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TABLE 3-9  continued
Vitamin	Alternative Names	1980 RDA, amount per day a	Major Food Sources	Food Supply, Intakes, and Nutritional Status
Niacin (only preformed niacin—not that formed in the metabolism of tryptophan— is reported in national surveys.)	Nicotinic acid Nicotinamide	Generally 6.6 mg NEh/1,00 kcal Infants, 6-8 mg NE Children, 1-10 years, 9-16 mg NE, Males 11->51 years, 16-19 mg NE Females 11->51 years, 13-15 mg NE Pregnant women, +2 mg NE Lactating women,+5 mg NE	Preformed niacin: meats, poultry, fish; whole and enriched grain products; legumes; nuts. In addition, some of the tryptophan present in meats, poultry, fish, cheese, legumes, and seeds can be converted in the body to niacin. The highest proportion of performed niacin intakes in the 1977-1978 NFCS came from meat, poultry, and fish (44%) and grain products (30%).	Availability of preformed niacin in the food supply has increased since 1909-1913, partly because of the enrichment of flour and cereal products In the 1985 CSFII, mean intake of preformed niacin per 1,000 kcal was 10.8 mg NE for men 19 to 50 years old and 9.6 mg NE for children 1 to 5 years old.d In the 1977-1978 NFCS, the mean intake for all age and sex groups was 124% of the RDA. For the same age groups, intake levels were higher for males than for females. Intake levels were lowest for those 9 to 18 years of age and highest for those ages 19 to 64 years. Those below poverty level had lower intakes than those of higher income groups.e JNMEC concluded that the dietary intakes of the U.S. population appear to be adequate in niacin but that public health monitoring should continue. Health indicators of nutritional status have not been obtained in national surveysf
Vitamin B6 (food composition data for B6 are less reliable than is desirable.)	Pyridoxine Pyridoxal Pyridoxamine	Generally 0.02 mg/g of protein consumed. The RDA for vitamin B6 assumes that the usual daily protein intake for women is 100 g and for men 110 g. Infants, 0.3-0.6 mg Children 1-10 years, 0.9-1.6 mg Males 11->51 years, 1.8-2.2 mg Females 11-> 51 years, 1.8-2.0 mg Pregnant women, 2.0 mg +0.6 mg Lactating women, 2.0 mg +0.5 mg	Meat, poultry, fish; bananas; and nuts. The highest proportion of vitamin B6 intakes in the 1977-1978 NFCS came from meat, poultry, and fish (40%); fruits and vegetables (23%); and grain products (19%).	Availability of vitamin B6 in the food supply appears to have decreased from 1909-1913 to 1967-1968, but increased by 8% in the past two decades (Table 3-3). In the 1985 CSFII, mean intakes of women 19 to 50 years old were 57% of the RDA, whereas mean intakes for men 19 to 50 years old were 85% of the RDA. For children 1 to 5 years old, mean intakes were 119% of the RDA. Intakes were somewhat higher among higher income groups. The mean intake in terms of mg B6/g protein for women was 0.019 and for children, 0.023.d In the 1977-1978 NFCS, the mean intake of all people was 75% of the RDA, but females over 14 years old were between 58 and 63% of the RDA. The percentage of the population having at least the B6-to-protein ratio was about 33% higher than the percentage of the population having at least the RDA.e JNMEC concluded that both the B6 intake and the status of the population require further investigation. Health indicators of vitamin B6 status have not been assessed in national surveys.f