Niacin vitamin dietary sources

Other Additives. Cats cannot convert tryptophan to niacin (22), or carotene to vitamin A in sufficient amounts to meet thein needs (23). These deviations, as compared with other animals, need not produce problems because added dietary sources of niacin and vitamin A provide the needs of cats. 

Good dietary sources of this vitamin are liver, kidney, lean meat, chicken, fish, wheat, barley, rye, green peas, yeast, peanuts, and leafy vegetables. In animal tissues, the predominant form of niacin is the amide. Niacin content of some foods are listed in Table 9-22. 

Niacin is present in tissues, and therefore in foods, iargeiy as the nicotinamide nucleotides. The postmortem hydrolysis of NAD(P) is extremely rapid in animal tissues, and it is likely that much of the niacin of meat (a major dietary source of the vitamin) is free nicotinamide. 

NAD% the oxidized form of NADH, is a biological oxidizing agent capable of oxidizing alcohols to carbonyl compounds (it forms NADH in the process). NAD is synthesized from the vitamin niacin, which can be obtained from soybeans among other dietary sources. Breakfast cereals are fortified with niacin to help people consume their recommended daily allowance of this B vitamin. 

Niacin (nicotinic acid and nicotinamide) is also known as vitamin B3. Both nicotinic acid and nicotinamide can serve as the dietary source of vitamin B3. 

Tree nuts can be good dietary sources (>10% of recommended dietary allowances [RDA] or adequate intake [Al]) of most vitamins except vitamins A and cobalamin (B,2). At suggested consumption level (1.5 ounces or 42.5g/day), acorn and pine nuts are excellent sources of folate and vitamin K (Table 2.7). In case of thiamin (Bj), niacin (B3), and pyridoxine (Bg), tree nuts offer alternative sources of these vitamins when more abundant animal sources are not available or are not consumed. 

Sources Dietary Reference Intakes for Calcium, Phosphorous, Magnesium, Vitamin D, and Fluoride (1997) Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin Folate, Vitamin B, Pantothenic Acid, Biotin, and Choline (1998) Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids (2000) Dietary Reference hitakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc (2001) Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (2002/2005) and Dietary Reference Intakes for Calcium and Vitamin D (2011). These reports may be accessed via www.nap.edu... 

Sources Dietary Reference Intakes for Calcium, Phosphorous, Magnesium, Vitamin D, and Fluoride (1997) Dietary Reference Intakes for Thieunin, Riboflavin, Niacin, Vitamin Be,... 

Synthesis of NAD and NADP Is compromised in vitamin Bg deficient, see dietary sources fi>r niacin (Chapter 53)... 

Trigonellln 1-methylnicotinic acid, a metabolite of nicotinic acid or nicotinamide found in many plants. It is both a hormone and a storage form of nicotinic acid. It is apparently not a niacin metabolite in animals, although it is found in the urine of coffee drinkers. Green coffee beans contain relatively large (> 500 mg/kg) amounts of X roasting the beans converts T. to nicotinic acid. Coffee is a significant dietary source of niacin (see Vitamins) in South and Central America. 

The main dietary sources of nicotinamide are meat, fish, and egg yolks. During World War II, when the restrictions mainly involved these substances, the primary sources of vitamin PP were bread, tomatoes, spinach, and fruit. Some cereals—rice, wheat, bran, and corn—have a low biological activity with respect to niacin activity because these cereals contain niacin in the form of niacinogen. The vitamin is not freed by the gastric or intestinal juices and is therefore not... 

In the organism that Is required In small amounts In food to sustain the normal metabolic functions of life. The key to this definition Is that this chemical compound must be supplied to the organism because the animal cannot synthesize vitamins. Lack of It produces a specific deficiency syndrome and supplying It cures that deficiency. An exception to this definition Is vitamin D, which can be made In the skin upon adequate exposure to sunlight. However, without adequate exposure, the animal Is dependent on a dietary source. Biotin, panthothenlc acid, and vitamin R are made by bacteria In the human Intestine, based on a symbiotic relation-ship and, thus, are not required by the human. Niacin can also be synthesized In humans from the amino acid tryptophane. 

Sources Standing Committee on the Scientific Evaluation of Dietary Reference Intakes, Food and Nutrition Board, Institute of Medicine Dietary Reference Intakes for calcium, phosphorus, magnesium, vitamin D and fluoride, 1997 Dietary reference intakes for thiamin, riboflavin, niacin, vitamin B, folate, vitamin Bj, pantothenic acid, biotin and choline, 1998 Dietary reference intakes for vitamin C, vitamin E, selenium and carotenoids, 2000 Dietary Reference Intakes for vitamin A, vitamin K, arsenc, boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, silicon, vanadium and zinc, 2001, National Academy Press Washington, DC. 

They are the major dietary source of vitamin B-12 and vitamin B-6, and they supply appreciable amounts of vitamin A, biotin, niacin, pantothenic acid, riboflavin, and thiamin. 

PORK AS A FOOD. Pork is an important food and a rich source of many essential nutrients. An average 3.5 oz (99.4 g) serving of cooked pork ham provides 37 g of protein (that s 2/ 3 of the recommended daily allowance of protein) and 8.8 g of fat, along with being an excellent source of minerals and vitamins. Its high-quality protein contains all the essential amino acids needed to build, maintain, and repair body tissues. Pork is rich in iron, and the iron is readily used in the formation and maintenance of red blood cells. Also, pork is a major dietary source of the B vitamins, especially thiamin, riboflavin, and niacin. Also pork is about 98% digestible. 

Red raspberries are one of the plant worlds richest sources of vitamins C and K, the essential mineral manganese, and dietary fiber. Contents of vitamin A (from seed carotenoids), B vitamins 1 through 3 (thiamin, riboflavin, niacin, respectively), iron, calcium, and potassium are also at good levels. 

L-Tryptophan is one of the essential amino acids in animals. In addition, it is the biosynthetic precursor to other important molecules such as serotonin (thus, melatonin) and niacin. Until 1989, L-Tryptophan was sold singly over-the-counter and as a constituent in dietary supplement combinations. One of several effects that ingesting L-tryptophan has on the body is an increase in serotonin levels. Partly because of this, L-tryptophan supplements commonly were used to treat premenstrual syndrome, as a sleep aid and as a natural antidepressant [8] (http //www. webmd.com/vitamins-supplements/ingredientmono-326-L-TRYPTOPHAN.aspx activebigredientId=326 activeIngredientName=L-TRYPTOPHAN source=3). 

It is principally known for its high vitamin C content, being one of the most important natural sources for this vitamin (Muller et al. 2010 Vendramini and Trugo 2000). The consumption of three fruit units per day satisfies the vitamin C recommended dietary allowance for an adult. In addition, it presents amounts of thiamine, riboflavin, niacin, proteins, and mineral salts, mainly iron, calcium, and phosphorous (Mezquita and Vigoa 2000). Mezadri et al. (2008) observed that contents in total... 

As can be seen from Table 1, different types of foods differ considerably, not only in their total contribution to nicotinic acid equivalents, but also in the ratio of the contribution from preformed niacin and from tryptophan. In a typical Western diet, it has been calculated that if the 60 mg tryptophan = 1 mg niacin formula is applied, then preformed niacin provides about 50% of the niacin supply in the diet. In practice it seems possible for all of the niacin requirement to be provided by dietary tryptophan in Western diets. As is the case for the other B vitamins, meat, poultry, and fish are excellent sources of niacin equivalents, followed by dairy and grain products, but as noted above, certain grains such as maize, and whole highly polished rice, can be very poor sources and may be associated with clinical deficiency if the diets are otherwise poor and monotonous. 

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