Niacin 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. 

The RDA for niacin is expressed in terms of energy intake 6.6 mg niacin equivalent (NE, 1 mg niacin or 60 mg tryptophan) per 1000 kcal (4186 kJ) per day is recommended (13NEday-1 minimum). This is approximately equivalent to 19 and 15 mg NE day -1 for men and women, respectively. The UK RNI value for niacin is 6.6 mg NE per 1000 kcal (4186 kJ) per day for adults. The richest dietary sources of niacin are meat, poultry, fish and whole-grain cereals. 

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. 

Cats, which have some 30- to 50-fold higher activity of picolinate carboxylase than other species, are entirely reliant on a dietary source of preformed niacin, and are not capable of any significant synthesis of NAD from tryptophan. 

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. 

Q-35 What is dietary requirement of Niacin and what are dietary sources of it ... 

Routes of exposure are oral and intravenous. It can also be given intramuscularly or subcutaneously but intravenous administration is recommended when possible. Dietary sources of niacin are green vegetables, eggs, milk, and other dairy products, legumes, yeast, whole grains, lean meats, liver, and fish. 

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. 

Synonyms Nicotinic acid aluminum salt 3-Pyridinecarboxylic acid aluminum salt Tris (nicotinato) aluminum Empirical C18H12AIN3O6 Properties Solid m.w. 393.30 Hazardous Decomp. Prods. Heated to decomp., emits toxic fumes of NOx Uses Nutrient, dietary supplement, niacin source in foods for special dietary use Regulatory FDA 21CFR 172.310 Aluminum nitrate... 

Davis, R. G., 1978, Increased bitter taste detection thresholds in Yucatan inhabitants related to coffee as a dietary source of niacin, Chem. Senses Flav., 3 423. 

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. 

Average intakes of tryptophan in Western diets will more than meet requirements without the need for a dietary source of preformed niacin. 

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. 

The RDA for niacin is based on the concept that niacin coen2ymes participate in respiratory en2yme function and 6.6 niacin equivalents (NE) are needed per intake of 239 kj (1000 kcal). One NE is equivalent to 1 mg of niacin. Signs of niacin deficiency have been observed when less than 4.9 NE/239 kj or less than 8.8 NE per day were consumed. Dietary tryptophan is a rich source of niacin and the average diet in the United States contains 500—1000 mg of tryptophan. In addition, the average diet contains approximately 8—17 mg of niacin. In total, these two quantities total 16—34 NE daily. Table 5 Hsts the RDA and U.S. RDA for niacin (69). 

A 70-B. Although dietary niacin is the major source of the nicotinamide ring of NAD, it may also be produced from tryptophan. 

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. 

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