National Academies Press: OpenBook
« Previous: B Acknowledgments
Suggested Citation:"C Système International d'Unités." Institute of Medicine. 1998. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, DC: The National Academies Press. doi: 10.17226/6015.
×

C
Système International d’Unités

In the text of this report, the Système International d’Unités (SI units) are presented for hematological and clinical chemistry values, with traditional units in parentheses. The conversion factors for hematological and clinical chemistry values are given in Table C-1.

Suggested Citation:"C Système International d'Unités." Institute of Medicine. 1998. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, DC: The National Academies Press. doi: 10.17226/6015.
×

TABLE C-1 Factors Used to Convert Between Traditional Units and the Système International d’Unités (SI Units)

Nutrient

Traditional Unit

Conversion Factor

SI Unit

Molecular Weight

Thiamin

µg/24h

0.003324468

µmol/d

300.8

Thiamin hydrochloride

µg/24h

0.00296472

µmol/d

337.3

Riboflavin

µg/dL

26.5674814

nmol/L

376.4

Flavin mononucleotide (FMN)

ng/mL

2.191540653

nmol/L

456.3

Flavin-adenine dinucleotide (FAD)

ng/mL

1.205545509

nmol/L

829.5

Niacin

mg/d

8.123476848

µmol/d

123.1

Niacinamide

mg/d

8.19000819

µmol/d

122.1

Pyridoxine hydrochloride

mg

4.86381323

µmol

205.6

Vitamin B6

ng/mL

5.910165485

nmol/L

169.2

Pyridoxal

ng/mL

5.980861244

nmol/L

167.2

Pyridoxamine

ng/mL

5.94530321

nmol/L

168.2

Pyridoxal 5′-phosphate

ng/mL

4.046944557

nmol/L

247.1

Folic acida

ng/mL

2.265518804

nmol/L

441.4

5-Methyltetrahydrofolateb

ng/mL

2.176752286

nmol/L

459.4

Vitamin B12 (cyano)

pg/mL

0.737789582

pmol/L

1,355.4

Coenzyme B12

pg/mL

0.633071664

pmol/L

1,579.6

Methylcobalamin

pg/mL

0.743826242

pmol/L

1,344.4

Pantothenic acid

µg/mL

4.562043796

µmol/L

219.2

Coenzyme A

µg/mL

1.302931596

µmol/L

767.5

Biotin

ng/mL

4.093327876

nmol/L

244.3

Choline base

mg/mL

8.250825083

mmol/L

121.2

Choline chloride

mg/mL

7.163323782

mmol/L

139.6

NOTE: Conversion factors convert traditional values to SI units. To convert to SI units, multiply the traditional unit by the conversion factor. To convert to traditional units, divide the SI unit by the conversion factor.

a Pteroylglutamic acid.

b Most predominant form in serum, plasma, and erythrocytes.

Suggested Citation:"C Système International d'Unités." Institute of Medicine. 1998. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, DC: The National Academies Press. doi: 10.17226/6015.
×
Page 451
Suggested Citation:"C Système International d'Unités." Institute of Medicine. 1998. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, DC: The National Academies Press. doi: 10.17226/6015.
×
Page 452
Next: D Search Strategies »
Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline Get This Book
×

Since 1941, Recommended Dietary Allowances (RDAs) has been recognized as the most authoritative source of information on nutrient levels for healthy people. Since publication of the 10th edition in 1989, there has been rising awareness of the impact of nutrition on chronic disease. In light of new research findings and a growing public focus on nutrition and health, the expert panel responsible for formulation RDAs reviewed and expanded its approach--the result: Dietary Reference Intakes.

This new series of references greatly extends the scope and application of previous nutrient guidelines. For each nutrient the book presents what is known about how the nutrient functions in the human body, what the best method is to determine its requirements, which factors (caffeine or exercise, for example) may affect how it works, and how the nutrient may be related to chronic disease.

This volume of the series presents information about thiamin, riboflavin, niacin, vitamin B6, folate, vitamin B12, pantothenic acid, biotin, and choline.

Based on analysis of nutrient metabolism in humans and data on intakes in the U.S. population, the committee recommends intakes for each age group--from the first days of life through childhood, sexual maturity, midlife, and the later years. Recommendations for pregnancy and lactation also are made, and the book identifies when intake of a nutrient may be too much. Representing a new paradigm for the nutrition community, Dietary Reference Intakes encompasses:

  • Estimated Average Requirements (EARs). These are used to set Recommended Dietary Allowances.
  • Recommended Dietary Allowances (RDAs). Intakes that meet the RDA are likely to meet the nutrient requirement of nearly all individuals in a life-stage and gender group.
  • Adequate Intakes (AIs). These are used instead of RDAs when an EAR cannot be calculated. Both the RDA and the AI may be used as goals for individual intake.
  • Tolerable Upper Intake Levels (ULs). Intakes below the UL are unlikely to pose risks of adverse health effects in healthy people.

This new framework encompasses both essential nutrients and other food components thought to pay a role in health, such as dietary fiber. It incorporates functional endpoints and examines the relationship between dose and response in determining adequacy and the hazards of excess intake for each nutrient.

  1. ×

    Welcome to OpenBook!

    You're looking at OpenBook, NAP.edu's online reading room since 1999. Based on feedback from you, our users, we've made some improvements that make it easier than ever to read thousands of publications on our website.

    Do you want to take a quick tour of the OpenBook's features?

    No Thanks Take a Tour »
  2. ×

    Show this book's table of contents, where you can jump to any chapter by name.

    « Back Next »
  3. ×

    ...or use these buttons to go back to the previous chapter or skip to the next one.

    « Back Next »
  4. ×

    Jump up to the previous page or down to the next one. Also, you can type in a page number and press Enter to go directly to that page in the book.

    « Back Next »
  5. ×

    Switch between the Original Pages, where you can read the report as it appeared in print, and Text Pages for the web version, where you can highlight and search the text.

    « Back Next »
  6. ×

    To search the entire text of this book, type in your search term here and press Enter.

    « Back Next »
  7. ×

    Share a link to this book page on your preferred social network or via email.

    « Back Next »
  8. ×

    View our suggested citation for this chapter.

    « Back Next »
  9. ×

    Ready to take your reading offline? Click here to buy this book in print or download it as a free PDF, if available.

    « Back Next »
Stay Connected!