 Hello everybody welcome back to the class today and we have started with the water soluble vitamins in the previous class and seen the first water soluble vitamin about the thiamine how it plays an important role in the body and how the deficiency causes so much of disturbance in the body. So, let us see the next water soluble vitamin which is the riboflavin and this is named as vitamin B2. So, the functions of riboflavin is it acts again just like thiamine it acts as a coenzyme for metabolism. So, it participates in many energy yielding metabolic pathways like the fatty acids are broken down and burn to energy like many other vitamin B. Riboflavin helps the body to metabolize carbohydrates proteins and fat and riboflavin also protects the health of the body cells and enhances the function of some of the other B vitamins also like niacin and vitamin B12. Now deficiency of riboflavin causes stomatitis and this is also called as the air riboflavinosis that means there is no riboflavin in the diet. So, this causes painful red tongue and sore throat chapped with the fissured lips which is called as chelosis and inflammation of the corners of the mouth which is called as the angular stomatitis. You can find scars in the corners of the lips and there can be oily scaly skin rashes in the scrotum, vulva, filtrum of the lip and the nasolabial folds. So, the eyes can become itchy, watery, blood short and sensitive to light. So, this is how the cracked lips look like which is called as chelosis and you can see all these cracks and the tongue also there is crack and it starts bleeding. So, and you can see the corners of the lips being cracked and becoming ulcerative. So, which is called as angular stomatitis. Now, deficiency of riboflavin due to interference with iron absorption riboflavin deficiency results in anemia. So, it is these cells when there is riboflavin deficient they look normal cell size and normal hemoglobin, but they are normo-cythemic. So, that means the volume of the RBC cell is decreased. So, this is distinct and from anemia which is caused by deficiency of folic acid or cyanocobalamin or vitamin B12. These two vitamins also cause anemia where the RBC does not mature and it remains as a megaloblast. So, the size of the RBC is increased in its volume and deficiency of riboflavin during pregnancy it can result in birth defects including congenital heart defects and limb deformities. The various symptoms of the deficiency of riboflavin you can see that you have sore red eyes, then angular stomatitis in the mouth, the glossitis of tongue, then key losses of lips there are cracked and start bleeding and scrotal dermatitis. Now, food sources of riboflavin the rich source is milk, but it has to be stored in a dark bottle when it is exposed to sunlight riboflavin gets oxidized. Then they are present in ready to eat cereals, then oyster, yeast, vegetables like green leafy vegetables then so it is very sensitive to sunlight and it should be always stored in an opaque plastic container or in a dark container or it can be wrapped with a paper so that sunlight does not affect the riboflavin in the bottle. Then food sources you can see recommended dietary elements for riboflavin again 1.1 milligram for women, 1.4 milligrams per day for men, average intake generally is above recommended dietary elements for a person who takes balanced diet and toxicity is not documented no upper level. So, the third vitamin is niacin which is called as vitamin B3 so this is also called as nicotinic acid or nicotinamide and this again acts as a coenzyme and needed when the energy is being utilized. So, synthetic pathways require niacin especially for the fatty acid synthesis just like the riboflavin. Now, this riboflavin it protects the health of the skin cells and keeps the digestive system functioning normally and it is also required for metabolism of fat. So, the large amounts of niacin can help to lower the LDL and raise the HDL LDL is supposed to be the bad cholesterol and HDL is supposed to be good cholesterol and also the triglyceride levels and cholesterol levels increase in the niacin deficiency. Now, deficiency of niacin leads to a disease called pellagra we also call this disease as a 3D disease or sometimes 4D disease, but generally the fourth D is not very common. So, 3Ds are dementia, diarrhea and dermatitis and this dermatitis is the skin rashes which becomes worse when the body is exposed to sun whatever part of the body is exposed to sun. So, and this occurs in 50 to 60 days and occurs because of the symptoms will be poor appetite, weight loss and weakness and the fourth D which I was mentioning is death when the niacin deficiency is not taken proper care then the ultimate result is the death. Now, pellagra it can be prevented by adequate amount of protein intake. Why protein intake is because the protein the tryptophan is an amino acid which is an essential amino acid from protein and every 60 milligrams of tryptophan is converted into 1 milligram of niacin. Therefore, if you give a protein rich diet naturally you get niacin from the tryptophan then enrichment act of 1941 says you have to give the good protein diet then reach epidemic proportions of the deficiency have reached the southeastern US it was in 1800 to 1930s then they have found that when you give protein rich diet niacin deficiency is decreased. Pellagra looks like this all this area this which is exposed to the sun is the dermatitis you can see it becomes very dark and the there is symmetric appearance of the dermatitis on both sides. So, it looks like a necklace here and you can see both the hands which are affected by the dermatitis. Food sources of niacin are enriched grains ready to eat cereals then you have niacin in beef, chicken, turkey and fish asparagus, peanuts then but it is heat stable so very little cooking losses occur. 60 milligrams of tryptophan can be converted into 1 milligram of niacin so from this we can need about meet about 50 percent of our needs therefore, you give them a proper protein diet 50 percent of niacin requirement is met and niacin in corn is bound by the protein so soaking the corn whenever corn is eaten in large amounts niacin is not available because it is blocked. So, soaking the corn in alkaline solution like lime water will release niacin. Food sources of niacin you have the meat, fish, poultry all the non vegetarian foods have very good amount of niacin then nuts and eggs and milk. Now, recommended dietary allowance for niacin again niacin is related to energy metabolism just like the thymine and riboflavin therefore, the requirement of niacin is again dependent upon the energy requirements according to that for women it is recommended as 12 milligrams men it is 16 milligrams so about 20 milligrams on an average will be sufficient and upper limit is 35 milligrams and there is some toxicity with niacin which results in headache, itching, flushing, liver and gastrointestinal damage. Now, mega dose can lower the LDL and triglyceride and increase the HDL so whenever an individual has increased levels of LDL and triglycerides and low levels of HDL niacin supplementation can improve the condition in that individual. This is about the riboflavin and niacin their food sources and recommended dietary elements is what happens when the riboflavin deficiency occurs what happens when niacin deficiency occurs and what about the excess? Excess generally does not cause any symptoms because all these are water soluble vitamins thank you.