169Folic acid intake and dementia - a 27-year global longitudinal study

Abstract Background Folate deficiency increases serum homocysteine and may cause cognitive impairment. However, there have been no international longitudinal studies that examined the association between folic acid intake and dementia. We investigated the longitudinal association between folate intake and the prevalence of dementia using global data during 27 years. Methods Prevalence of Alzheimer’s disease and other dementias and folic acid intake by country were obtained from the Global Burden of Disease (GBD) 2017 database. The longitudinal associations between folic acid intake and prevalence of dementia was examined using linear mixed effect model during 27 years from 1990 to 2017 in 151countries with populations of 1 million or greater. The effects of folic acid, year and interaction of folic acid and year were estimated controlling for covariates including socio-economic variables and life-style variables. Results Fixed effects of folic acid was highly significant (mean and SE; -33.1±7.1, p < 0.001) and interaction of folic acid and survey year was also significant (0.90±0.13, p < 0.001). Slope of folic acid for dementia prevalence was significant in 1990 and the slope has decreased with the year and has become not significant after 2011. Conclusions Folic acid was associated with the prevalence of dementia, but weakened over the years. Key messages Although folic acid intake has been associated with the of dementia, the risk of dementia may be increasingly related to factors other than nutrition.

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Folic acid food fortification prevents inadequate folate intake among preschoolers from Ontario

Public Health Nutrition ◽

10.1017/s1368980008004667 ◽

2009 ◽

Vol 12 (9) ◽

pp. 1548-1555 ◽

Cited By ~ 5

Author(s):

Kathleen Hennessy-Priest ◽

Jill Mustard ◽

Heather Keller ◽

Lee Rysdale ◽

Joanne Beyers ◽

...

Keyword(s):

Folic Acid ◽

Public Health Intervention ◽

Folate Intake ◽

Food Fortification ◽

Folic Acid Intake ◽

Cross Sectional ◽

Dietary Folate ◽

Supplement Use ◽

Acid Intake ◽

Fortified Food

AbstractObjectiveFolic acid food fortification has successfully reduced neural tube defect-affected pregnancies across Canada. The effect of this uncontrolled public health intervention on folate intake among Canadian children is, however, unknown. Our objectives were to determine folic acid intake from food fortification and whether fortification promoted adequate folate intakes, and to describe folic acid-fortified food usage among Ontario preschoolers.DesignCross-sectional data were used from the NutriSTEP™ validation project with preschoolers recruited using convenience sampling. Mean daily total folate and folic acid intakes were estimated from 3 d food records, which included multivitamin supplement use. Comparisons were made to Dietary Reference Intakes, accounting for and excluding fortificant folic acid, to determine the prevalence of inadequate and excessive intakes.SettingCanada.SubjectsTwo hundred and fifty-four preschoolers (aged 3–5 years).ResultsAll participants (130 girls, 124 boys) ate folic acid-fortified foods and 30 % (n76) used folic acid-containing supplements. Mean (se) fortificant folic acid intake was 83 (2) μg/d, which contributed 30 % and 50 % to total folate intake for supplement users and non-users, respectively. The prevalence of total folate intakes below the Estimated Average Requirement was <1 %; however, excluding fortificant folic acid, the prevalence was 32 %, 54 % and 47 % for 3-, 4- and 5-year-olds, respectively. The overall prevalence of folic acid (fortificant and supplemental) intakes above the Tolerable Upper Intake Level was 2 % (7 % among supplement users).ConclusionsFolic acid food fortification promotes dietary folate adequacy and did not appear to result in excessive folic acid intake unless folic acid-containing supplements were consumed.

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Dietary intake of folate by adolescents and the potential effect of flour fortification with folic acid

British Journal Of Nutrition ◽

10.1079/bjn2001425 ◽

2001 ◽

Vol 86 (4) ◽

pp. 529-534 ◽

Cited By ~ 7

Author(s):

P. J. Moynihan ◽

A. J. Rugg-Gunn ◽

T. J. Butler ◽

A. J. Adamson

Keyword(s):

Folic Acid ◽

Dietary Intake ◽

Potential Effect ◽

Folate Intake ◽

Folic Acid Intake ◽

Folic Acid Fortification ◽

Acid Intake ◽

Department Of Health ◽

White Flour ◽

The Uk

The UK Department of Health recently recommended that flour be fortified with folic acid, at 2400 μg/kg. The objectives of the present paper were: to determine the consequence of this on folic acid intake of adolescents; to determine the level of fortification necessary to achieve an intake of 400 μg/d in adolescent girls (the amount recommended periconceptionally); to estimate the consequence of fortification on folic acid intake of high flour consumers; and to report on folate intake of adolescents. Dietary intake of folate and flour were determined by analysis of an existing database of the diets of 379 English adolescents. The folic acid intake that would result from white flour fortification with folic acid at 2400 μg/kg was determined and the level of folic acid fortification necessary to achieve an intake of 400 μg/d in girls from this source was also calculated. Without flour fortification, 6·9 % of girls failed to reach the UK lower reference nutrient intake for total folate. Fortification of white flour with folic acid at 2400 μg/kg would result in an additional folic acid intake of 191(SEM 6) μg/d in girls. To ensure 97 % of girls received 400 μg/d from white flour, white flour would need to be fortified at a level of 10 430 μg/kg, resulting in intakes of 1260 μg/d from flour in the highest (97·5 centile) female white flour consumers and 1422 μg/d from flour in the highest (97·5 centile) male white flour consumers.

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Knowledge gaps in understanding the metabolic and clinical effects of excess folates/folic acid: a summary, and perspectives, from an NIH workshop

American Journal of Clinical Nutrition ◽

10.1093/ajcn/nqaa259 ◽

2020 ◽

Vol 112 (5) ◽

pp. 1390-1403

Author(s):

Padma Maruvada ◽

Patrick J Stover ◽

Joel B Mason ◽

Regan L Bailey ◽

Cindy D Davis ◽

...

Keyword(s):

Folic Acid ◽

Adverse Effects ◽

Folate Intake ◽

Vitamin B ◽

Clinical Effects ◽

Folic Acid Intake ◽

Folate Status ◽

Acid Intake ◽

Adverse Health ◽

Vitamin B 12

ABSTRACT Folate, an essential nutrient found naturally in foods in a reduced form, is present in dietary supplements and fortified foods in an oxidized synthetic form (folic acid). There is widespread agreement that maintaining adequate folate status is critical to prevent diseases due to folate inadequacy (e.g., anemia, birth defects, and cancer). However, there are concerns of potential adverse effects of excess folic acid intake and/or elevated folate status, with the original concern focused on exacerbation of clinical effects of vitamin B-12 deficiency and its role in neurocognitive health. More recently, animal and observational studies have suggested potential adverse effects on cancer risk, birth outcomes, and other diseases. Observations indicating adverse effects from excess folic acid intake, elevated folate status, and unmetabolized folic acid (UMFA) remain inconclusive; the data do not provide the evidence needed to affect public health recommendations. Moreover, strong biological and mechanistic premises connecting elevated folic acid intake, UMFA, and/or high folate status to adverse health outcomes are lacking. However, the body of evidence on potential adverse health outcomes indicates the need for comprehensive research to clarify these issues and bridge knowledge gaps. Three key research questions encompass the additional research needed to establish whether high folic acid or total folate intake contributes to disease risk. 1) Does UMFA affect biological pathways leading to adverse health effects? 2) Does elevated folate status resulting from any form of folate intake affect vitamin B-12 function and its roles in sustaining health? 3) Does elevated folate intake, regardless of form, affect biological pathways leading to adverse health effects other than those linked to vitamin B-12 function? This article summarizes the proceedings of an August 2019 NIH expert workshop focused on addressing these research areas.

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Is folic acid safe for non–muscle-invasive bladder cancer patients? An evidence-based cohort study

American Journal of Clinical Nutrition ◽

10.1093/ajcn/nqx019 ◽

2018 ◽

Vol 107 (2) ◽

pp. 208-216 ◽

Cited By ~ 9

Author(s):

Huakang Tu ◽

Colin P Dinney ◽

Yuanqing Ye ◽

H Barton Grossman ◽

Seth P Lerner ◽

...

Keyword(s):

Bladder Cancer ◽

Folic Acid ◽

Folate Intake ◽

Invasive Bladder Cancer ◽

Folic Acid Intake ◽

Muscle Invasive Bladder Cancer ◽

Risk Of Recurrence ◽

Acid Intake ◽

Increased Risk ◽

Muscle Invasive

ABSTRACTBackgroundPatients with cancer are highly concerned about food choices and dietary supplements that may affect their treatment outcomes. Excess folic acid (synthetic folate) from supplements or fortification can lead to accumulation of unmetabolized folic acid in the systemic circulation and urine and may promote cancer growth, especially among those with neoplastic alterations.ObjectiveWe investigated the prospective association between synthetic compared with natural folate intake and clinical outcomes in non–muscle-invasive bladder cancer (NMIBC), which is a highly recurrent disease.DesignIn a cohort of 619 NMIBC patients, folate intake at diagnosis was assessed with a previously validated food-frequency questionnaire and categorized according to tertiles. After a median follow-up of 5.2 y, 303 tumor recurrence and 108 progression events were documented from medical record review. Multivariable Cox proportional hazards and logistic models were used to estimate adjusted HRs and ORs with 95% CIs.ResultsSynthetic folic acid intake was positively associated with a risk of recurrence among NMIBC patients (medium compared with low intake—HR: 1.72; 95% CI: 1.20, 2.48; P = 0.003; high compared with low intake—HR: 1.80; 95% CI: 1.14, 2.84; P = 0.01). Patients with a higher folic acid intake were more likely to have multifocal tumors at diagnosis (medium or high compared with low—OR: 2.08; 95% CI: 1.08, 4.02; P = 0.03). In contrast, natural folate intake tended to be inversely associated with the risk of progression (medium or high compared with low—HR: 0.68; 95% CI: 0.44, 1.04; P = 0.08).ConclusionsA high intake of synthetic folic acid, in contrast to the natural forms, is associated with an increased risk of recurrence in NMIBC and multifocal tumors at diagnosis, which suggests that folic acid may be unsafe for NMIBC patients. These findings provide some evidence for nutritional consultation with regard to folate intake among NMIBC patients.

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