Vit B3 NIACINE.pptx

Vit B3 NIACINE.pptx

1. Dr. Anuj Singh Asst. Professor Community Medicine Dept. UIMS, Prayagraj

2. Contents:- Source Function Deficiency Prevention &

3. History  The term niacin (vitamin B3) is considered a generic term for nicotinic acid and nicotinamide (also called niacinamide ). The vitamin was once called the anti–black tongue factor because of its effect in dogs. Pellagra was especially prevalent in the Southern United States where corn (which contains a relatively unavailable form of niacin) was a main dietary staple in the early 1900s.In 1937 Elvehjem isolated the vitamin, for cure of both pellagra and black tongue.

4. Vitamin-B3 Niacin Vitamin B3 or Niacin is a water-soluble  B vitamin , which is also known as : “ Pellag r a preventing factor " Niacin is pyridine -3-carboxylic acid It is a odourless whi t e crystalline compound It is stable to heat & acid

5. The two most common forms of niacin in food and supplements are nicotinic acid and nicotinamide The body can also convert- Tryptophan (AA ) Nicotinamide Nicotinamide is the amide form of nicotinic acid 1 mg of niacin is formed from 60 mg of tryptophan

6. Niacin is water-soluble so that excess amounts the body does not need are excreted in the urine. Niacin works in the body as a coenzyme, with more than 400 enzymes dependent on it for various reactions . Niacin helps to convert nutrients into energy, create and repair DNA, and exert antioxidant effects. 

7. Function s:- Niacin i s import a nt f or pr o per bl o od circulation . For healthy functioning of nervous system . It maintains the normal functions of GI tract . It i s essential f or the metabolism o f prote i ns and carbohydrates.

8. 5) It helps to maintain a healthy skin . 6) It helps to increase the flow of blood to the peripheral capillary system . 7) This vitamin also essential for synthesis of the sex hormones namely oestrogen, progesterone testosterone as well as cortisone, thyroxin and insulin. Functions cont..

9. Dietary sources : Rich sources of niacin are liver, meat, fish, legumes, whole grain cereals and dried yeast, tea & coffee Poor sources: Fruits , vegetables and corn Zein is major protein present in corn Zein is very low in tryptophan –provitamin of niacin

10. RDA Men 15-20 mg Women 13-15 mg Lactating women 20 mg Children 8-15 mg Infants 650 mcg

11. Metabolism Absorption: It is absorbed from upper small intestine It occurs by simple diffusion Transport: It enters portal circulation, reaches general circulation & enters all cells Storage: It is not stored in significant amounts in tissues In tissues, it gets converted into its coenzymes

12. Deficiency : Causes: Inadequate intake Alcoholism Impaired absorption Antivitamins : Chronic administration of drugs such as isoniazid (used in T.B) & 6-mercaptopurine ( Leukemia )

13. 5. Pyridoxine deficiency: It associated with impaired conversion of tryptophan to niacin due to decreased activity of PLP dependent enzyme, kynureninase 6. Hartnump disease: Associated with defective absorption of tryptophan

14. Deficiency symptoms A mild deficiency of niacin may result in - Coated tongue. Sores in the mouth. Irritability. Nervousness. Skin lesions. Diarrhoea. Memory loss . Insomnia. Chronic headaches. Digestive disorders. Anaemia.

15. Severe prolonged deficiency may cause Neurasthenia (weakness of the nerves), Mental disturbances. Depression. Mental dullness. Disorientation.

16. Deficiency of niacin leads to the clinical condition called pellagra Pellagra is caused by the deficiency of tryptophan & niacin More common in women – because tryptophan metabolism is inhibited by estrogen metabolits Symptoms: Dermatitis: In early stages, bright red erythema occurs, in feet, ankles and face

17. Increased pigmentation around the neck is known as Casal’s necklace Dermatitis is precipitated by exposure to sunlight Diarrhea: Diarrhea may be mild or severe with blood & mucus Leads to weight loss Nausea & vomiting Dementia: Irritability, inability to concentrate & poor memory

18. Pellegra. Niacin deficiency. Dermatitis, diarrhea, dementia.

19. CASAL NECKLACE

20. Same patient after niacin treatment.

21. Healing and therapeutic properties

22. 1. Pellagra Administration of small amounts of up to 10mg or 10000 mcg per day is sufficient to cure endemic pellagra.

23. 2. High blood pressure Niacin has been used as vasodilator to dilate blood vessels and to correct blood pressure changes.

24. 3. Heart-Related Disorder Niacin has been fo u nd t o prov i de rel i ef in angina pectoris. It has also been found useful in case of cerebral thrombosis caused by blockage of blood vessels of the brain due to clots of blood.

25. 5. High Blood Cholesterol Niacin has proved to have a remarkable effect in reducing high blood Cholesterol

26. 4. Diarrhoea The administration of niacin in therapeutic doses along with other B vitamins can cure such ailments.

27. 6. Migraine Niacin has been f o und us e f ul i n t reat i ng migraines. Migraine can be cure by taking large doses of niacin.

28. Precautions The use of la r ge d o ses of ni a cin f or l o n g periods cause release of histamine .

29. Toxicity: Toxicity when eating foods containing niacin is rare, but can occur from long-term use of high-dose supplements. A reddened skin flush with itchiness or tingling on the face, arms, and chest is a common sign. Flushing occurs mainly when taking high-dosage supplements in the form of nicotinic acid, rather than nicotinamide .

30. Toxicity: cont.. Other signs: Dizziness Low blood pressure Fatigue Headache Upset stomach Nausea Blurred vision