welcome to the last section in the last section we're going to cover folate as well as vitamin B12 so folate is also sometimes referred to as B9 I'll be referring to it mainly as folate today it is an essential co-enzyme as you've heard many times today it is involved in methylation reactions which are essential for this synthesis of any new compound in the body a methyl group is a ch3 group and to synthesize new compounds we have to have folate present in order to do so you see on the image here tetrahydro folate this is thf this is going to be the most active form of the co-enzyme that inv includes folate in it and before moving on I do think it's a important distinction to differentiate folate versus folic acid they're often referred to as the same thing and they aren't folate is going to be the natural occurring form of the vitamin which is found in our food sources like the green leafy vegetables the beans the lentils and such it is inactive okay so it is not in its active form when we consume it our bodies have to activate it in some way shape or form folic acid on the other hand is the synthetic or the man-made version of the vitamin it is more stable and it is also easier for the body to absorb which is a bit unique it's often added to fortified Foods so grain products cereals and the like folic acid is already active Okay so folate found in our Foods inactive folic acid man-made added to Foods added to supplements and already in its active form that will become an important distinction as we progress in the discussion today so moving on let's look at some key functions DNA synthesis and cell division are very very important and the creation of any new compound is important right so it begs to stand that DNA is going to be a big part of uh the picture if we're creating new DNA we have to have folate present it is very helpful for any cells that are rapidly turning over particularly in the embryonic state so when the fetus is developing when a woman is pregnant folate becomes extremely important for the appropriate synthesis of the neural system and the neural tube it's also important for red blood cell synthesis red blood cells are cells that turn over very quickly and anytime we have this turnover occurr uring quickly folate becomes important to synthesize those the final product and homosysteine homocystine is a compound which we'll look at in a few slides which is a harmful compound for us folate as well as B12 and B6 can help break that compound down in the body so those are the functions I've chosen to highlight and I'll refer to them on the next few slides in terms of what can happen if we're deficient in the nutrient okay okay so food sources you can read through these I alluded to those on the previous slide whenever I was discussing the differences between fol folate and folic acid excuse me uh I will comment that orange juice is often fortified as well so we add it an extra amount to it it already contains a bit of it and we add a bit more to it but these would be the food sources that are the highest in full age uh you know what one other function comes to mind that I didn't include on the slide but it is worth mentioning to you all here it's also been a nutrient that has been found to be helpful for neurotransmitter synthesis so neurotransmitters these are compounds like dopamine norepinephrine seratonin and Folly seems to have a role with the synthesis of those compounds there are some links within those neurotransmitters and the condition depression especially chronic depression so there's some interesting research out there now looking at folate in terms of a adjunct treatment for chronic depression there's even genetic tests that can help identify if someone is metabolizing fully well or not that gets a little bit beyond the scope of our class but I thought it was worth mentioning if you yourself or anyone who you know has heard about this topic methylated folate for depression then it is certainly something out there but we'll keep it fairly basic for our semester so let's go ahead and take a look at some of the deficiency States and we'll relate them back to these key functions so the first one I wanted to discuss are neural tube defects the main neural tube defect out there is spinabifida and it is on the image here where the spinal cord doesn't doesn't fuse well and as a result we have the spinal fluid creating an out pouch at some point in the VT column you can see on the picture of the baby here this has occurred in that lower area and what we would find if he is to survive then he will be paralyzed from that point on down so it's going to affect the nervous system development from that point on this deficiency can occur as I mentioned earlier in cells that are turning over quickly and one spot that we find where cells are turning over extremely quickly is during embryonic development particularly the first month of pregnancy this is why it is so important for prenatal vitamins to be taken by women who are planning on pregnancy or might become pregnant prenatals will have a higher amount of this nutrient in it to prevent against neural tube defects interesting fact we have actually fortified Foods in the United States with folic acid the active form of the vitamin since the 1980s to prevent against and decrease the rates of conditions like spinabifida and it has made a difference we have seen much lower rates than prior to the fortification uh just another side note here this is why planning pregnancies is ideal that first month can be so crucial for many important systems of the body including the nervous system on the right hand side you see macro partic anemia pictured so with folate being very important for Rapid cell division it's going to be involved with red blood cells which are very quickly uh they have a very short halflife or short life excuse me so they're always dividing and then synthesizing new red blood cells from that so on the image the left hand side shows you what's occurring if folate is present we have the nice red blood cells being created if we're deficient in folate the nucleus cannot form as well DNA is not synthesized as efficiently leading to a large cell literally macr site meaning large cell that large cell isn't going to work well it's going to not be able to carry oxygen to the tissues as it should so those are a few deficiencies related to the the functions I outlined the third one to mention here is cardiovascular disease risk so the slide here walks us through the compound homosysteine homosysteine is a compound that's created in our bodies naturally through metabolic reactions and in a perfect world if we're eating appropriate amounts of our B vitamins the B vitamins can break it down further and basically help to eliminate it out of the body if we're not consuming adequate B vitamins particularly this one folate then that homocysteine compound can build up and build up and build up and when we get to a point where it's high it can start damaging the arterial wall which is what you see Illustrated here on the slide that can lead to a proliferation of bad cholesterol and even things like heart attacks and strokes what about a toxicity you're probably thinking well heck this is a really good vitamin we want to take it in supplement form we certainly can go this route but we do need to be careful and not go too high so I mentioned to you earlier folic acid it's already active too much folic acid can inadvertently mask what's called a B12 deficiency uh prenatal vitamins are generally capped at about 800 micrograms of the nutrient we don't really want to be taking in too much and I'll give you a little bit of background on this and then I'll discuss it in the the next few minutes as well our last vitamin of the day which is vitamin B12 its main function is to help activate folate okay so I've alluded to this concept where folate is not active folic acid is active so B12 helps to activate folate to its more active form and as a result folate can do all of those things it can help with neural tube development it can help with the red blood cells help with fol or homocysteine etc etc so the the thought here is well great but what if the individual truly has a B12 issue so let's say they're not consuming B12 and that's really the reason why fate isn't being activated and why we're seeing the large blood cells and why we're seeing higher levels of homosysteine then giving a folic acid supplement really isn't going to do much good right so we're going to help out in terms of the DNA synthesis and the red blood cells but we're not treating the underlying condition which is truly a B12 deficiency so the key take ways here B12 activates folate so that folate can serve its various functions giving folic acid which is already active can clear up some of the symptoms of a folate deficiency but it can allow an underlying B12 issue to fester and continue and continue and that's really not a good thing as we'll learn shortly so that's about 10 minutes or so on folate we're going to wrap up with talking about another very important nutrient and that's vitamin B12 look at how big it is it's one of our largest vitamins and unique to it it has a mineral at its Center it has Cobalt there are two forms as you see all generally refer to it as a whole so B12 being cobalamin I mentioned this just a few seconds ago main function we need it for folate function okay it's a big big deal it helps to activate folate in the body and as a result it helps with that red blood cell synthesis DNA synthesis through the actions of folate as well as actions on its own the image that you hear or that you see here excuse me walks you through this process we have inactive folate on the top when B12 is present it can help to eliminate the methyl Group which in essence activates folate and then both of those nutrients folate and b12 with that extra methyl group can now do their various functions so folate goes on with the neural tube with the red blood cells B12 assists with those and it also has some functions with the neurological system so very important takeaway here my second bullet point without adequate B12 we do see the macro siic gemia and that's because folate cannot be activated and cannot synthesize those nice red blood cells all right so I'd like you to take a second here and put me on pause and read over this slide I really tried to put into words the relationship between folic acid and vitamin B12 and why supplementation is not a good idea if we're really needing to treat a B12 problem so take a minute and pause me here all right so very important to differentiate if it's truly a vitamin B12 issue or if it's a folate issue as the treatment will differ if an individual truly has a folate problem then certainly giving folic acid will treat it however if they truly have a B12 issue then giving folic acid will help some of the side effects but it's not going to be treating the underlying problem which is B12 all right I really really have tried to hit that home there's a great section in your book as well if you'd like to read a little bit more on that so one are some of these other functions I've been talking a lot about the functions of folate with red blood cells and the neural tube does vitamin B12 have other functions and yes yes it does it can help with homosysteine breakdown so that compound that that we saw a few slides ago it also can break down homos B12 can also break down homosysteine it plays a key role with the development of nerve cells you've probably learned about myelin sheaths around our nerve cells vitamin B12 is one of the primary components of those myin sheaths one of the early signs of deficiency is tingling in the extremities and that's due to the myin sheath being broken down and not transmitting those neural neural messages as efficiently looking down here at the food sources uh big Point here only naturally found in animal Foods okay we often have to add this to foods to get them out higher so if you're thinking about who might be at risk vegans are are a classic group if they're not consuming any animal products then they generally are are a bit lower in B12 status when I say fortification we do add it to some of our plant-based foods like the whole grain or I'm sorry the enriched grains and you'll also find it with packaged Goods however we don't find that the fortification adds back as much as is naturally found in certain foods so a lot of times folks who are doing completely plant-based diets will actually need a supplement of B12 all right so I'd like to now show you a short video that walks you through vitamin B12 absorption and then we'll talk about some of the key highlights vitamin B12 also known as cyanocobalamin is a complex vitamin containing the mineral Cobalt the primary functions of this member of the B vitamin family which is closely related to another B vitamin folate are the synthesis of DNA preventing macro ciic anemia and maintaining healthy nervous tissue to absorb vitamin B12 the vitamin must first be released from the animal protein to which it is attached in Foods this first step occurs in the stomach with the help of hydrochloric acid and the enzyme pepsin once released vitamin B12 binds with a molecule Fu called R protein which is produced in the salivary glands and present in stomach secretions and the mass of chewed food mixed with the saliva this R protein B12 complex moves into the small intestine where pancreatic enzymes release the vitamin B12 from its complex the free vitamin B12 quickly binds with another protein called intrinsic factor synthesized in the stomach once the complex is formed it travels to the lower portion of the small intestine called the ilium where the intrinsic factor binds to a receptor site on the brush border the vitamin B12 is gradually absorbed across the intestinal cell membrane where it is transported attached to a specific protein called transcobalamin 2 this complex of protein and vitamin B12 travels through the portal vein to the liver where it later enters the bloodstream to okay I'm going to stop him there and get out of this so a lot of steps have to occur correctly for this nutrient to be absorbed right so if the salivary glands aren't producing enough R protein we have a problem if the stomach isn't acidic enough we have a problem if the stomach isn't making intrinsic factor then we're going to have problems later on in the intestines because that nutrient won't have a binding Factor like intrinsic factor so bottom line when you look at this this is quite complex especially compared to the absorption of the other water soluble vitamins which often don't require any additional proteins to be bound and absorbed they are just directly absorbed into the bloodstream as a result of these steps as well as some of the food sources that we find it in it's no surprise that deficiency can be common so let's learn about who's at risk for deficiency and Y first off older adults older adults tend to have not as much hydrochloric acid produced in the stomach so less acidity and that acidity is especially important for helping to get vitamin B12 bound to that R protein so we have to have an acidic medium intrinsic factor is another compound that is essential so if the stomach as we age isn't making as much intrinsic factor then there's a bit more of a risk for deficiency State according to your book about 30% of older adults have what's called atrophic gastritis which means that the acidity and the intrinsic factor isn't isn't as present as is needed for appropriate B12 uh breakdown digestion and absorption another group that's at risk is vegans due to the lack of animal products this is generally found in animal Foods individuals who have gi conditions or problems within the GI system such as irritable bow syndrome or Crohn's disease celiacs disease look at all the things that have to work appropriately for it to be absorbed so if things are moving through too quickly that will definitely play a role couple of other groups that are worth mentioning individuals who take a lot of anti acids so if we're taking a lot of anti acids we're neutralizing the acidity in the stomach that's not great for or B12 also gastric bypass patients with the gastric bypass surgery we're bypassing the stomach in essence and hooking on a little bit later within the small intestine and intrinsic factor isn't going to be secreted as well and can't bind as well to the vitamin so I've summarized a slide here with some of the key takeaways of vitamin B12 deficiency either poor intake or problems with absorbing it are the two main causes so poor intake would be the vegan group or someone who has a very poor diet and isn't consuming isn't consuming much food and when I talk about vegan diet a vegan diet can be a very well planned diet where they are getting in enough fb12 it's just an intentional Focus that individuals have to make so not all vegan diets are low if we're taking in proper supplementation and and fortification of foods we can get it with malabsorption here are some of the highlights the acidity is not as strong uh the enzymes may not be working I mentioned the gastric bypass surgery what can occur also is this pernicious anemia and this is specific to that intrinsic factor so if I'm aging and over time I'm not making as much intrinsic factor then what will occur not going to absorb B12 as well there's less intrinsic factor and that in essence will lead to a state of anemia so we have those large red blood cells being created and that makes sense right so it's a few steps away but I hope you can see that connection if we're not getting enough B12 absorbed into the body we're then not activating folate and as a result folate cannot help with the red blood cell division so we have these larger red blood cells cells being formed the term pernicious just means very harmful type of anemia these are all outlined in your ebook so I certainly recommend to spend some time being comfortable with the potential causes of deficiency symptoms anemia like symptoms initially fatigue shortness of breath however B12 problems can progress into nerve problems paresthesia which is the loss of feeling in the extremities and that's related to that milein sheath it often will start as a tingling in the extremities and then ultimately lead to a scenario where people cannot feel their fingers or their toes can also lead to higher homocysteine levels as I've alluded to a few times so what do we we do for treatment with this well just some FYI we often will do injections of B12 uh because we can byass the complex absorption Pathways so if I give you an injection it's going to go straight through into the muscle which can then be diffused into the blood and it gets sent around the system as it needs to sometimes they'll give very very high amounts sublingually so putting a tablet under the tongue as we have a good capillary system under the tongue to absorb it so that's an option as well but generally you'll find that the injections are what most Physicians will recommend toxicity of the vitamin I didn't really mention is there's not much out there toxicity would really be rare and it would only be in those cases if too much is injected in some way shape or form all right so in your textbook they also discuss some vitamin like compounds like choline and toine however I'm keeping the presentation as well as our content specific just to the B vitamins eight of them and vitamin C just because I think these are the essential ones these are the ones to be familiar with you can certainly read through some of the vitamin light compounds that are out there but you will not be seeing those on exams so to wrap it up I know it's a lot of content thrown at you the book is fantastic and breaking it down and providing you with more information about each and every vitamin I've posted a Blackboard article over uh well basically the eating healthy for your eyes it's about antioxidant status and folate and other nutrients for the eyes and I strongly strongly encourage you to work up or work through excuse me some of the mastering quizzes so pull up that study area and work through these quizzes uh once you get a handle on these vitamins then you you it it's very neat so like you almost remember them for life however the learning curve is a little bit greater as you probably not studied these to this extent before so do whatever you need to do in terms of setting up a study guide for yourself or doing flash cards but do start to get comfortable with the vitamins the last thing that I'll leave you with is that a marginal or mild deficiency may not result in visible symptoms for you and I but it can increase susceptibility to health issues so for example over time not consuming enough vitamin C can increase risk of cancer with full8 and b12 if we're low over time that can increase the risk of cardiovascular disease so we're often looking at these as a more uh temporal aspect so over time what does a deficiency do in the body all right so that is it like I said it's a lot so spend some time with it and then work through some of those practice quizzes thanks for listening