Dietary sources of riboflavin

FMN. The main dietary sources of riboflavin are milk and dairy products. In addition, because of its intense yellow color, riboflavin is widely used as a food additive. 

The route of exposure is oral. Dietary sources of riboflavin include broccoli, spinach, asparagus, enriched flour, yeast, eggs, milk, cheese, mackerel, trout, poultry, liver, and kidneys. 

The main dietary sources of riboflavin are milk and dairy products, which provide 25% or more of the total intake in most diets, and it is noteworthy that average riboflavin status in different countries reflects milk consumption to a considerable extent. In addition, because of its intense yellow colour, riboflavin is widely used as a food colour. 

Measurements of the plasma pool of riboflavin following test doses is not a viable method of measuring absorption, because redistribution to other tissue sites plus urinary excretion takes place too rapidly for this pool to be representative of the amoimt absorbed. Although the urinary response to a test dose has been the most commonly used approach to studies of intestinal absorption in humans, it suffers from the potential disadvantage that physiological intakes, and especially low intakes of riboflavin from poor food sources, cannot be measured by this technique. Such studies of small doses are however needed, in order to determine the factors that modulate riboflavin absorption in developing countries, where dietary sources of riboflavin are minimal and clinical signs of riboflavin... 

Q-32 What is dietary requirement of Riboflavin (Vitamin B-2) and what are dietary sources of it ... 

Uses Catalyst in tan-accelerating formulations direct food additive nutrient, dietary supplement, source of riboflavin in foods, milk prods., infant formulas, and pharmaceuticals colorant in foods enzyme cofactor vitamin biological additive in cosmetics Regulatory FDA 21CFR 184.1697, GRAS Europe listed UK, Japan approved BP, EP compliance... 

Riboflavin (vitamin B2) also acts as a cofactor and is a precursor for the coenzymes flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD). These coenzymes are used in metabolism and catalyze numerous oxidation—reduction reactions. Among the good dietary sources for riboflavin, most animal-derived products, milk and dairy products, are pointed out. Foods are usually pretreated before analysis of riboflavin following similar procedures to those described for vitamin Bi. Similarly, fluorescence detection is mostly employed (370 nm ex., 520 ran em.) after RP separation. 

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. 

Also called riboflavin, is one of the most widely distributed vitamins. All plants and animal cells contain it, but there are very few rich sources. Yeast and liver have the highest concentrations, but the commonest dietary sources are milk and milk products, meat, eggs and leafy green vegetables. Cereal grains, although poor sources of riboflavin are important for those who rely on cereals as their main dietary component. Animal sources of riboflavin are better absorbed than vegetable sources. 

The conversion of riboflavin to flavin mononucleotide (FMN) is catalyzed by flavokinase (Figure 9.73). This conversion may occur during absorption through the gut mucosa or in other organs. The subsequent conversion of FMN to flavin adenine dinucleotide (FAD) is catalyzed by FAD synthase. FAD synthase uses ATP as a source of an adenylyl group, in this conversion (McCormick et ah, 1997). Various phosphatases, including those of the gut mucosa, can catalyze the breakdown of FAD to FMN and of FMN to free riboflavin. Dietary flavins that are covalently botmd to proteins are thought to be unavailable and not to contribute to our dietary needs (Bates et ah, 1997). 

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. 

Whereas plants, fiingi, and certain microorganisms obtain riboflavin by biosynthesis, higher animals depend on dietary sources. The biosynthesis of riboflavin has been reviewed repeatedly [288-294]. 

In the food industry, vitamins are used to enrich many products, by the processes of restitution and fortification (enrichment). Restitution means the return of the vitamin content to the original level found in the raw material fortification is enrichment to a higher level needed for physiological or other reasons. Some vitamins have also found use as natural dyes (riboflavin and provitamins A, in particular -carotene) and as antioxidants (provitamins A, vitamin E and vitamin C). Intake of vitamins currently significantly influences the consumption of various concentrated sources of vitamins such as dietary supplements and multivitamin preparations. Intake of vitamins in these concentrated forms may lead, in extreme cases, to hypervitaminosis. 

When considering sources of niacin, it should be noted that niacin can be, and is, synthesized by the intestinal flora. However, the amount produced is only of minor importance in the human. By contrast, as with thiamin and riboflavin, ruminants (cattle, sheep, etc.) have no dietary requirements for niacin because of bacterial synthesis in the rumen. 

Milk is not a rich source of dietary folate compared to other foods however, as is the case for riboflavin, folate concentrations can be significantly increased in many dairy products due to microbial fermentation. Among dairy products, fermented milks are considered a good potential matrix for folate fortification because folate-binding proteins present in milk improve folate stability and enhance the bioavailability of both 5-methyltetrahydrofolate (the most predominant natural form of the vitamin) and folic acid (Jones and Nixon 2002 Aryana 2003 Verwei et al. 2003). However, due to the potential risks of fortification with folic acid, the elaboration of fermented milks containing elevated levels of natural folates would be a better suited alternative. 

See also Antioxidants Observational Studies Intervention Studies. Ascorbic Acid Physiology, Dietary Sources and Requirements. Carotenoids Chemistry, Sources and Physiology Epidemiology of Health Effects. Copper. Folic Acid. Riboflavin. Selenium. Vitamin E Physiology and Health Effects. Zinc Physiology. 

In foods vitamin B2 occurs free or combined both as FAD and FMN and complexed with proteins. Riboflavin is widely distributed in foodstnffs, but there are very few rich sources. Only yeast and liver contain more than 2mg/100g. Other good sources are milk, the white of eggs, fish roe, kidney, and leafy vegetables. Since riboflavin is continuously excreted in the urine, deficiency is qnite common when dietary intake is insufficient. The symptoms of deficiency are cracked and red lips, inflammation of the lining of the month and tongue, mouth ulcers, cracks at the comer of the mouth, and sore throat. Overdose of oral intake present low toxicity, probably explained by the limited capacity of the intestinal absorption mechanism [417]. 

The many diverse components of milk have demonstrable effects on human health. Perhaps, the most commonly associated component of dairy food is that of dietary calcium. Dairy products provide the most significant contribution to dietary calcium intake in the modem Western diet. It has been estimated that dairy products contribute to >72% of dietary calcium in the United States (Huth et al., 2006). Calcium is an important mineral for maintenance of optimal bone health (Bonjour et al., 2009) and is an integral component of key metabolic pathways relating to, for example, muscle contraction both in skeletal and smooth muscle (Cheng and Lederer, 2008). Further, dairy products contribute other essential nutrients in the diet, such as proteins, phosphorus, potassium, zinc, magnesium, selenium, folate, riboflavin, vitamin B12, and vitamin A (Haug et al., 2007 Huth et al., 2006). Low-fat milk alternatives are fortified with vitamin A and vitamin D which is added to milk and fermented milk in many countries making it an important source for vitamin D (Huth et al., 2006). 

Sources Dietary Reference Intakes for Calcium, Phosphorous, Magnesium, Vitamin D, and Huoride (1997) Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin 85, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline (1998) EHetary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids (2000) Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc (2001) Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate (2005) and EHetary Reference Intakes for Calcium and Vitamin D (2011). These reports may be accessed via www.nap.edu A Tolerable Upper Intake Level (UL) is the highest level of daily nutrient intake that is likely to pose no risk of adverse health effects to almost all individuals in the general population. Unless otherwise specified, the UL represents total intake from food, water, and supplements. Due to a lack of suitable data, ULs could not be established for vitamin K, thiamin, riboflavin, vitamin B12, pantothenic acid, biotin, and carotenoids. In the absence of a UL, extra caution may be warranted in consuming levels above recommended intakes. Members of the general population should be advised not to routinely exceed the UL. The UL is not meant to ply to individuals who are treated with the nutrient under medical supervision or to individuals with predisposing conditions that modify their sensitivity to the nutrient... 

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... 

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. 

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