR 1·84, 95 % CI 1·32, 2·58) in diabetes but results in little to no difference in non-diabetes (OR 0·98, 95 % CI 0·77, 1·25). The J-shaped correlation between UIC and CAD and the interaction between diabetes and UIC should be confirmed in a prospective study with a series of UIC measurements. If excessive iodine precedes CAD, then this new finding could guide clinical practice and prevent iodine deficiency from being overcorrected.

Improving diet quality is recognised as a double-duty action that can simultaneously address multiple forms of malnutrition. This study aimed to assess diet quality among non-pregnant non-lactating women of reproductive age (WRA) in Addis Ababa, Ethiopia. A 1-d quantitative 24 h recall was conducted among 653 non-pregnant/non-lactating women. Diet quality, assessed using the women dietary diversity score (WDDS), the Global Diet Quality Score (GDQS) and the Nova 4 classification reflecting consumption of ultra-processed foods (UPF), was compared. The proportion that meets the minimum dietary diversity for women (MDD-W) was estimated. The average MDD-W score was 2·6 (sd 0·9), with only 3 % of women meeting the MDD-W (≥ 5 food groups). Consumption of wholegrain and legumes was high, but UPF were also consumed by 9 % of the women. GDQS was positively associated with WDDS, age and skipping breakfast and was negatively associated with eating out of home and UPF consumption (P < 0·05). The multivariate regression model showed that GDQS (total) was not associated with wealth but was significantly associated with both UPF and WDDS (P < 0·001). Unlike UPF and WDDS alone, GDQS was able to predict both nutrient adequacy and unhealthy dietary practices. The diet quality of WRA in Addis Ababa is low in diversity, possibly exposing them to higher risk of nutrient inadequacy and non-communicable diseases as reflected by the low GDQS. Understanding what drives food and dietary choices in urban settings is urgently needed.

An abnormal Zn status has been suggested to play a role in the pathogenesis of type 2 diabetes. However, epidemiological studies of the relationship between plasma Zn concentrations and diabetes are sparse and inconclusive. We aimed to investigate the association between plasma Zn concentrations and glycaemic markers (fasting glucose, 2-h glucose and homeostatic model assessment of insulin resistance) in rural and urban Cameroon. We studied 596 healthy adults (63·3 % women) aged 25–55 years in a population-based cross-sectional study. The mean plasma Zn concentration was 13·7 ± 2·7 µmol/L overall, with higher levels in men (14·4 ± 2·9 µmol/l) than in women (13·2 ± 2·6 µmol/l), P-value < 0·0001. There was an inverse relationship between tertiles of plasma Zn and 2-h glucose concentrations (P-value for linear trend = 0·002). The difference in 2-h glucose between those in the highest tertile of plasma Zn compared to the lowest was −0·63 (95 % CI − 1·02, −0·23) mmol/l. This remained significant after adjusting for age, sex, smoking status, alcohol intake, education level, area of residence, adiposity and objectively measured physical activity −0·43(–0·82, −0·04). Similar inverse associations were observed between plasma Zn concentrations and fasting glucose and homeostatic model assessment of insulin resistance when adjusted for socio-demographic and health-related behavioural characteristics. The current findings of an inverse association between plasma Zn concentrations and several markers of glucose homeostasis, together with growing evidence from intervention studies, suggest a role for Zn in glucose metabolism. If supported by further evidence, strategies to improve Zn status in populations may provide a cheap public health prevention approach for diabetes.

Inadequate protein intake and lack of micronutrients may affect neurodevelopment in infants. This randomised controlled trial was conducted to measure the effect of two milk–cereal mixes with modest and high amounts of protein and enriched with multiple micronutrients, given between 6 and 12 months, on cognitive, language, motor and behavioural scores at 12 and 24 months of age, compared with no-supplementation. The two supplements were also compared with each other. The study was conducted in urban Delhi, India, and the infants were randomised in a 1:1:1 ratio to the three study groups. At 12 and 24 months of age, 1134 and 1214 children were available, respectively. At 12 months of age, compared with no-supplement group, an increase in the motor scores (mean difference, MD 1·52, 95 % CI: 0·28, 2·75) and a decrease in the infant temperament scores (MD − 2·76, 95 % CI: −4·23, −1·29) in the modest-protein group was observed. Those in the high-protein group had lower socio-emotional scores (MD − 1·40, 95 % CI: −2·43, −0·37) and higher scores on Infant Temperament Scale (MD 2·05, 95 % CI: 0·62, 3·48) when compared with modest-protein group. At 24 months, no significant differences in any of the neurodevelopment scores between the three study groups was found. In conclusion, supplementation with modest amount of protein and multiple micronutrients may lead to short-term small improvements in motor function and infant temperament. There appears no advantage of supplementing with high protein, rather negative effects on infant behaviour were observed

Vegan and vegetarian diets are widely supported and adopted, but individuals following such diets remain at greater risk of iodine deficiency. This systematic review and meta-analysis was conducted to assess the iodine intake and status in adults following a vegan or vegetarian diet in the modern day. A systematic review and quality assessment were conducted from October 2020 to December 2022 according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidance. Studies were identified in Ovid MEDLINE, Web of Science, PubMed, and Scopus. Eleven articles were eligible for review containing 4421 adults (aged ≥ 18 years). Vegan groups had the lowest median urinary iodine concentration (mUIC) (12·2/l). None of the dietary groups had mUIC within the optimal range for iodine status (100–200 µg/l) (WHO). Vegan diets had the poorest iodine intake (17·3 µg/d) and were strongly associated with lower iodine intake (P = < 0·001) compared with omnivorous diets. Lower intake in vegan diets was influenced by sex (P = 0·007), the presence of voluntary or absence of Universal Salt Iodisation (USI) programmes (P = 0·01 & P = < 0·001), and living in a country with adequate iodine nutrition (P = < 0·001). Vegetarians and particularly vegans living in countries with no current USI programme continue to have increased risk of low iodine status, iodine deficiency and inadequate iodine intake. Further research into the usefulness of mandatory fortification of vegan appropriate foods is required.

The present study aimed to determine the prevalence of adiposity-based chronic disease (ABCD) and its association with anthropometric indices in the Mexican population. A cross-sectional study was conducted in 514 adults seen at a clinical research unit. The American Association of Clinical Endocrinology/AACE/ACE criteria were used to diagnose ABCD by first identifying subjects with BMI ≥ 25 kg/m2 and those with BMI of 23–24·9 kg/m2 and waist circumference ≥ 80 cm in women or ≥ 90 cm in men. The presence of metabolic and clinical complications associated with adiposity, such as factors related to metabolic syndrome, prediabetes, type 2 diabetes, dyslipidaemia and arterial hypertension, were subsequently evaluated. Anthropometric indices related to cardiometabolic risk factors were then determined. The results showed the prevalence of ABCD was 87·4 % in total, 91·5 % in men and 86 % in women. The prevalence of ABCD stage 0 was 2·4 %, stage 1 was 33·7 % and stage 2 was 51·3 %. The prevalence of obesity according to BMI was 57·6 %. The waist/hip circumference index (prevalence ratio (PR) = 7·57; 95 % CI 1·52, 37·5) and the conicity index (PR = 3·46; 95 % CI 1·34, 8·93) were better predictors of ABCD, while appendicular skeletal mass % and skeletal muscle mass % decreased the risk of developing ABCD (PR = 0·93; 95 % CI 0·90, 0·96; and PR = 0·95; 95 % CI 0·93, 0·98). In conclusion, the prevalence of ABCD in our study was 87·4 %. This prevalence increased with age. It is important to emphasise that one out of two subjects had severe obesity-related complications (ABCD stage 2).

The identification of somatic growth, through reference curves, can be used to create strategies and public policies to reduce public health problems such as malnutrition and obesity and to identify underweight, overweight and obesity. The purpose of this systematic review was to identify studies providing reference growth curves for weight status in children and adolescents. A systematic search was conducted in eight databases and in gray literature (Google scholar). To assess the risk of bias/methodological quality of studies, the National Institutes of Health (NIH) Quality Assessment Tool for Observational Cohort and Cross-sectional Studies (NHLBI) was used. Overall, 86 studies that met the inclusion criteria were included. Through the values   of reference growth curves for the identification of underweight, overweight and obesity, it was possible to verify that there is great variability among percentiles for the identification of underweight, overweight and obesity. The most prevalent percentiles for underweight were P3 and P5; for overweight, the most prevalent was P85 and the most prevalent percentiles for obesity were P95 and P97. The most prevalent anthropometric indicators were Body Mass Index (BMI), Waist Circumference (WC), Body Mass (BM) for age and height for age. Conclusion: Such data can demonstrate that the optimal growth must be reached, through the standard growth curves, but that the reference curves demonstrate a cut of the population growth, raising possible variables that can influence the optimal growth, such as an increase in the practice of physical activities and an awareness of proper nutrition.

With the recent growing interest in improving fruit and vegetable intake for better health and limited research resources in many settings, simple-to-administer and low-priced indicators are essential tools for monitoring fruit and vegetable intake at the population level. A potential candidate indicator is the fruit and vegetable component of the Global Dietary Recommendation score (FV-GDR) based on data collected using the Diet Quality Questionnaire (DQQ). We investigated the relative validity of FV-GDR collected with the DQQ to measure fruit and vegetable intake by comparison with a 24-h recall (24hR) as a reference collected from 620 Vietnamese and 630 Nigerian adults in 2021. We found proportional differences in the prevalence of intake of vitamin A-rich vegetables, other vegetables and other fruits in Vietnam and all vegetable food groups in Nigeria. In both countries, we found a small difference in the total FV-GDR from DQQ compared with the 24hR, and the percentage of agreement between the two methods was quite high for the majority of the food groups. The FV-GDR calculated from the DQQ correlated with the actual intake, although less strongly than the FV-GDR from 24hR. The DQQ is a promising low-burden, low-cost and simple tool to calculate FV-GDR and to monitor fruit and vegetable consumption at the population level. This provides the possibility of evaluating an important aspect of diet quality in low-resource settings.

Anaemia is characterised by low hemoglobin (Hb) concentration. Despite being a public health concern in Ethiopia, the role of micronutrients and non-nutritional factors as a determinant of Hb concentrations has been inadequately explored. This study focused on the assessment of serum micronutrient and Hb concentrations and a range of non-nutritional factors, to evaluate their associations with the risk of anaemia among the Ethiopian population (n 2046). It also explored the mediation effect of Zn on the relation between se and Hb. Bivariate and multivariate regression analyses were performed to identify the relationship between serum micronutrients concentration, inflammation biomarkers, nutritional status, presence of parasitic infection and socio-demographic factors with Hb concentration (n 2046). Sobel–Goodman test was applied to investigate the mediation of Zn on relations between serum se and Hb. In total, 18·6 % of participants were anaemic, 5·8 % had iron deficiency (ID), 2·6 % had ID anaemia and 0·6 % had tissue ID. Younger age, household head illiteracy and low serum concentrations of ferritin, Co, Cu and folate were associated with anaemia. Serum se had an indirect effect that was mediated by Zn, with a significant effect of se on Zn (P < 0·001) and Zn on Hb (P < 0·001). The findings of this study suggest the need for designing a multi-sectorial intervention to address anaemia based on demographic group.

The study aimed to explore the relationships of skeletal muscle mass with disease severity in metabolic-associated fatty liver disease (MAFLD) patients with different methods. Consecutive subjects undergoing bioelectrical impedance analysis were included. The steatosis grade and liver fibrosis were evaluated by MRI-derived proton density fat fraction and two-dimensional shear wave elastography. The appendicular skeletal muscle mass (ASM) was adjusted by height2 (ASM/H2), weight (ASM/W) and BMI (ASM/BMI). Overall, 2223 subjects (50·5 %, MAFLD; 46·9 %, male) were included, with the mean age 37·4 ± 10·6 years. In multivariate logistic regression analysis, the subjects with the lowest quartile (Q1) of ASM/W or ASM/BMI had higher risk ratios for MAFLD (OR (95 % CI) in male: 2·57 (1·35, 4·89), 2·11(1·22, 3·64); in female: 4·85 (2·33, 10·01), 4·81 (2·52, 9·16), all P < 0·05, all for Q1 v. Q4). The MAFLD patients with lower quartiles of ASM/W had the higher risk OR for insulin resistance (IR), both in male and female (2·14 (1·16, 3·97), 4·26 (1·29, 14·02) for Q4 v. Q1, both P < 0·05). While the significant OR were not observed when ASM/H2 and ASM/BMI were used. There were significant dose-dependent associations between decreased ASM/W as well as ASM/BMI and moderate–severe steatosis (2·85(1·54, 5·29), 1·90(1·09, 3·31), both P < 0·05) in male MAFLD patients. In conclusion, ASM/W is superior to ASM/H2 and ASM/BMI in predicting the degree of MAFLD. A lower ASM/W is associated with IR and moderate–severe steatosis in non-elderly male MAFLD.

Although ultra-processed foods represent more than half of the total energy consumed by the UK population, little is known about the trend in food consumption considering the degree of food processing. We evaluated the trends of the dietary share of foods categorised according to the NOVA classification in a historical series (2018–2019) among the UK population. Data were acquired from the NDNS, a survey that collects diet information through a 4-d food record. We used adjusted linear regression to estimate the dietary participation of NOVA groups and evaluated the linear trends over the years. From 2008 to 2019, we observed a significant increase in the energy share of culinary ingredients (from 3·7 to 4·9 % of the total energy consumed; P-trend = 0·001), especially for butter and oils; and reduction of processed foods (from 9·6 to 8·6 %; P-trend = 0·002), especially for beer and wine. Unprocessed or minimally processed foods (≅30 %, P-trend = 0·505) and ultra-processed foods (≅56 %, P-trend = 0·580) presented no significant change. However, changes in the consumption of some subgroups are noteworthy, such as the reduction in the energy share of red meat, sausages and other reconstituted meat products as well as the increase of fruits, ready meals, breakfast cereals, cookies, pastries, buns and cakes. Regarding the socio-demographic characteristics, no interaction was observed with the trend of the four NOVA groups. From 2008 to 2019 was observed a significant increase in culinary ingredients and a reduction in processed food. Furthermore, it sheds light on the high share of ultra-processed foods in the contemporary British diet.

This was a longitudinal study utilising the Irish Longitudinal Study on Ageing (n 3849 aged ≥ 50 years) and investigated the relationship between blood plasma folate and B12 levels at baseline (wave 1) and incident depressive symptoms at 2 and 4 years (waves 2 and 3). A score ≥ 9 on the Center for Epidemiological Studies Depression Scale-8 at wave 2 or 3 was indicative of incident depressive symptoms. B12 status profiles (pmol/l) were defined as < 185, deficient low; 185 to < 258, low normal; > 258–601, normal and > 601 high. Folate status profiles (nmol/l) were defined as ≤ 10·0, deficient low; > 10–23·0, low normal; > 23·0–45·0, normal; >45·0, high. Logistic regression models were used to analyse the longitudinal associations. Both B12 and folate plasma concentrations were lower in the group with incident depressive symptoms v. non-depressed (folate: 21·4 v. 25·1 nmol/l; P = 0·0003; B12:315·7 v. 335·9 pmol/l; P = 0·0148). Regression models demonstrated that participants with deficient-low B12 status at baseline had a significantly higher likelihood of incident depression 4 years later (OR 1·51, 95 % CI 1·01, 2·27, P = 0·043). This finding remained robust after controlling for relevant covariates. No associations of folate status with incident depression were observed. Older adults with deficient-low B12 status had a 51 % increased likelihood of developing depressive symptoms over 4 years. The findings highlight the need to further explore the low-cost benefits of optimising vitamin B12 status for depression in older adults.