 Hello everybody, let us start our class again. Last few classes we have been dealing with the vitamins, the fat soluble vitamins and a few of the water soluble vitamins and we have been seeing how they affect the body even with the small quantities which are to be taken into our body. So, let us see some more water soluble vitamins today. The vitamin B12 which is a very important vitamin called as cyanocobalt amine because it contains cobalt in its structure. So, this is synthesized by the body bacteria, fungi and other lower organisms therefore, it can be synthesized in the large intestine of our body and the role of vitamin B12 is it plays an important role in folate metabolism or the folic acid metabolism which we were talking about in the last class and maintenance of myelin sheath. Since folic acid is very important for the formation of myelin sheath indirectly, the B12 also is very important for the formation of myelin sheath. This myelin sheath is present on the nerves and it is also very important for RBC formation because vitamin B12 again is required for maturation of RBCs. So, again deficiency of my vitamin B12 will stop the maturation at the megaloblastase and the cells become larger therefore, the circulating number of cells will decrease it causes anemia which is called as pernicious anemia. Now, deficiency of vitamin B12 see this pernicious anemia it causes nerve degeneration and weakness then because it is involved with the nerves you get a tingling sensation or numbness in the extremities of the body that means, the ends of the hands and the toes you have a tingling sensation and numbness which is called as parastitia. Then it may also cause paralysis and death so, the since it is similar to the folic acid the symptoms also look similar to folate deficiency and you will not know whether to supplement folic acid or B12 therefore, generally both folic acid and B12 are supplemented. Usually 95 percent is due to decreased absorption because the vitamin B12 absorption requires an intrinsic factor if you remember we were talking about it in the digestion absorption and utilization of nutrients. So, this intrinsic factor is produced in the blood and because of the intrinsic factor the vitamin B12 is bound the intrinsic factor itself binds the vitamin D B12 and takes it into the circulation therefore, when intrinsic factor is not produced in the stomach may be due to some surgery of the stomach like gastrectomy or partial gastrectomy intrinsic factor is not produced and therefore, B12 is not absorbed. So, 95 percent of the deficiency is because of the deficiency of the intrinsic factor where absorption does not occur. Then A-chlorhydria A-chlorhydria is when the gastric acid is not produced in the stomach so, it requires a medium of acidity also for absorption. So, when gastric acid is not produced A-chlor that means not even a little amount of gastric acid is produced. So, this also causes B12 deficiency and this is generally seen in elderly people. So, how to get the vitamin B12 into the body? So, the only way is to get injections of B12 intravenously. So, this is the only way to make up the B12 level in the blood. Now, it takes almost 20 years for a deficient diet to see the effect on the nerves. Now, four sources of vitamin B12. So, this vitamin is synthesized by bacteria, fungi and algae and since the absorption is taking place only in the stomach, though it is synthesized in the large intestine, the absorption does not occur. Therefore, there is no use of getting synthesized in the large intestines and the main source of vitamin B12 is only animal products. So, it is not available in the plant products. The animal products are the only source of vitamin B12. Therefore, in non-vegetarians the deficiency is very low whereas, vegetarians can find the deficiency more frequently. Now, the recommended dietary allowance is 1 microgram per day for adults and elderly and 1.2 micrograms per day in pregnant women. So, these are the food sources of vitamin B12. The next vitamin is vitamin C or it is also commonly called as ascorbic acid and this vitamin is synthesized by most of the animals, but in humans it is not synthesized. So, we have to supplement through diet and decreased absorption with high intake. So, taking that vitamin D deficiency can be covered you if you take more the absorption will be decreased and if it is an excess amount since it is a water soluble vitamin again it gets excreted from the body. Functions of ascorbic acid it is very important in the formation of collagen and this collagen is the maximum amount of protein that is present in our body and collagen helps to keep the bones, skin, teeth and blood all blood vessels everything everywhere every tissue in the body requires collagen. So, to keep intact collagen is required therefore, this collagen is based on the ascorbic acid and ascorbic acid is so important and then ascorbic acid acts as an antioxidant other than vitamin A vitamin E ascorbic acid is another important antioxidant. So, it helps to reduce the risk of chronic diseases like heart disease and cancer and it keeps the immune system healthy. So, generally what to there is a folklore saying that you eat vitamin C your cold will go, but the cold does not go with vitamin C intake it happens because the resistance power is increased by taking vitamin C that means the immunity is increased therefore, the cold producing bacteria will be inhibited then it is essential for iron absorption when iron is taken alone the absorption is very low. So, iron requires an acid medium for absorption therefore, whenever a food rich in iron is taken if you supply vitamin C along with it the iron has to be converted from ferric to ferrous form in order to cross the boundaries of the walls of the intestines. So, here vitamin C helps it to cross the layers of the intestines. So, that is why vitamin C is very important in absorption of iron. Now, deficiency of vitamin C it causes scurvy and scurvy is very age old or disease when it was recognized when during the second world war when all the people who are fighting have gone into a deficiency of vitamin C then they were just supplied with lime and they have seen that the symptoms have gone. That means they have said that vitamin C is very important for the collagen formation and it starts bleeding if you do not provide sufficient amount of vitamin C. So, deficient diet if it is there for 20 to 40 days then you can see the deficiency symptoms of vitamin C. So, the symptoms are fatigue and pinpoint hemorrhages. Pinpoint hemorrhages is you see all dot like hemorrhages and you find red spots on the skin where there is breakage of the capillaries and the blood is seen under the skin. This is pinpoint hemorrhages then you have bleeding gums and joints and hemorrhages in many parts of the body because the vitamin C is a very important nutrient for the collagen formation in the body and I told you collagen is present in almost every tissue of the body. Then it is this generally this is associated with poverty and rebond scurvy is when there is a sudden halt of vitamin C and you give a high levels of vitamin C supplements there is the scurvy is again a rebond. This is also an important factor that you cannot give high amounts of vitamin C for treating this scurvy. So, scurvy looks like this it again causes beading of the ribs. So, we have seen in the vitamin D deficiency where it looks like a necklace, but here it is the opposite way where the beading is there and this is called as corbutic rosary whereas in vitamin D we call it as rickettsia rosary and you can see the follicular hemorrhages wherever the hair follicles are there you can see all the points of the blood coming out. So, that is follicular hemorrhage caused because of vitamin C deficiency. Now the food sources of vitamin C we do not have to find out very rich sources to have vitamin C our simple goa and amla are very rich in vitamin C. So, you have one goa per day you can meet the vitamin C requirement then you have all the citrus fruits are rich in vitamin C and potato when you eat along with the skin you boil potato along with the skin then you get vitamin C then green pepper, cauliflower, brocoli, strawberry then lettuce and spinach all these are good sources of vitamin C, but vitamin C is lost very easily through cooking. So, it gets oxidized and it is sensitive to heat and sensitive to iron, copper and oxygen whenever you cook in iron vessels or copper vessels and when it is openly cooked all these stages the vitamin C is lost. These are the rich sources of vitamin C. Now recommended dietary allowances for vitamin C they have recommended 40 milligrams of vitamin C per day, but actually the amount that is required is very less it may it is only 10 to 20 milligrams per day, but taking the cooking losses the oxidation and all into considerations they have given as 40 milligrams. So, that at least the 10 to 20 milligrams is absorbed into the body and for a pregnant woman it is 60 milligrams per day and the last p complex vitamin is the colon and this has got lot of importance in the latest days it is a newest essential nutrient they have recognized that it is also one of the essential nutrient all the tissues again contain colon and it is a precursor for acetyl colon acetylcholine is a precursor I mean it is a neurotransmitter which is very important for the contractions and relaxations of the spincters and closure of the spincters therefore it is very important and this is a precursor for phospholipids. Phospholipids again are present in the brain and some role in homocysteine metabolism. Now, the food sources of colon it is widely distributed present in milk, liver, eggs, peanut and lecithin that is added to food and this lecithin is present in egg, egg yellow contains lot of lecithin. So, when you add egg you can get colon. Now, deficiency of colon it can also lead to a fatty liver, deficiency can lead to fatty liver and this fatty liver is called as non-alcoholic fatty liver disease because generally when alcohol is consumed in large quantities people have the tendency to develop fatty liver, but here with colon deficiency you can get non-alcoholic fatty liver disease and the most common symptoms of colon deficiency are fatty liver and hemorrhagic kidney necrosis that means the cells of the kidney die and they have hemorrhage. So, this is about the vitamin C and the colon that those two vitamins are very important in the body. Since vitamin C is present in all the tissues as collagen and if this is disrupted then there is hemorrhage and you have seen that colon also causes hemorrhage and fatty liver in the body. So, we have seen all the water soluble vitamins starting from the vitamin B1 to the colon along with the vitamin C and these are essential whatever is the requirement the body takes up and the excess amount is excreted from the body. Generally there is no toxicity, but sometimes some of the B complex vitamins have toxicity, but that is very rare and the occurrence of these B complex vitamins in food is very common and if one has a balanced diet one can get all the B complex vitamin in the diet without any deficiency symptoms. Thank you.