Folic Acid 400 mcg by 21st Century — Ingredients, Evidence & Safety

🟢 80/100

This product is generally safe

Folate: 667mg is 667.0× the Tolerable Upper Intake Level (1.0mg)
50% of ingredients have research evidence

C Label Compliance Grade

Product Label

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Safety Alerts

⚠️ Folate: 667mg is 667.0× the Tolerable Upper Intake Level (1.0mg)

Label Data

1 Tablet(s) Serving Size

Single Vitamin and Mineral Product Type

50% Evidence Coverage

Supplement Facts — Evidence Check

Folate

667 mcg DFE (167% DV)

⚠️ Exceeds Tolerable Upper Intake Level by 667.0× (UL: 1.0 mg) 📚 225 studies (Tier A: 10, B: 105)

RDA 0.4mg This product: 667mg UL 1.0mg

Calcium

100 mg (8% DV)

Other Ingredients

Cellulose Maltodextrin Croscarmellose Sodium Stearic Acid Contains Less Than 2% of

Label Claims — Verification

❓ Nutrient

❓ All Other

❓ Structure/Function

All Other (99% of products) Structure/Function (77% of products) Nutrient (60% of products) Approved Health (5% of products)

Target Groups

Adult (18 - 50 Years) Gluten Free

Product Information

📋 Directions for Use

Directions: As a vitamin supplement, adults take one (1) tablet daily with any meal or as directed by a healthcare provider. Do not exceed recommended dosage.

⚠️ Warnings & Precautions

Do not exceed recommended dosage.

Warning: Consult a healthcare provider prior to use if pregnant, nursing, on medications, have a medical condition or are planning a medical procedure.

Stop use and contact a physician if adverse reactions occur. Folic Acid should not exceed 1,000 mcg per day.

Keep out of reach of children.

Do not use if product appears to be tampered with or seal is broken.

🧪 Formulation Notes

No added Sugar, Yeast, Preservatives, Artificial Flavors or Colors.

Gluten free

Folic Acid is an essential B vitamin that supports heart health.

Additional Information

Individual results may vary.

Store at room temperature.

Heart Health Support

Gluten free

Guaranteed quality Laboratory tested

Product Details

UPC / SKU 7 40985 21377 3

DSLD Entry Date 2019-08-23

Product Type Single Vitamin and Mineral

Form Tablet or Pill

Brand 21st Century

DSLD ID 205622

Data Updated 2026-04-11

Research Evidence

363 Research Sources

57 Avg Quality Score

187 Meta Analysis

56 Systematic Review

54 Rct

29 Guideline

26 Clinical Trial

6 Cochrane Review

2 Regulatory Source

1 Other

1 Openfda Safety

A Homocysteine-lowering interventions for preventing cardiovascular events

Meta Analysis The Cochrane database of systematic reviews 2017

PubMed DOI

A Community-based intervention packages for reducing maternal and neonatal morbidity and mortality and improving neonatal outcomes

Meta Analysis The Cochrane database of systematic reviews 2015

PubMed DOI

A Folate Intake and Risk of Pancreatic Cancer: A Systematic Review and Updated Meta-Analysis of Epidemiological Studies

Meta Analysis Digestive diseases and sciences 2021

PubMed DOI

A The Association Between the Risk of Hypertensive Disorders of Pregnancy and Folic Acid: A Systematic Review and Meta-Analysis

Meta Analysis Journal of pharmacy & pharmaceutical sciences : a publication of the Canadian Society for Pharmaceutical Sciences, Societe canadienne des sciences pharmaceutiques 2021

PubMed DOI

A A Comparative Study Evaluating the Effectiveness of Folate-Based B Vitamin Intervention on Cognitive Function of Older Adults under Mandatory Folic Acid Fortification Policy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Meta Analysis Nutrients 2024

PubMed DOI

A Associations between serum Homocysteine, vitamin B9, and vitamin B12 levels and the formation of intracranial Aneurysms: A systematic review and meta-analysis

Meta Analysis Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia 2025

PubMed DOI

A Intake of vitamin B6, folate, and vitamin B12 and risk of coronary heart disease: a systematic review and dose-response meta-analysis of prospective cohort studies

Meta Analysis Critical reviews in food science and nutrition 2019

PubMed DOI

A Beneficial effects of folic acid supplementation on lipid markers in adults: A GRADE-assessed systematic review and dose-response meta-analysis of data from 21,787 participants in 34 randomized controlled trials

Meta Analysis Critical reviews in food science and nutrition 2022

PubMed DOI

A Folic acid supplementation and blood pressure: a GRADE-assessed systematic review and dose-response meta-analysis of 41,633 participants

Meta Analysis Critical reviews in food science and nutrition 2023

PubMed DOI

A Digital tracking, provider decision support systems, and targeted client communication via mobile devices to improve primary health care

Meta Analysis The Cochrane database of systematic reviews 2025

PubMed DOI

View all evidence for Folate →