Guidelines on Vitamins

The Food and Nutrition Board, which is a subgroup of the Institute of Medicine, developed guidelines for various vitamins based on age and sex. Guidelines for vitamins are given as Dietary Reference Intakes, or DRIs, which are defined as the amount of the vitamin needed to maintain good health and prevent chronic diseases. Some vitamins also have Tolerable Upper Intake Levels, or ULs, which is the highest amount of the vitamin that can be consumed in a single day without causing harm to the body.

Vitamin A

The DRI for vitamin A is set at 700 micrograms per day for women and 900 micrograms per day for men. Vitamin A can be toxic in high amounts, so the UL is set at 3,000 micrograms per day for both adult men and women.

Vitamin D

Adult women and men between the ages of 19 and 50 should aim to consume 5 micrograms of vitamin D every day. Adults between the ages of 51 and 70 should consume 10 micrograms per day, and adults over 70 should aim for 15 micrograms per day. The UL for vitamin D is 50 micrograms per day for all ages and sexes.

Vitamin E

All adults should aim to consume 15mg of vitamin E every day. Women who are lactating should consume 19mg of vitamin E per day. The UL is set at 1,000mg per day.

Vitamin K

Adult females should consume 90 micrograms of vitamin K per day, and adult males should consume 120 micrograms per day. Excess consumption of vitamin K has not been shown to cause any adverse side effects, so it does not have a UL.

Vitamin C

The recommended dietary intake for vitamin C is 90mg per day for men and 75mg per day for women. The UL has been set at 2,000mg per day for both adult men and women.

B Vitamins

Eight vitamins make up the water-soluble B vitamins group. These vitamins include thiamin, riboflavin, niacin, vitamin B6, folate, vitamin B12, pantothenic acid and biotin. The recommended dietary intake for thiamin is 1.1mg for women and 1.2mg for men. Riboflavin has a recommended intake of 1.1mg for women and 1.3mg for men. Women require 14mg of niacin per day whereas men require 16mg every day. The UL for niacin is set at 35mg per day.

Recommended intakes for vitamin B6 are given in ranges. Women require 1.3 to 1.5mg per day and men require 1.3 to 1.7mg per day. The recommended dietary intake for folate is 400 micrograms per day for both men and women. The UL is set at 1,000 micrograms per day for both groups as well. All adults require 2.4 micrograms of B12, 5mg of pantothenic acid and 30 micrograms of biotin daily. None of these B vitamins have a UL.