riboflavin deficiency

Riboflavin Deficiency

Definition

Riboflavin deficiency occurs when the chronic failure to eat sufficient amounts of foods that contain riboflavin produces lesions of the skin, lesions of smooth surfaces in the digestive tract, or nervous disorders.

Description

Riboflavin, also called vitamin B₂, is a water-soluble vitamin. The recommended dietary allowance (RDA) for riboflavin is 1.7 mg/day for an adult man and 1.3 mg/day for an adult woman. The best sources of this vitamin are meat, dairy products, and dark green vegetables, especially broccoli. Grains and legumes (beans and peas) also contribute riboflavin to the diet. Riboflavin is required for the processing of dietary fats, carbohydrates, and proteins to convert these nutrients to energy. Riboflavin is also used for the continual process of renewal and regeneration of all cells and tissues in the body.Riboflavin is sensitive to light. For this reason, commercially available milk is sometimes supplied in cartons, rather than in clear bottles. Riboflavin is not rapidly destroyed by cooking. Milk contains about 1.7 mg riboflavin/kg. Cheese contains about 4.3 mg/kg, while beef has 2.4 mg/kg and broccoli has about 2.0 mg/kg. Apples, a food that is low in all nutrients, except water, contains only 0.1 mg riboflavin per kg.

Causes and symptoms

A deficiency only in riboflavin has never occurred in the natural environment. In contrast, diseases where people are deficient in one vitamin, such as thiamin, vitamin C, and vitamin D, for example, have been clearly documented. Poorer populations in the United States may be deficient in riboflavin, but when this happens, they are also deficient in a number of other nutrients as well. When riboflavin deficiency is actually detected, it is often associated with low consumption of milk, chronic alcoholism, or chronic diarrhea.The symptoms of riboflavin deficiency include:

swelling and fissuring of the lips (cheilosis)
ulceration and cracking of the angles of the mouth (angular stomatitisis)
oily, scaly skin rashes on the scrotum, vulva, or area between the nose and lips
inflammation of the tongue
red, itchy eyes that are sensitive to light

The nervous symptoms of riboflavin deficiency include:

numbness of the hands
decreased sensitivity to touch, temperature, and vibration

Diagnosis

Riboflavin status is diagnosed using a test conducted on red blood cells that measures the activity of an enzyme called glutathione reductase. An extract of the red blood cells is placed in two test tubes. One test tube contains no added riboflavin, while the second test tube contains a derivative of riboflavin, called flavin adenine dinucleotide. The added riboflavin derivative results in little or no stimulation of enzyme activity in patients with normal riboflavin levels. A stimulation of 20% or less is considered normal. A stimulation of over 20% means that the patient is deficient in riboflavin.

Treatment

Riboflavin deficiency can be treated with supplemental riboflavin (0.5 mg/kg body weight per day) until the symptoms disappear.

Prognosis

The prognosis for correcting riboflavin deficiency is excellent.

Prevention

Riboflavin deficiency can be prevented by including milk, cheese, yogurt, meat, and/or certain vegetables in the daily diet. Of the vegetables, broccoli, asparagus, and spinach are highest in riboflavin. These vegetables have a riboflavin content that is similar to that of milk, yogurt, or meat.

Resources

Books

Brody, Tom. Nutritional Biochemistry. San Diego: Academic Press, 1998.

Key terms

Recommended dietary allowance — The recommended daily allowances (RDAs) are quantities of nutrients of the diet that are required to maintain human health. RDAs are established by the Food and Nutrition Board of the National Academy of Sciences and may be revised every few years. A separate RDA value exists for each nutrient. The RDA values refer to the amount of nutrient needed to maintain health in a population of people. The actual amounts of each nutrient required to maintain health in any specific individual differs from person to person.Water-soluble vitamin — Water-soluble vitamins can be dissolved in water or juice. Fat-soluble vitamins can be dissolved in oil or in melted fat.

a·ri·bo·fla·vin·o·sis

(ă-rī'bō-flā'vi-nō'sis), Properly termed hyporiboflavinosis: a nutritional condition produced by a deficiency of riboflavin in the diet, characterized by cheilosis and magenta tongue and usually associated with other manifestations of vitamin B deficiency.

riboflavin deficiency

A condition caused by a relative lack of riboflavin in the diet; riboflavin deficiency is rare, given its wide distribution in foods, and is almost invariably accompanied by deficiencies of other water-soluble vitamins.
Clinical findings
Hyperaemia, erythaema, stomatitis, glossitis, angular cheilitis, seborrhoeic dermatitis, normocytic and normochromic anaemia (which may be accompanied by pure red cell aplasia in the bone marrow).

riboflavin deficiency

A rare condition caused by a lack of riboflavin Clinical Hyperemia, erythema, and pain of oral mucosa, stomatitis, glossitis, angular cheilitis, seborrheic dermatitis Lab Normocytic and normochromic anemia, which may be accompanied by pure red cell aplasia in the BM. See Riboflavin.

单词	riboflavin deficiency
释义	DictionarySeeariboflavinosisEncyclopediaSeeriboflavin riboflavin deficiency Riboflavin Deficiency Definition Riboflavin deficiency occurs when the chronic failure to eat sufficient amounts of foods that contain riboflavin produces lesions of the skin, lesions of smooth surfaces in the digestive tract, or nervous disorders. Description Riboflavin, also called vitamin B₂, is a water-soluble vitamin. The recommended dietary allowance (RDA) for riboflavin is 1.7 mg/day for an adult man and 1.3 mg/day for an adult woman. The best sources of this vitamin are meat, dairy products, and dark green vegetables, especially broccoli. Grains and legumes (beans and peas) also contribute riboflavin to the diet. Riboflavin is required for the processing of dietary fats, carbohydrates, and proteins to convert these nutrients to energy. Riboflavin is also used for the continual process of renewal and regeneration of all cells and tissues in the body.Riboflavin is sensitive to light. For this reason, commercially available milk is sometimes supplied in cartons, rather than in clear bottles. Riboflavin is not rapidly destroyed by cooking. Milk contains about 1.7 mg riboflavin/kg. Cheese contains about 4.3 mg/kg, while beef has 2.4 mg/kg and broccoli has about 2.0 mg/kg. Apples, a food that is low in all nutrients, except water, contains only 0.1 mg riboflavin per kg. Causes and symptoms A deficiency only in riboflavin has never occurred in the natural environment. In contrast, diseases where people are deficient in one vitamin, such as thiamin, vitamin C, and vitamin D, for example, have been clearly documented. Poorer populations in the United States may be deficient in riboflavin, but when this happens, they are also deficient in a number of other nutrients as well. When riboflavin deficiency is actually detected, it is often associated with low consumption of milk, chronic alcoholism, or chronic diarrhea.The symptoms of riboflavin deficiency include: swelling and fissuring of the lips (cheilosis) ulceration and cracking of the angles of the mouth (angular stomatitisis) oily, scaly skin rashes on the scrotum, vulva, or area between the nose and lips inflammation of the tongue red, itchy eyes that are sensitive to light The nervous symptoms of riboflavin deficiency include: numbness of the hands decreased sensitivity to touch, temperature, and vibration Diagnosis Riboflavin status is diagnosed using a test conducted on red blood cells that measures the activity of an enzyme called glutathione reductase. An extract of the red blood cells is placed in two test tubes. One test tube contains no added riboflavin, while the second test tube contains a derivative of riboflavin, called flavin adenine dinucleotide. The added riboflavin derivative results in little or no stimulation of enzyme activity in patients with normal riboflavin levels. A stimulation of 20% or less is considered normal. A stimulation of over 20% means that the patient is deficient in riboflavin. Treatment Riboflavin deficiency can be treated with supplemental riboflavin (0.5 mg/kg body weight per day) until the symptoms disappear. Prognosis The prognosis for correcting riboflavin deficiency is excellent. Prevention Riboflavin deficiency can be prevented by including milk, cheese, yogurt, meat, and/or certain vegetables in the daily diet. Of the vegetables, broccoli, asparagus, and spinach are highest in riboflavin. These vegetables have a riboflavin content that is similar to that of milk, yogurt, or meat. Resources Books Brody, Tom. Nutritional Biochemistry. San Diego: Academic Press, 1998. Key terms Recommended dietary allowance — The recommended daily allowances (RDAs) are quantities of nutrients of the diet that are required to maintain human health. RDAs are established by the Food and Nutrition Board of the National Academy of Sciences and may be revised every few years. A separate RDA value exists for each nutrient. The RDA values refer to the amount of nutrient needed to maintain health in a population of people. The actual amounts of each nutrient required to maintain health in any specific individual differs from person to person.Water-soluble vitamin — Water-soluble vitamins can be dissolved in water or juice. Fat-soluble vitamins can be dissolved in oil or in melted fat. a·ri·bo·fla·vin·o·sis (ă-rī'bō-flā'vi-nō'sis), Properly termed hyporiboflavinosis: a nutritional condition produced by a deficiency of riboflavin in the diet, characterized by cheilosis and magenta tongue and usually associated with other manifestations of vitamin B deficiency. riboflavin deficiency A condition caused by a relative lack of riboflavin in the diet; riboflavin deficiency is rare, given its wide distribution in foods, and is almost invariably accompanied by deficiencies of other water-soluble vitamins. Clinical findings Hyperaemia, erythaema, stomatitis, glossitis, angular cheilitis, seborrhoeic dermatitis, normocytic and normochromic anaemia (which may be accompanied by pure red cell aplasia in the bone marrow). riboflavin deficiency A rare condition caused by a lack of riboflavin Clinical Hyperemia, erythema, and pain of oral mucosa, stomatitis, glossitis, angular cheilitis, seborrheic dermatitis Lab Normocytic and normochromic anemia, which may be accompanied by pure red cell aplasia in the BM. See Riboflavin.
随便看	african-americans in louisiana higher education african american slang african-american slang african americans on wheels african american special interest group african americans reach and teach health ministry african american student academic services african american student advisory council african american student development african american student leadership institute african american student overnighter african american students foundation african american studies african american studies and research program african american studies department african american studies minor african american studies program african american study of kidney disease and hypertension african-americans united in science african american theatre ensemble african american tobacco education network african american transsexuality african american travel and tourism association african american united fund african-american unity caucus