1. Riboflavin deficiency and toxicity
Domina Petric, MD

2. Riboflavin deficiency
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

3. Signs of riboflavin deficiency overview
Organ system/function
Signs
Appetite
Decreased
Growth
Dermatologic
Cheilitis, stomatitis
Muscular
Weakness
Gastrointestinal
Inflammation, ulcer
Skeletal
Deformities
Vital organs
Hepatic steatosis
Erythrocytes
Anemia
Nervous
Ataxia, paralysis
Males
Sterility
Females
Decreased fertility
Fetal
Malformations, death
Retinal
Photophobia
Corneal
Decreased vascularization

4. Factors contributing to riboflavin deficiency
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

5. Inadequate diet
Inadequate diet is the most important cause of riboflavin deficiency.
This involves the low consumption of milk, which is the most important source of the vitamin available in most diets.
In industrialized countries, riboflavin deficiency occurs most frequently among alcoholics, whose dietary practices are often faulty, leading to this and other deficiencies.
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

6. Enhanced catabolism
Catabolic conditions associated with illness or vigorous physical exercise and involving nitrogen loss increase riboflavin losses.
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

7. Alcohol
High intakes of alcohol appear to antagonize the utilization of FAD from foods.
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

8. Phototherapy
Phototherapy of infants with hyperbilirubinemia often leads to riboflavin deficiency (by photodestruction of the vitamin) if such therapy does not also include the administration of riboflavin.
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

9. Exercise
Physical exercise can produce abnormalities in a variety of biochemical markers of riboflavin status such as increased erythrocyte glutathione reductase activity coefficient and reduced urinary riboflavin.
There is no evidence that such abnormalities lead to impairments in physiological performance.
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

10. Other
Reduced riboflavin status among some women using oral contraceptive agents.
Patients receiving diuretics or undergoing hemodialysis experience enhanced loss of riboflavin (as well as other water- soluble vitamins).
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

11. Deficiency signs
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

12. Deficiency signs
Uncomplicated riboflavin deficiency becomes manifest in humans only after 3 to 4 months of deprivation of the vitamin.
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

13. Deficiency signs cheilosis/cheilitis angular stomatitis glossitis
hyperemia and edema of the oral mucosa
seborrheic dermatitis around the nose and mouth and scrotum/vulva
normocytic, normochromic anemia with reticulocytopenia, leukopenia and thrombocytopenia
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

14. Cheilosis Sabkadentist.com
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

15. Seborrheic dermatitis
Noskinproblems.com
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

16. Deficiency signs
Riboflavin-deficient patients also experience neurological dysfunction:
Peripheral neuropathy of the extremities characterized by hyperesthesia, coldness and pain, as well as decreased sensitivity to touch, temperature, vibration and position.
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

17. Subclinical deficiency
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

18. Subclinical deficiency
Riboflavin deficiency has been reported to enhance carcinogenesis.
This effect is thought to be due to diminished antioxidant protection, increasing the activation of carcinogens and oxidative damage to DNA, and/or diminished folate metabolism, reducing DNA synthesis, repair and methylation.
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

19. Subclinical deficiency
Subclinical riboflavin deficiency may actually be beneficial under certain conditions.
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

20. Protection against malaria
Because growth of the malarial parasite (Plasmodium spp.) in the erythrocytes of infected hosts causes oxidative stress in those cells, riboflavin deficiency is protective against propagation of the infection.
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

21. Protection against tryptophan deficiency-induced cataract
Riboflavin deficiency has been shown to protect the rat from the cataractogenic effect of a low- tryptophan diet.
The metabolic basis of this effect may involve the lack of formation of a riboflavinyl tryptophan adduct that accelerates the photo-oxidation of the amino acid to a prooxidative form.
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

22. Riboflavin toxicity
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

23. Riboflavin toxicity
The toxicity of riboflavin is very low and problems of hypervitaminosis are not expected.
Probably because it is not well absorbed, high oral doses of riboflavin are essentially nontoxic.
11/13/2018
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc

24. Literature
Combs GF. The Vitamins. Fundamental Aspects in Nutrition and Health. Elsevier Inc
11/13/2018