The U.S. RDA for niacin is the amount of the vitamin used as a standard in nutrition labeling of foods. This allowance is based on the 1968 Recommended Dietary Allowances (RDA) for 24 sex-age categories set by the Food and Nutrition Board of the National Academy of Sciences. The 1989 RDA has been set at 15 milligrams per day for women 19 to 50 years of age and 19 milligrams for men 19 to 50 years of age.
In 1985 and 1986, 44 percent of the niacin in the diets of women came from meat, poultry, and fish. Grain products such as breads and cereals supplied about 31 percent of the niacin consumed. Foods that contain small amounts of niacin but are not considered good sources can contribute significant amounts of niacin to an individual's diet if these foods are eaten often or in large amounts.
WHY DO WE NEED NIACIN?Niacin, a water-soluble vitamin, helps the body release energy from protein, fat, and carbohydrate during metabolism. Niacin assists in the functioning of the digestive system, skin, and nerves.
DO WE GET ENOUGH NIACIN?
According to USDA surveys, the intake of niacin by American women and men 19 to 50 years of age averaged above the RDA.
Niacin is a type of B vitamin. It is water-soluble, which means it is not stored in the body. Water-soluble vitamins dissolve in water. Leftover amounts of the vitamin leave the body through the urine. That means you need a continuous supply of such vitamins in your diet.
Niacin can be formed in the body from tryptophan, an essential amino acid found in meat, poultry, fish, and eggs. Therefore, if your diet contains these foods, your need for niacin from other sources will be reduced.
RECOMMENDATIONSRecommended daily allowances (RDAs) are defined as the levels of intake of essential nutrients that the Food and Nutrition Board at the Institute of Medicine has found to be adequate to meet the known nutrient needs of most healthy persons.
The Food and Nutrition Board at the Institute of Medicine recommends the following dietary intake for niacin:
Adolescents and Adults
Specific recommendations depend on age, gender, and other factors (such as pregnancy). Women who are pregnant or producing breast milk (lactating) need higher amounts. Ask your health care provider which amount is best for you.
HOW CAN WE GET ENOUGH NIACIN?Eating a variety of foods that contain niacin is the best way to get an adequate amount. Healthy individuals who eat a balanced diet rarely need supplements. The list of foods will help you select those that are good sources of niacin as you follow the Dietary Guidelines. The list of good sources was derived from the same nutritive value of foods tables used to analyze information for recent food consumption surveys of the U.S. Department of Agriculture, Human Nutrition Information Service.
Niacin (also known as vitamin B3) is found in dairy products, poultry, fish, lean meats, nuts, and eggs. Legumes and enriched breads and cereals also supply some niacin.
HOW TO PREPARE FOODS TO RETAIN NIACINNiacin is fairly stable, but some niacin can be lost during cooking as it dissolves in the cooking liquid. Losses in preparation and storage are slight. To retain niacin:
WHAT ABOUT ENRICHED OR FORTIFIED FOODS?Pasta and most breads made from refined flours are enriched with niacin because niacin is one of the nutrients lost in processing. Other nutrients added to refined flours and pasta are iron, thiamin, and riboflavin. Enriched products or products made from enriched flour are labeled as such.
Most ready-to-eat and instant-prepared cereals are fortified with niacin. Fortified ready-to-eat cereals usually contain at least 25 percent of the U.S. RDA for niacin. Since cereals vary, check the label on the package for the percentage of the U.S. RDA for a specific cereal.
WHAT IS A SERVING?
The serving sizes used on the list of good sources are only estimates of the amounts of food you might eat. The amount of nutrient in a serving depends on the weight of the serving. For example, 3 ounces of cooked lean pork loin roast contains more niacin than a cooked pork chop, because the chop has less than 3 ounces of lean meat. Therefore, a serving of the pork loin roast has 25 percent of the U.S. RDA while the pork chop has less than 20 percent.
WHAT ARE GOOD SOURCES OF NIACIN?
FOOD SELECTED PERCENTAGE OF SERVING SIZE U.S. RDA (1)(1) A selected serving size contains -
+ 10-24 percent of the U.S. RDA for adults and children over 4 years of age
(2) Breads and cereals listed are enriched unless otherwise noted. See section on enriched or fortified foods.