1 00:00:00,012 --> 00:00:04,929 Aside from carbohydrates, fats have been blamed for making us fat. 2 00:00:04,929 --> 00:00:09,058 And certainly, maybe that's an easy thing to correlate. 3 00:00:09,058 --> 00:00:12,934 Fat makes us fat. But if we talk about them as lipids, 4 00:00:12,934 --> 00:00:18,090 maybe it'll be a different story. Just like carbs, fat has gotten a bad 5 00:00:18,090 --> 00:00:21,571 rap. Lipids are an essential part of our diet 6 00:00:21,571 --> 00:00:27,391 we need fat and as i go through the next series of slides remember about what you 7 00:00:27,391 --> 00:00:33,128 eat and think about what it means how is the quality of lipid I consume going to 8 00:00:33,128 --> 00:00:37,131 dictate the quality of my own body withins Lipids. 9 00:00:37,131 --> 00:00:43,049 And just remember, as I said, we need fats, its our storage form of energy, it 10 00:00:43,049 --> 00:00:49,186 helps us digest our foods, its important in breaking, digesting, the essential 11 00:00:49,186 --> 00:00:52,797 the, its, stop So just remember, too, we need fat. 12 00:00:52,797 --> 00:00:58,022 As I mentioned, it's important for our storage of energy, we need it to digest 13 00:00:58,022 --> 00:01:02,347 fat soluble vitamins, and just make our taste, food taste good. 14 00:01:02,347 --> 00:01:06,647 And not all fat is bad. It's the excess fat intake, just like the 15 00:01:06,647 --> 00:01:10,222 excess sugar intake, that's causing the problem. 16 00:01:10,222 --> 00:01:14,733 So let's talk a little bit about different types of lipids, among the 17 00:01:14,733 --> 00:01:18,952 categories of lipids, how we name them and how we identify them. 18 00:01:18,952 --> 00:01:22,220 The simplest form of lipid is the free fatty acid. 19 00:01:22,220 --> 00:01:27,486 These hydrocarbon chains range from 4 to 24 carbons in length with a methyl group 20 00:01:27,486 --> 00:01:30,702 at one end, and a carboxyl group at the other. 21 00:01:30,702 --> 00:01:36,487 The carboxyl end is termed alpha, the methyl end termed omega. 22 00:01:36,487 --> 00:01:41,202 And this technique is useful in naming fatty acids are grouped by degree of 23 00:01:41,202 --> 00:01:45,732 saturation. A saturated fatty acid has no double 24 00:01:45,732 --> 00:01:49,212 bond. All of its carbons are bonded to 25 00:01:49,212 --> 00:01:53,235 hydrogen. Mono-unsaturated fatty acids have one 26 00:01:53,235 --> 00:01:58,634 double bond in their chain. They're sometimes abbreviated as MUFA, or 27 00:01:58,634 --> 00:02:04,563 MUFA, Folic acid as imaged here is found in olive oil and it's an Omega-9 fatty 28 00:02:04,563 --> 00:02:08,031 acid. Omega-9 fatty acids are not considered 29 00:02:08,031 --> 00:02:11,327 essential. Fats because we can make them in the 30 00:02:11,327 --> 00:02:15,402 body, and of course, saturated fats are also not essential. 31 00:02:15,402 --> 00:02:20,577 This omega designation comes from the naming of fats, and it's based on where 32 00:02:20,577 --> 00:02:25,327 that first double bond is. the double bond here is signified with a 33 00:02:25,327 --> 00:02:29,344 red color. If you are unable to see that you can see 34 00:02:29,344 --> 00:02:34,881 the lack of hydrogens in the slight change in shape of the structure. 35 00:02:34,881 --> 00:02:41,171 The simplified image to the right points out the 9 carbon and it's the simplest 36 00:02:41,171 --> 00:02:47,611 counting over, counting over one, two, three, four, five, six, seven, eight, 37 00:02:47,611 --> 00:02:51,172 nine. Nine carbons Omega-9 fatty acid we will 38 00:02:51,172 --> 00:02:56,777 do the same thing for omega threes and omega sixes polyunsaturated fatty acids 39 00:02:56,777 --> 00:03:00,522 have multiple double box in our chain and are abbreviated PUFA, 40 00:03:00,522 --> 00:03:04,927 or PUFA. The malonic acid illustrated here is 41 00:03:04,927 --> 00:03:08,500 found in corn and corn oil and is an essentiall fatty acid. 42 00:03:10,192 --> 00:03:15,259 Essential fatty acids are essential as I mentioned because we can't make them. We 43 00:03:15,259 --> 00:03:20,044 lack the specific saturated enzyme required to make a double bond anywhere 44 00:03:20,044 --> 00:03:23,228 before Carbon 9. So this makes the Omega-3's and 6's 45 00:03:23,228 --> 00:03:27,645 essential, and you'll see potentially marketing campaigns, so you talk about 46 00:03:27,645 --> 00:03:32,199 increasing them in a subsequent lecture. You're going to hear a little bit more 47 00:03:32,199 --> 00:03:36,554 about the healthful benefits of eating more omega-3 fatty acid based foods or 48 00:03:36,554 --> 00:03:40,825 sources of omegO Fatty acids. These dietary sources may vary. 49 00:03:40,825 --> 00:03:46,696 Omega-6's are more abundant in what we consider a western diet, typically we do 50 00:03:46,696 --> 00:03:51,531 consume Omega-6's than 3s, but Mediterranean and fish-based diets will 51 00:03:51,531 --> 00:03:55,555 have more Omega-3's. Again, you'll learn more about that in 52 00:03:55,555 --> 00:04:01,105 the subsequent lecture for this week. The saturation of a fatty acid will 53 00:04:01,105 --> 00:04:07,184 affect it's structure, quality in food, stability and affect in the body. 54 00:04:07,184 --> 00:04:13,539 The more saturated the fat is, the more saturated the food containing that fat 55 00:04:13,539 --> 00:04:19,484 too, the more solid it will be. So think about lard versus butter, versus 56 00:04:19,484 --> 00:04:24,927 margarine, versus olive oil. At room temperature, these will all have 57 00:04:24,927 --> 00:04:29,468 different consistencies. This occurs, put simply, because the 58 00:04:29,468 --> 00:04:34,375 double bonds in saturated fatty acids create a kink in the structure. 59 00:04:34,375 --> 00:04:38,362 These lipids then stack less tightly, resulting in a. 60 00:04:38,362 --> 00:04:42,813 More liquid form. In regard to stability, less saturated 61 00:04:42,813 --> 00:04:48,731 fatty acids are more susceptible to oxidation and they will be more likely to 62 00:04:48,731 --> 00:04:53,095 become rancid. Foods that they're in will be more likely 63 00:04:53,095 --> 00:04:56,687 to Become rancid. We can protect foods higher in 64 00:04:56,687 --> 00:05:01,922 unsaturated fat by adding more antioxidants or preservatives, a natural 65 00:05:01,922 --> 00:05:07,017 one would be vitamin E, as well as keeping these foods cool and reducing 66 00:05:07,017 --> 00:05:12,247 their exposure to air and light. Another way we could actually change the 67 00:05:12,247 --> 00:05:17,806 structure of some of these. Highly unsaturated fatty acid sources. 68 00:05:17,806 --> 00:05:24,396 we've done this to produce a spreadable plant-based product, margarine. 69 00:05:24,396 --> 00:05:30,702 And this semi-solid fat is created through the process of hydrogenation. 70 00:05:30,702 --> 00:05:34,841 In this process, unfortunately, trans-fat synthesis does occur. 71 00:05:34,841 --> 00:05:39,676 And while there are some trans-fats in nature, they're primarily a product of 72 00:05:39,676 --> 00:05:43,288 food processing. In order to create a plant based fat with 73 00:05:43,288 --> 00:05:48,443 this butter consistency the manufacturer removes double bonds of some of the fatty 74 00:05:48,443 --> 00:05:53,306 acids via hydrogenation which. Addition of hydrogen under pressure. 75 00:05:53,306 --> 00:05:58,840 As this product liquif, solidifies, as this product solidifies, we're going to 76 00:05:58,840 --> 00:06:04,066 make some more saturated fat, not all saturated, but we're also going to alter 77 00:06:04,066 --> 00:06:07,647 the structure of some of the unsaturated. Fats. 78 00:06:07,647 --> 00:06:13,729 And if you hadn't had a lot of chemistry or else you put this in a simple terms, 79 00:06:13,729 --> 00:06:19,900 we go from a trans-is to a trans-bond. And here, I've shown images of this, you 80 00:06:19,900 --> 00:06:24,928 can see the difference. So, in the sis form, the carbons go down 81 00:06:24,928 --> 00:06:29,080 to both sides of that bond. In the trans form, become 82 00:06:29,080 --> 00:06:33,237 transcontinental. Trans goes from one side to the other. 83 00:06:33,237 --> 00:06:36,542 And so that's what's happening on these transfats. 84 00:06:36,542 --> 00:06:41,277 Again they are somewhat in nature but really our bodies don't process those 85 00:06:41,277 --> 00:06:46,107 well, and like saturated fat they come with significant pulse concerns if we 86 00:06:46,107 --> 00:06:50,418 over consume trans fats. Fatty acids are also identified by 87 00:06:50,418 --> 00:06:53,726 length. We can elongate short chain essential 88 00:06:53,726 --> 00:06:59,863 fatty acids to longer ones, though it is not a highly efficient process in humans. 89 00:06:59,863 --> 00:07:05,891 We can also desaturate them as the chain link that and only after the ninth carbon 90 00:07:05,891 --> 00:07:12,369 in a short chain acid that you can get from plant or long chain. Omega-3 fatty 91 00:07:12,369 --> 00:07:16,028 acids also come in the shorter or longer chain versions. 92 00:07:16,028 --> 00:07:21,252 This current version is not, efficient, and when we talk about Omega-3 fatty 93 00:07:21,252 --> 00:07:26,238 acids, in health, and if you go to the next lecture, think about the benefits 94 00:07:26,238 --> 00:07:31,055 coming primarily from EPA or DHA. So, if you want to improve outcomes, you 95 00:07:31,055 --> 00:07:35,559 likely want to consume foods, or supplements, with EPA and DHA in it. 96 00:07:35,559 --> 00:07:38,604 And those would be the animal based To form. 97 00:07:38,604 --> 00:07:44,803 You can obtain lineolinic and linolaic Omega-3 and Omega-6 from newer sects of 98 00:07:44,803 --> 00:07:50,274 foods, including veggies, grains, meats, seafood, eggs and milk. 99 00:07:50,274 --> 00:07:55,538 Here is a figure illustrating the types of fat found in your food. 100 00:07:55,538 --> 00:08:02,542 So, take a minute just to compare. So they are lipids, again your going to 101 00:08:02,542 --> 00:08:08,377 find it in the fat portion especially when you are talking about animal foods, 102 00:08:08,377 --> 00:08:12,507 there in the fat of fish or the oil portion of the plant. 103 00:08:12,507 --> 00:08:18,165 And we can compare some of the sources, so lets say we do want to get more omega 104 00:08:18,165 --> 00:08:23,244 three A real abundant source in the oil category would be coconut oil. 105 00:08:23,244 --> 00:08:28,887 An abundant source in some of the animal products would actually be fish.we will 106 00:08:28,887 --> 00:08:34,131 talk about that one in the next slide, but right now looking at the types of 107 00:08:34,131 --> 00:08:39,807 fats you could cook with if you do want to change the profile of your, Profile of 108 00:08:39,807 --> 00:08:42,130 your body. My, one might be canola oil. 109 00:08:42,130 --> 00:08:46,345 Now some people don't like consuming canola oil, it is a processed food. 110 00:08:46,345 --> 00:08:50,727 Another one that's going to give you the biggest bang for your buck is flaxseed 111 00:08:50,727 --> 00:08:53,351 oil. Now flax seed oil, is not something you 112 00:08:53,351 --> 00:08:56,851 can cook with, however. That's why I did not list it first, of 113 00:08:56,851 --> 00:09:01,269 these here, that you can cook with. Normal oils again, is the highest source, 114 00:09:01,269 --> 00:09:05,402 but flax seed oil is a great thing we could add as a salad dressing, or as a 115 00:09:05,402 --> 00:09:08,252 topping later, as opposed to, a cooking oil. 116 00:09:08,252 --> 00:09:15,467 As far as animal based sources go, seafood, especially fish are great 117 00:09:15,467 --> 00:09:23,218 sources of essential fatty acids, Omega-3, especially EPA and DHA And just 118 00:09:23,218 --> 00:09:27,264 like we are what we eat, our animals are what they eat, the livestock that we 119 00:09:27,264 --> 00:09:30,166 choose to consume. And a corn fed cow is going to have a 120 00:09:30,166 --> 00:09:32,852 different fatty acid profile than a grass fed cow. 121 00:09:32,852 --> 00:09:37,105 Same goes for the chicken producing eggs the eggs, not only the chicken will 122 00:09:37,105 --> 00:09:40,890 differ, the meat from the chicken will differ, but the eggs will differ. 123 00:09:42,185 --> 00:09:47,476 Here's a chart illustrating the fatty acid profiles of feed stuffs. 124 00:09:47,476 --> 00:09:53,621 Now, if you are a vegetarian, maybe you don't really want to think about the idea 125 00:09:53,621 --> 00:09:57,906 of eating animals, but maybe you do eat eggs or cheese. 126 00:09:57,906 --> 00:10:04,022 And certainly, the health of an animal. Just like the health of a person is 127 00:10:04,022 --> 00:10:08,067 dictated by what he eats. Alright. 128 00:10:08,067 --> 00:10:10,452 So the next type of fat is the Triglycerides, the lipid Tryglyceride. 129 00:10:12,617 --> 00:10:16,357 Here we see fatty acids in our triglyceride. 130 00:10:16,357 --> 00:10:22,482 It is the storage form of fat and the fat we're going to find in our food. 131 00:10:22,482 --> 00:10:27,547 So it's what's in our fat cells and the fat of our fish, once digest the glycerol 132 00:10:27,547 --> 00:10:30,775 component will be metabolized like a carbohydrate. 133 00:10:30,775 --> 00:10:35,648 And to synthesis the triglyceride if you're going to make fat to store, we do 134 00:10:35,648 --> 00:10:39,933 require a series of condensation reactions that combine a hydrogen. 135 00:10:41,043 --> 00:10:44,535 From the glycerol, to a hydroxyl from a fatty acid. 136 00:10:44,535 --> 00:10:48,558 Making a bond, and water. We now have a compound that can be 137 00:10:48,558 --> 00:10:51,696 stored. It also is important for the taste and 138 00:10:51,696 --> 00:10:54,201 texture of our food. Can then later. 139 00:10:54,201 --> 00:10:57,693 Well, after being sorted, could be used as energy. 140 00:10:57,693 --> 00:11:01,462 It's going to bring in those essential fatty acids. 141 00:11:01,462 --> 00:11:06,322 And it's also important for cell signaling and gene transcription by 142 00:11:06,322 --> 00:11:10,574 releasing those 3 fatty acids. So when we think about function 143 00:11:10,574 --> 00:11:15,561 triglycerides, really encompasses the function of fatty acids that it's 144 00:11:15,561 --> 00:11:19,269 bringing in. Another important lipid is the 145 00:11:19,269 --> 00:11:24,907 phospholipid, so again when we think fat, fat's not, is just fat. 146 00:11:24,907 --> 00:11:30,361 There's a lot of different types of lipids that are in our bodies. 147 00:11:31,781 --> 00:11:38,439 So here, we see what is a cell membrane, it's an illustration and we are going to 148 00:11:38,439 --> 00:11:41,014 make our, stop. Start. 149 00:11:41,014 --> 00:11:46,061 So here we see the illustration of a cell membrane, with its phospholipid 150 00:11:46,061 --> 00:11:51,264 components, including the fatty acids associated with that phospholipid. 151 00:11:51,264 --> 00:11:55,002 And this is where "we are what we eat" comes into play. 152 00:11:55,002 --> 00:12:00,280 Depending on what type fat is in that phospholipid, that will determine what 153 00:12:00,280 --> 00:12:06,076 type of fat what you utilize in the body. All right, so the next category of lipid 154 00:12:06,076 --> 00:12:10,285 is the Lipoprotein and Sterols, including Cholesterol. 155 00:12:10,285 --> 00:12:16,329 There are numerous types of Lipoproteins, all of which have different jobs to do. 156 00:12:16,329 --> 00:12:19,841 the Chylomicron and VLDL we won't focus on. 157 00:12:19,841 --> 00:12:24,540 We will come back to Chylomicrons when we talk about digestion. 158 00:12:24,540 --> 00:12:27,972 Mostly, we're going to talk about LDL and HDL. 159 00:12:27,972 --> 00:12:31,767 Now one thing to clarify, when we talk about good or bad cholesterol, 160 00:12:31,767 --> 00:12:34,717 cholesterol is cholesterol. It's all the same thing. 161 00:12:34,717 --> 00:12:38,837 really when we talk about good or bad cholesterol, we talk about the LDL and 162 00:12:38,837 --> 00:12:43,197 HDL, which are lipoproteins, low density and high density, and we can remember 163 00:12:43,197 --> 00:12:48,261 which one's good or bad by L, standing for lethal, and H standing for healthy. 164 00:12:48,261 --> 00:12:54,036 All right. , So the job of LDL lipoprotein is to 165 00:12:54,036 --> 00:12:59,845 carry those cholestrol molecules from the liver to the cell. 166 00:12:59,845 --> 00:13:05,972 And in doing so, we do at times see deposition of cholestrol and plaque 167 00:13:05,972 --> 00:13:12,649 buildup in the cardiovascular system. On the other hand the job of HDL 168 00:13:12,649 --> 00:13:19,552 lipoprotein is to take this cholesterol from the cells to the liver and it can 169 00:13:19,552 --> 00:13:26,584 along the way clean up the cardiovascular tract preventing plaque buildup and 170 00:13:26,584 --> 00:13:30,218 blockages. See if you go to the doctor, and you may 171 00:13:30,218 --> 00:13:34,953 not only hear a reports of your LDL level, but also the ratio of LDL to HDL. 172 00:13:34,953 --> 00:13:40,060 Improving HDL cholesterol and reducing LDL cholesterol has been shown to be 173 00:13:40,060 --> 00:13:45,007 beneficial in cardiovascular disease. So again let's not blame the lipid 174 00:13:45,007 --> 00:13:49,007 blaming the cholesterol for causing all of these problems. 175 00:13:49,007 --> 00:13:54,307 It's simply the excess intake leading to the excess deposition of the problem. 176 00:13:54,307 --> 00:13:59,657 And you can go to the following link here to see this illustration and learn more 177 00:13:59,657 --> 00:14:03,057 about the progression of cardiovascular disease. 178 00:14:03,057 --> 00:14:07,032 but to give you a basic summary what we're seeing here. 179 00:14:07,032 --> 00:14:12,668 Is that, in this cardiovascular tract in the arteries, we don't have normal blood 180 00:14:12,668 --> 00:14:15,717 flow. And when excess cholesterol and other 181 00:14:15,717 --> 00:14:21,276 components of the blood build up on the arterial walls, it can restrict the blood 182 00:14:21,276 --> 00:14:24,298 flow. When we get the point where this blood 183 00:14:24,298 --> 00:14:29,320 flow is completely restricted or completely blocked, that is when we see 184 00:14:29,320 --> 00:14:31,541 heart attacks. Risk of stroke. 185 00:14:31,541 --> 00:14:36,932 What you eat, how much fat you eat, fiber, how many antioxidants you consume, 186 00:14:36,932 --> 00:14:42,029 how varied your diet is, this can all dictate whether or not you will have more 187 00:14:42,029 --> 00:14:45,149 or less buildup in your cardiovascular system. 188 00:14:45,149 --> 00:14:50,511 Certainly there are genetic components to cholesterol level, and some people can 189 00:14:50,511 --> 00:14:54,332 eat as healthy as ever and still have high cholesterol. 190 00:14:54,332 --> 00:15:00,688 Speaker: But, even if you do have genetic predisposition to high cholesterol, 191 00:15:00,688 --> 00:15:05,124 eating healthy is still key to managing the condition. 192 00:15:05,124 --> 00:15:11,034 So, just in short, we do know that certain foods are going to be better for 193 00:15:11,034 --> 00:15:17,911 maintaining a heart healthy diet, and the Congludo Monounsaturated fatty acids over 194 00:15:17,911 --> 00:15:21,782 saturated ones, improving the Omega-3 intake. 195 00:15:21,782 --> 00:15:25,765 Increasing omega 3s versus all other fatty acids, including Omega-6's 6s. 196 00:15:25,765 --> 00:15:28,892 Consuming more fiber. Talked a little about that in the 197 00:15:28,892 --> 00:15:32,354 carbohydrate lecture. Also, B vitamins to help keep the body 198 00:15:32,354 --> 00:15:34,575 healthy. Antioxidants to help keep the 199 00:15:34,575 --> 00:15:38,657 cardiovascular system strong. And as well as some soy proteins relative 200 00:15:38,657 --> 00:15:41,470 to other proteins. to help balance our body. 201 00:15:41,470 --> 00:15:46,286 We would then like to avoid saturated fats trans fats which are laid to 202 00:15:46,286 --> 00:15:51,668 saturated fats and their effects and excessive cholesterol intake, again you 203 00:15:51,668 --> 00:15:56,459 do use cholesterol all you need cholesterol in your body but your body 204 00:15:56,459 --> 00:16:00,159 meets plenty of it so you don't need to eat it All right. 205 00:16:00,159 --> 00:16:05,830 So I hope you've learned a little bit about fats. 206 00:16:05,830 --> 00:16:10,074 Oops, nope I meant lipids in the diet.