VITAMIN

RDI*

1968 RDA**

1974 RDA**

1980 RDA**

1989 RDA**

DRIs***

Vitamin A

5000 IU

5000 IU

1000 RE
(5000 IU)

1000 RE

1000 RE

900 mcg
(3000 IU)

Vitamin C

60 mg

60 mg

45 mg

60 mg

60 mg

90 mg

Vitamin D

400 IU
(10 mcg)

400 IU
(10 mcg)

400 IU
(10 mcg)

10 mcg
(400 IU)

10 mcg
(400 IU)

15 mcg
(600 IU)

Vitamin E

30 IU
(20 mg)

30 IU
(20 mg)

15 IU
(10 mg)

10 mg
(15 IU)

10 mg
(15 IU)

15 mg #

Vitamin K

80 mcg

--

--

70-140 mcg

80 mcg

120 mcg

Thiamin

1.5 mg

1.5 mg

1.5 mg

1.5 mg

1.5 mg

1.2 mg

Riboflavin

1.7 mg

1.7 mg

1.8 mg

1.7 mg

1.8 mg

1.3 mg

Niacin

20 mg

20 mg

20 mg

19 mg

20 mg

16 mg

Vitamin B-6

2 mg

2 mg

2 mg

2.2 mg

2 mg

1.7 mg

Folate

0.4 mg
(400 mcg)

400 mcg

400 mcg

400 mcg

200 mcg

400 mcg food,
200 mcg
synthetic ##

Vitamin B-12

6 mcg

6 mcg

3 mcg

3 mcg

2 mcg

2.4 mcg ###

Biotin

(300 mcg)

150-300 mcg

100-300 mcg

100-200 mcg

30-100 mcg

30 mcg

Pantothenic

10 mg

5-10 mg

5-10 mg

4-7 mg

4-7 mg

5 mg

Choline

--

--

--

--

--

550 mg

* The Reference Daily Intake (RDI) is the value established by the Food and Drug Administration (FDA) for use in nutrition labeling. It was based initially on the highest 1968 Recommended Dietary Allowance (RDA) for each nutrient, to assure that needs were met for all age groups.

** The RDAs were established and periodically revised by the Food and Nutrition Board. Value shown is the highest RDA for each nutrient, in the year indicated for each revision.

*** The Dietary Reference Intakes (DRI) are the most recent set of dietary recommendations established by the Food and Nutrition Board of the Institute of Medicine, 1997-2001. They replace previous RDAs, and may be the basis for eventually updating the RDIs. The value shown here is the highest DRI for each nutrient.

# Historical vitamin E conversion factors were amended in the DRI report, so that 15 mg is defined as the equivalent of 22 IU of natural vitamin E or 33 IU of synthetic vitamin E.

## It is recommended that women of childbearing age obtain 400 mcg of synthetic folic cid from fortified breakfast cereals or dietary supplements, in addition to dietary folate.

### It is recommended that people over 50 meet the B-12 recommendation through fortified foods or supplements, to improve bioavailability.