1 00:00:00,012 --> 00:00:04,362 This week, we're going to discuss the macronutrient protein. 2 00:00:04,362 --> 00:00:09,985 When we think about proteins, we can construe those to be the building blocks 3 00:00:09,985 --> 00:00:14,360 of human anatomy. They serve many functions and are crucial 4 00:00:14,360 --> 00:00:19,052 for growth, development, and maintenance of the human being. 5 00:00:19,052 --> 00:00:26,432 When we think about this analogy that we are what we eat, proteins that we eat, 6 00:00:26,432 --> 00:00:33,682 like lipids, become proteins in our body. I've also made an analogy to the idea 7 00:00:33,682 --> 00:00:38,670 that human beings, the body is somewhat like a factory. 8 00:00:39,746 --> 00:00:46,416 We can think about this human factory producing various products and needing 9 00:00:46,416 --> 00:00:53,407 other products to run, to run efficiently and to manufacture what it needs to 10 00:00:53,407 --> 00:00:58,140 manufacture. When you think about calories, proteins 11 00:00:58,140 --> 00:01:04,400 do have calories, calories are fuel. Now remember, carbohydrates are the 12 00:01:04,400 --> 00:01:09,455 preferred fuel source for our bodies. They are what stoke the fire of the 13 00:01:09,455 --> 00:01:11,917 factory. Lipids help run the show. 14 00:01:11,917 --> 00:01:16,975 They make sure everything is running properly, keep things lubricated. 15 00:01:16,975 --> 00:01:21,643 They make sure that products are delivered to the right locations. 16 00:01:21,643 --> 00:01:27,175 They help us synthesize hormones that we need to regulate This mechanism its 17 00:01:27,175 --> 00:01:31,077 factoring. Proteins not only build the factory, but 18 00:01:31,077 --> 00:01:36,739 they're also very important for the running, and the regulating of the human 19 00:01:36,739 --> 00:01:39,952 body. So, we consider these proteins as the 20 00:01:39,952 --> 00:01:45,390 building blocks of the human body, we really need to discuss amino acids. 21 00:01:45,390 --> 00:01:51,762 So truly, if the amino acids that are the blocks of all proteins creating proteins 22 00:01:51,762 --> 00:01:58,007 whether they are, you know, plants, animal or in our own body and tissues. 23 00:01:58,007 --> 00:02:03,652 Let's take a look at amino acids. Amino acids have similar chemical 24 00:02:03,652 --> 00:02:07,297 construct, one difference is the side group. 25 00:02:07,297 --> 00:02:13,277 This is what will really identify a protein, it's what makes a protein one 26 00:02:13,277 --> 00:02:16,580 amino acid. Different from another. 27 00:02:16,580 --> 00:02:22,933 They all have this central carbon. The amino and acid group has amino acid 28 00:02:22,933 --> 00:02:27,887 and a hydrogen. Various amino acids are either essential 29 00:02:27,887 --> 00:02:32,192 or non-essential, depending on that side group. 30 00:02:32,192 --> 00:02:39,541 There are amino acids such as aspartate. So compare that to, for example, alanine. 31 00:02:41,031 --> 00:02:48,290 Phenyalanine, so you can see that these are groups, this side group can be simple 32 00:02:48,290 --> 00:02:52,874 or complex. Here we see one with a ring structure to 33 00:02:52,874 --> 00:02:53,932 it. To it. 34 00:02:53,932 --> 00:03:00,619 Glycine, very simple, just a hydrogen, so you can read in your text book what 35 00:03:00,619 --> 00:03:07,205 specifically which amino acids specifically are essential versus others, 36 00:03:07,205 --> 00:03:13,941 but to just give a better understanding of what this means simply is we can not 37 00:03:13,941 --> 00:03:17,378 synthesise, The non-essential amino acids. 38 00:03:17,378 --> 00:03:22,229 Something about their chemical structure that are a group while we are not 39 00:03:22,229 --> 00:03:26,421 synthesizing that amino acid. Non-essential amino acids can be 40 00:03:26,421 --> 00:03:30,029 synthesized. Now, we do need essential-amino acids in 41 00:03:30,029 --> 00:03:34,759 order to do so but we can actually manufacture certain amino acids in the 42 00:03:34,759 --> 00:03:39,080 body. In this process, we actually break down 43 00:03:39,080 --> 00:03:44,811 the components of another amino acid to make a new amino acid. 44 00:03:44,811 --> 00:03:48,952 So if we take amino acid A off at the top left, 45 00:03:48,952 --> 00:03:54,372 we convert that to amino acid B, down at the bottom right. 46 00:03:54,372 --> 00:04:01,127 We're simultaneously converting a-keto acid, keto acid b to keto acid a. 47 00:04:01,127 --> 00:04:08,247 So look at the chemical structure of a, look at the difference in amino versus 48 00:04:08,247 --> 00:04:12,617 the keto. What's changed? We see that NH2 group. 49 00:04:12,617 --> 00:04:18,922 That amino group is what's changing from a keto acid to amino acid. 50 00:04:18,922 --> 00:04:22,157 Makes sense. So amino acids make protein. 51 00:04:22,157 --> 00:04:27,198 Proteins are one of those complex macro-nutrients structurally. 52 00:04:27,198 --> 00:04:33,077 We have a specific sequence of amino acids that will come together, then fold 53 00:04:33,077 --> 00:04:38,792 in another specific sequence, and then different proteins can actually. 54 00:04:38,792 --> 00:04:41,764 Work together to create a complex protein. 55 00:04:41,764 --> 00:04:46,786 Example of this is haemoglobin. Now, haemoglobin is a complex structure 56 00:04:46,786 --> 00:04:52,010 made of four sub units of protein and you can look that up in your text book as 57 00:04:52,010 --> 00:04:57,702 well, little bit about protein structure. So I'd like you to understand at this 58 00:04:57,702 --> 00:05:02,914 level, is that when we look at a protein whether it be in a food or in a body, the 59 00:05:02,914 --> 00:05:07,481 breakdown of that protein or the denaturazation of that protein does 60 00:05:07,481 --> 00:05:12,814 change its structure and its function. When we denature a protein it's not going 61 00:05:12,814 --> 00:05:17,612 to have the same function. Function for protein is dictated by 62 00:05:17,612 --> 00:05:21,922 structure. Amino acid sequence, folding all these 63 00:05:21,922 --> 00:05:26,497 levels of structure affect how p how protein work. 64 00:05:26,497 --> 00:05:33,072 You can actually see a very easy example of how this is when you go cook a meal 65 00:05:33,072 --> 00:05:37,260 leaving breakfast. Eggs are a great example, not only are 66 00:05:37,260 --> 00:05:42,900 they actually the ideal protein when it comes to the contents of amino acids in 67 00:05:42,900 --> 00:05:48,908 them, we'll talk about that in a moment, but eggs, when cooked, change their form. 68 00:05:48,908 --> 00:05:53,099 So we can have a raw egg. That certainly looks one way or 69 00:05:53,099 --> 00:05:57,907 hard-boiled egg, certainly very different structurally, 70 00:05:57,907 --> 00:06:03,342 texture-wise, consistency. Different from a scrambled egg or poached 71 00:06:03,342 --> 00:06:09,152 egg, different from a quiche or an omelet and different from a whipped egg. 72 00:06:09,152 --> 00:06:13,618 Any two of these processes. Process is whether we boil an egg, 73 00:06:13,618 --> 00:06:18,277 scramble it, fry it or whip it, we are denaturing the protein. 74 00:06:18,277 --> 00:06:20,359 In. the digestion lecture. 75 00:06:20,359 --> 00:06:24,196 you actually learned how proteins are broken down. 76 00:06:24,196 --> 00:06:27,109 and thus. in the human body denatured. 77 00:06:27,109 --> 00:06:32,801 The structure and function that the protein had in your food, whether it be, 78 00:06:32,801 --> 00:06:38,838 in the egg, or amino acids in a plant, or amino acids in chicken They serve some 79 00:06:38,838 --> 00:06:42,424 function in the chicken and the planter and the egg. 80 00:06:42,424 --> 00:06:47,319 They could potentially serve very different function in your body once 81 00:06:47,319 --> 00:06:52,416 those amino acids are taken apart, put back together, into a new protein. 82 00:06:52,416 --> 00:06:57,952 The other important factor nutritionally when we talk about proteins is protein 83 00:06:57,952 --> 00:07:01,635 digestibility. When it comes to protein digestibility 84 00:07:01,635 --> 00:07:04,512 the type of protein is going to be important. 85 00:07:04,512 --> 00:07:09,598 Not just whether it be proteins or amino acid that came from meat versus plants, 86 00:07:09,598 --> 00:07:13,515 but different meats have different levels of digestibility. 87 00:07:13,515 --> 00:07:18,384 Protein digestibility is not just important when it comes to breaking down, 88 00:07:18,384 --> 00:07:23,541 obtaining the nutrition and amino acids we need from the meat itself, or the food 89 00:07:23,541 --> 00:07:26,968 itself. But also all the nutrients that are 90 00:07:26,968 --> 00:07:32,544 compounded in that protein matrix. Later we'll talk a little bit about 91 00:07:32,544 --> 00:07:37,269 vitamins and minerals. One vitamin that is very affected by 92 00:07:37,269 --> 00:07:42,578 protein digestibility is B12. As we get older our ability to digest 93 00:07:42,578 --> 00:07:45,871 food decreases. This includes proteins. 94 00:07:45,871 --> 00:07:51,839 So you might have two meal options to get B12 and protein, of course, perhaps a 95 00:07:51,839 --> 00:07:56,386 steak or chicken. Now though the chicken has less vitamin 96 00:07:56,386 --> 00:08:02,596 B12 in it, compared to the beef, the chicken's vitamin B12 is more digestible, 97 00:08:02,596 --> 00:08:06,230 because the chicken itself is more digestible than beef. 98 00:08:07,306 --> 00:08:13,269 When macro-nutrients bind micro-nutrients so when a protein finds certain minerals 99 00:08:13,269 --> 00:08:17,045 or vitamins. If we can't digest the protein, we can't 100 00:08:17,045 --> 00:08:21,522 create a vitamin and will not absorb or utilize that vitamin. 101 00:08:21,522 --> 00:08:24,692 So we talk a little bit about protein nutrition. 102 00:08:24,692 --> 00:08:29,835 When you read about protein nutrition you think about protein sources and what 103 00:08:29,835 --> 00:08:34,052 other vitamins they might supply or minerals they might supply. 104 00:08:34,052 --> 00:08:39,197 Keep in mind that the mineral or vitamin content of any given protein is only as 105 00:08:39,197 --> 00:08:43,936 good as its digestibility. This also, of course, is going to apply 106 00:08:43,936 --> 00:08:50,186 to amino acids, so when we think about how good a protein might be or protein 107 00:08:50,186 --> 00:08:53,389 quality. So when we think nutritionally about 108 00:08:53,389 --> 00:08:58,794 protein, digestibility is going to be very important, not only when it come to 109 00:08:58,794 --> 00:09:04,432 bringing amino acids, and gaining these essential or nonessential amino acids in 110 00:09:04,432 --> 00:09:11,027 our diet, but also green based vitamins, such as B12 as the example I gave. 111 00:09:11,027 --> 00:09:17,527 So now, we think about amino acid content, and digestibility, we can talk 112 00:09:17,527 --> 00:09:22,702 about protein quality. Now in the simplest terms, protein 113 00:09:22,702 --> 00:09:28,203 quality is simply about the essential amino acid content. A complete protein 114 00:09:28,203 --> 00:09:32,585 will have the perfect ratio of amino acids needed for human growth, 115 00:09:32,585 --> 00:09:37,155 development and maintenance. Incomplete proteins are the one that one 116 00:09:37,155 --> 00:09:41,584 or more special amino acids and these are typically plant proteins. 117 00:09:41,584 --> 00:09:44,530 Animal based proteins are typically complete. 118 00:09:45,653 --> 00:09:51,350 Whatever amino acid is present in lowest amounts will be considered the limiting 119 00:09:51,350 --> 00:09:55,259 amino acids. They will limit the protein's capacity to 120 00:09:55,259 --> 00:09:59,954 synthesize body protein. Now, if you live in a situation where you 121 00:09:59,954 --> 00:10:05,539 only have one food stuff, and it is plant based, you might see imbalances in amino 122 00:10:05,539 --> 00:10:11,895 acid availability and protein synthesis. But if you have some variation to your 123 00:10:11,895 --> 00:10:16,416 diet, even if you have access to just rice and beans, you will get all the 124 00:10:16,416 --> 00:10:20,630 amino acids that you need. If you're a vegetarian you may have heard 125 00:10:20,630 --> 00:10:25,396 of terms such as complementary protein, combining foods to get all the amino 126 00:10:25,396 --> 00:10:28,268 acid. And while getting all the amino acids is 127 00:10:28,268 --> 00:10:32,069 very important It's not a matter of getting it in the same meal. 128 00:10:32,069 --> 00:10:36,513 If you get all of the amino acids that you need on a regular basis, even if it's 129 00:10:36,513 --> 00:10:41,058 a daily basis, you can say something as specific as a daily basis, you will have 130 00:10:41,058 --> 00:10:45,125 the proteins, you will have the amino acids that you need to synthesize 131 00:10:45,125 --> 00:10:48,112 protein. So we have the egg as our example 132 00:10:48,112 --> 00:10:51,427 protein. These are the, this is the amino acid 133 00:10:51,427 --> 00:10:55,222 content of an egg. The essential amino acid content. 134 00:10:55,222 --> 00:11:00,452 And we can compare this ratio to other proteins to determine its quality. 135 00:11:00,452 --> 00:11:05,822 There are now different analytical and laboratory methods for determining 136 00:11:05,822 --> 00:11:10,277 protein quality. We can consider the chemical score. 137 00:11:10,277 --> 00:11:16,030 This is the most basic analysis. This will compare the essential amino 138 00:11:16,030 --> 00:11:22,293 acid content of any given protein, so perhaps some chicken, to the numerical 139 00:11:22,293 --> 00:11:26,142 score generated from the ratio found in an egg. 140 00:11:26,142 --> 00:11:30,167 Now chemical score does not consider digestability. 141 00:11:30,167 --> 00:11:34,922 We can also measure protein quality through biological value. 142 00:11:34,922 --> 00:11:41,427 Biological value's determined by nitrogen retention in animals that attest protein. 143 00:11:41,427 --> 00:11:44,942 A biological value over 70% supports human growth. 144 00:11:44,942 --> 00:11:50,057 We can also measure protein quality by protein efficiency ratio. 145 00:11:50,057 --> 00:11:56,089 This measures weight gain in animals fed a test protein, and it is the measure 146 00:11:56,089 --> 00:12:01,116 used for protein comparisons of infant formulas and baby foods. 147 00:12:01,116 --> 00:12:06,583 Finally we have the protein digestiblity corrected amino acid score. 148 00:12:06,583 --> 00:12:10,462 This measures essential amino acid composition. 149 00:12:10,462 --> 00:12:14,787 Compared to needs, with an adjustment, for digestibility. 150 00:12:14,787 --> 00:12:19,617 This measure, is what is used, to determine, percent daily value. 151 00:12:19,617 --> 00:12:23,213 That's the number you see on all your food labels. 152 00:12:23,213 --> 00:12:27,223 This, we are going to explore, some more in a few moments. 153 00:12:27,223 --> 00:12:29,758 Alright. So let's first look at amino acid's 154 00:12:29,758 --> 00:12:32,079 score. On the left you can see a list of 155 00:12:32,079 --> 00:12:36,785 essential amino acids, followed by a column with our reference protein and our 156 00:12:36,785 --> 00:12:41,095 test protein, which is beans. These amino acids are given in milligrams 157 00:12:41,095 --> 00:12:46,006 of amino acids, program protein So in this case what's our limiting amino 158 00:12:46,006 --> 00:12:48,890 acids. As we go down the list we say most of 159 00:12:48,890 --> 00:12:51,902 these amino acids actually scored over one. 160 00:12:51,902 --> 00:12:56,989 Our limiting amino acid is lysine. It's less than one so therefore it would 161 00:12:56,989 --> 00:13:00,372 be the missing essential amino acid in this food. 162 00:13:00,372 --> 00:13:03,734 Food. We can compare different scores of 163 00:13:03,734 --> 00:13:10,197 different foods, so again, this is our Protein Digestibility Corrected Amino 164 00:13:10,197 --> 00:13:14,285 Acid Score. Casein, eggs, and other animal based 165 00:13:14,285 --> 00:13:20,631 foods are going to have a score of 1. Soy beans actually that make tofu and 166 00:13:20,631 --> 00:13:25,224 tempe are very high for plants, .99, it's almost 1. 167 00:13:25,224 --> 00:13:31,979 Beef is lower, so why is that? Well, there is an adjustment for digestibility. 168 00:13:31,979 --> 00:13:38,465 Beef, as I mentioned a little earlier, has a lower digestibility than other 169 00:13:38,465 --> 00:13:41,968 meat. So even though it is a complete protein, 170 00:13:41,968 --> 00:13:46,732 so if we looked at potentially its chemical score, it would get a high 171 00:13:46,732 --> 00:13:50,422 chemical score. The digestibility in beef lowers its 172 00:13:50,422 --> 00:13:55,213 digestibility corrected score. As you look further down, you see the 173 00:13:55,213 --> 00:13:58,978 numbers drop. Whole wheat bread, for example, has the 174 00:13:58,978 --> 00:14:02,858 lowest Protein score. So let's see how this, these numbers 175 00:14:02,858 --> 00:14:06,374 actually add up. So with the beef equation there you might 176 00:14:06,374 --> 00:14:08,944 have expected beef to have a higher score. 177 00:14:08,944 --> 00:14:12,611 Let's consider peanuts. There's the equation for the actual 178 00:14:12,611 --> 00:14:15,499 score. We can see that the amino acid score that 179 00:14:15,499 --> 00:14:20,342 I mentioned earlier, that's actually comparing our test protein, peanuts. 180 00:14:20,342 --> 00:14:25,747 To an example protein, the egg. We'll then multiply that by its 181 00:14:25,747 --> 00:14:30,001 digestibility. We take the amino acid score from the 182 00:14:30,001 --> 00:14:35,463 profiled amino acids by measuring the lowest amino acid available. 183 00:14:35,463 --> 00:14:40,542 So the score is going to be coming from the lowest amino acid. 184 00:14:40,542 --> 00:14:45,702 In the case of peanuts the lowest amino acid score .49. 185 00:14:45,702 --> 00:14:50,596 So 94% digestible so we'll multiply this times .94. 186 00:14:50,596 --> 00:14:55,997 Then our final score is .46. This is not 100% digestible. 187 00:14:55,997 --> 00:15:00,707 We've lowered the score relative to its lowest amino acid. 188 00:15:00,707 --> 00:15:05,242 So how do we compare this to the daily value if I buy a bag of peanuts and I 189 00:15:05,242 --> 00:15:10,057 look at the label? How do I know where this daily value came from? Well now we 190 00:15:10,057 --> 00:15:14,397 can see percent daily value by knowing our own given daily value, the 191 00:15:14,397 --> 00:15:17,982 established recommendation, and comparing that to... 192 00:15:17,982 --> 00:15:23,267 The score so now we can divide the score, that final score that we get, times the 193 00:15:23,267 --> 00:15:27,860 amount of protein per serving. Again when we look at daily values of a 194 00:15:27,860 --> 00:15:32,823 food label they're given in servings. And divide by the daily value, again 195 00:15:32,823 --> 00:15:37,192 amount of protein times the score, divided by the daily value. 196 00:15:37,192 --> 00:15:43,260 So, let's say we had 7 grams of protein in our sample of peanuts. 197 00:15:43,260 --> 00:15:48,951 The score was 0.46, and the daily value is 50 grams protein. 198 00:15:48,951 --> 00:15:55,492 So, this amount of peanuts provides us with 6.4% of our daily value. 199 00:15:55,492 --> 00:15:59,922 Of protein. Considering the amount of protein in the 200 00:15:59,922 --> 00:16:04,232 food and its amino acid content and digestibility. 201 00:16:04,232 --> 00:16:10,637 Alright now lets compare peanuts to another protein, something that is very 202 00:16:10,637 --> 00:16:14,692 digestible and has a solid amino acid profile. 203 00:16:14,692 --> 00:16:19,962 Yoghurt is a great example. It's a healthy food and it is a complete 204 00:16:19,962 --> 00:16:21,892 protein. It scores one. 205 00:16:21,892 --> 00:16:26,286 Highly digestible, gets us all the amino acids we need. 206 00:16:26,286 --> 00:16:31,111 It provides, in a serving, 10% of our daily value of protein. 207 00:16:31,111 --> 00:16:36,597 Now if we look at the amount of protein per Food, 5 g of protein in yoghurt 208 00:16:36,597 --> 00:16:41,604 versus 7 g of protein in peanuts, we think hm, peanuts will give me more 209 00:16:41,604 --> 00:16:43,413 protein. I need protein, 210 00:16:43,413 --> 00:16:48,374 I should eat peanuts instead. But when you consider digestibility and 211 00:16:48,374 --> 00:16:53,518 the amino acid profile, you see that peanuts actually provide less amino 212 00:16:53,518 --> 00:16:57,412 acids, less of a daily value of proteins than yoghurt. 213 00:16:57,412 --> 00:17:02,036 Certainly, you can have some peanuts with your yogurt, but if you're going to 214 00:17:02,036 --> 00:17:06,899 choose one over the other, the yogurt is the more complete protein providing more 215 00:17:06,899 --> 00:17:11,869 amino acids, especially essential amino acids, when we're choosing between one or 216 00:17:11,869 --> 00:17:14,718 the other. So I alluded to before the concept of 217 00:17:14,718 --> 00:17:18,992 vegetarianism, and combining foods to have complimentary protein. 218 00:17:18,992 --> 00:17:23,940 So regardless of where your beef is, in the field or on your plate, you can eat 219 00:17:23,940 --> 00:17:26,859 healthy. There's certainly numerous healthy 220 00:17:26,859 --> 00:17:32,133 benefits to becoming a Vegetarian, or to simply eating a higher plant-based diet. 221 00:17:32,133 --> 00:17:35,532 Plants, fruits and vegetables, are higher in fiber. 222 00:17:35,532 --> 00:17:40,402 They come with a significant amount of essential vitamins and minerals. 223 00:17:40,402 --> 00:17:44,171 They're lower in fats particularly saturated fat. 224 00:17:44,171 --> 00:17:49,900 And while meat can be a very good part of a balanced diet it does not have to be. 225 00:17:49,900 --> 00:17:55,753 And again reminding you, too, that this idea of complimentary proteins, while 226 00:17:55,753 --> 00:18:01,352 certainly it is important that you eat a very Level of protein in your diet, you 227 00:18:01,352 --> 00:18:06,702 eat different fruits, nuts, and seeds, beans, legumes, vegetables, whole grains. 228 00:18:06,702 --> 00:18:11,162 It doesn't mean that you have to eat every single one of these, at every 229 00:18:11,162 --> 00:18:14,262 single meal, to get the amino acid that you need. 230 00:18:14,262 --> 00:18:19,002 When it comes to proteins and amino acids, it's the amino acids full in your 231 00:18:19,002 --> 00:18:22,372 body that's important not just the stomach content. 232 00:18:22,372 --> 00:18:30,857 This amino acid pool is where we get, what we need to make proteins. 233 00:18:30,857 --> 00:18:37,778 Body proteins, new amino acids. To even generate glucose, glycogen and 234 00:18:37,778 --> 00:18:42,082 lipids, we'll talk more about that in the metabolism section. 235 00:18:42,082 --> 00:18:47,002 To make non-protein compounds that do require amino acids or nitrogen. 236 00:18:47,002 --> 00:18:52,226 And then, of course, some of the amino acids from the amino acid pool will be 237 00:18:52,226 --> 00:18:56,547 broken down and excreted. This pool When kept constant will always 238 00:18:56,547 --> 00:18:59,047 supply the body with amino acids it needs. 239 00:18:59,047 --> 00:19:03,422 So again, as long as you eat what you need to during the day, it will supply 240 00:19:03,422 --> 00:19:07,527 the amino acid pool and you will be able to make the proteins you need. 241 00:19:07,527 --> 00:19:11,172 Now, individuals really interested in protein generation. 242 00:19:11,172 --> 00:19:15,476 Body builders, for example, that want to build large amounts of muscle mass. 243 00:19:15,476 --> 00:19:19,497 Or individuals recovering from significant illness or a burn may want to 244 00:19:19,497 --> 00:19:23,615 make sure that they're constantly refreshing this amino acid pool through 245 00:19:23,615 --> 00:19:26,197 the diet. Why is that? Well if you need to draw 246 00:19:26,197 --> 00:19:29,023 more and more out, look at the way these arrows go. 247 00:19:29,023 --> 00:19:33,612 You are going to get amino acids from the breakdown of body proteins if necessary. 248 00:19:33,612 --> 00:19:38,183 So, if you're trying to minimize body protein utilizations, you make amino 249 00:19:38,183 --> 00:19:42,963 acids for this amino acid pool, or to break them down, eating more protein will 250 00:19:42,963 --> 00:19:45,968 be protective. So, if you are a weight lifter, or 251 00:19:45,968 --> 00:19:50,246 someone in hospital or you're treating someone in a hospital that has a 252 00:19:50,246 --> 00:19:55,152 significant amount of tissue loss, making sure they get proteins through out the 253 00:19:55,152 --> 00:19:59,532 day And really the amino acids you are looking for them to get, making sure they 254 00:19:59,532 --> 00:20:03,592 get these amino acids throughout the day to keep, and you can even see some 255 00:20:03,592 --> 00:20:07,927 individuals in the extreme of this that will eat every two hours even during the 256 00:20:07,927 --> 00:20:12,507 night to make sure they are constantly bringing in new fresh Amino acid. 257 00:20:12,507 --> 00:20:17,570 Now if we simplify this concept of amino acid pool. 258 00:20:17,570 --> 00:20:24,721 We can break it down all the way to the nitrogen that's in the amino acid. 259 00:20:24,721 --> 00:20:31,737 Nitrogen is what sets amino acids and proteins apart from the other Core 260 00:20:31,737 --> 00:20:34,692 nutrients. Carbs and fat don't have nitrogen. 261 00:20:34,692 --> 00:20:39,502 When we look at protein balance, and when I consider the protein status of an 262 00:20:39,502 --> 00:20:43,182 individual, we can actually talk about nitrogen balance. 263 00:20:43,182 --> 00:20:46,587 And you can read a little more about this in your text. 264 00:20:46,587 --> 00:20:51,447 But to just give you a basic idea of what's happening, when we look at stasis, 265 00:20:51,447 --> 00:20:54,822 or the even state, we'll be in nitrogen balance. 266 00:20:54,822 --> 00:20:59,957 If we're eating more protein than we're excreting, we'll be in positive balance. 267 00:20:59,957 --> 00:21:04,672 If we're excreting more protein, than we'e taking in, we'll be in negative 268 00:21:04,672 --> 00:21:07,537 balance . So a healthy adult, for example not 269 00:21:07,537 --> 00:21:10,422 growing any more, they'll be in equilibrium. 270 00:21:10,422 --> 00:21:14,422 They'll be in balance. Someone who is growing is going to be in 271 00:21:14,422 --> 00:21:19,197 positive nitrogen balance. In pregnancy, you're in positive nitrogen 272 00:21:19,197 --> 00:21:24,447 balance, as well as when recovering from illness, particularly in a burn type 273 00:21:24,447 --> 00:21:29,397 situation, or any illness where significant tissue damage has occurred, 274 00:21:29,397 --> 00:21:31,997 and significant tissue synthesis must happen to you. 275 00:21:33,654 --> 00:21:37,985 Negative nitrogen balance is when we're losing more nitrogen. 276 00:21:37,985 --> 00:21:43,388 So before we get to the recovery stages of an illness, for example, we may be in 277 00:21:43,388 --> 00:21:48,077 negative nitrogen balance. So that burn victim in this early stages 278 00:21:48,077 --> 00:21:51,894 of synthesis is going to still be losing more dead tissue. 279 00:21:51,894 --> 00:21:54,845 That dead tissue's. It's going to break down. 280 00:21:54,845 --> 00:21:59,213 We're going to break down the amino acids in that tissue, the nitrogen in that 281 00:21:59,213 --> 00:22:01,918 tissue. And continue to lose more nitrogen than 282 00:22:01,918 --> 00:22:05,120 we are taking in. So, in certain situations we do want to 283 00:22:05,120 --> 00:22:09,413 make sure we're eating more protein so that we're supplying more nitrogen to 284 00:22:09,413 --> 00:22:11,128 help the healing of. Occur. 285 00:22:11,128 --> 00:22:16,366 So you will see, a dietician, for example, considering protein more, in 286 00:22:16,366 --> 00:22:20,289 certain individuals, that do need more nitrogen to heal. 287 00:22:20,289 --> 00:22:24,211 Alright, so we know a little about proteins, in the diet. 288 00:22:24,211 --> 00:22:28,311 What proteins are doing, how the amino acids are important. 289 00:22:28,311 --> 00:22:32,233 But what, do proteins do? Okay, they build body tissues. 290 00:22:32,233 --> 00:22:35,244 Hair, nails, skin, those are all proteins. 291 00:22:35,244 --> 00:22:39,612 But proteins do other things, than just making body protein. 292 00:22:39,612 --> 00:22:44,500 They're very important for all of our tissues, bones, teeth, collagen, muscle 293 00:22:44,500 --> 00:22:47,445 fibers. But they're also important on their own 294 00:22:47,445 --> 00:22:50,483 not just part of a muscle matrix as transporters. 295 00:22:50,483 --> 00:22:54,752 Our proteins are our transporters. We talked in lipids about the cell 296 00:22:54,752 --> 00:22:58,755 membrane and the importance of lipids for a healthy cell membrane. 297 00:23:00,022 --> 00:23:04,592 Well proteins are also very important there. 298 00:23:04,592 --> 00:23:11,752 They'll actually be the pumps. They'll be the vessels, the streets, if 299 00:23:11,752 --> 00:23:17,877 you will, the pathways from one side of the cell to the other. 300 00:23:17,877 --> 00:23:26,427 We can see various types, of, proteins. Pushing, components from one cell, side 301 00:23:26,427 --> 00:23:31,809 of the cell to the other. What's most important here is it's the 302 00:23:31,809 --> 00:23:37,642 protein that are these transporters. Insulin for example, the insulin receptor 303 00:23:37,642 --> 00:23:43,338 and the insulin transporters are protein. So taking that example, the protein 304 00:23:43,338 --> 00:23:48,548 function in diabetes or in blood sugar control, so the pancreas is going to 305 00:23:48,548 --> 00:23:53,596 generate the insulin in response to blood sugar going up after we eat a 306 00:23:53,596 --> 00:23:57,591 carbohydrate. And insulin is actually going to signal 307 00:23:57,591 --> 00:24:02,880 transporters to go to the cell wall, become available to pick up glucose and 308 00:24:02,880 --> 00:24:07,726 draw the glucose into the cell. Once in the cell, blood sugar lowers. 309 00:24:07,726 --> 00:24:12,266 Without protein and protein insufficiency, we can't continue to 310 00:24:12,266 --> 00:24:17,092 generate those transporters in cells and we can impair this process. 311 00:24:17,092 --> 00:24:22,392 So protein deficiencies affect our transportation, which can effect delivery 312 00:24:22,392 --> 00:24:26,217 of numerous things from one place in the body to another. 313 00:24:26,217 --> 00:24:31,242 Proteins are also very important in maintaining water in right locations. 314 00:24:31,242 --> 00:24:36,092 We'll talk a little bit more about that when we talk about electrolytes. 315 00:24:36,092 --> 00:24:41,761 But along with electroytes, protiens are very important with attracting water Into 316 00:24:41,761 --> 00:24:46,822 the cardiovascular system and keeping water where it should be, in the veins an 317 00:24:46,822 --> 00:24:49,482 arteries. Someone that does have protein 318 00:24:49,482 --> 00:24:54,184 insufficiency may develop edema. Edema is simply when water that's meant 319 00:24:54,184 --> 00:24:59,128 to be in the vessels leaks out of these vessels and enters the body tissues and 320 00:24:59,128 --> 00:25:03,055 we see swelling. And the swelling, specificically edema is 321 00:25:03,055 --> 00:25:08,590 due to low protein, not keeping water, in the vac, cardiovascular system allowing 322 00:25:08,590 --> 00:25:11,212 it to build up in those tissues and swell. 323 00:25:12,296 --> 00:25:17,366 Proteins are also very important buffers. They can actually donate or accept 324 00:25:17,366 --> 00:25:20,730 electrons to help maintain that acid base balance. 325 00:25:20,730 --> 00:25:25,729 The lower the number the more acidic. The higher the number the more basic it 326 00:25:25,729 --> 00:25:28,878 is. And so proteins along, and again we'll 327 00:25:28,878 --> 00:25:33,386 talk about, with electrolytes are very important, buffers. 328 00:25:33,386 --> 00:25:38,724 Protein is also important in glucose production and energy production. 329 00:25:38,724 --> 00:25:44,726 Certain amino-acids, termed glucogenic amino-acids, are converted to pyruvate 330 00:25:44,726 --> 00:25:49,602 when broken down, heated and can then be converted to glucose. 331 00:25:49,602 --> 00:25:53,477 We'll talk a little bit more about this we get to metabolism. 332 00:25:53,477 --> 00:25:58,751 Other amino acids, termed [UNKNOWN] are converted to Acetyl CoA when broken down, 333 00:25:58,751 --> 00:26:03,690 and so they are not going to be able to be utilized in generating Glucose. 334 00:26:03,690 --> 00:26:08,854 Protein deficiency is a significant problems across the globe. 335 00:26:08,854 --> 00:26:15,674 Certainly, here, in the modern world, we have both protein excess, calorie excess, 336 00:26:15,674 --> 00:26:20,888 malnutrition of all kind. But protein deficiency has long been a 337 00:26:20,888 --> 00:26:27,474 concern for global assistance groups. Encroaching defficiency, we can see the 338 00:26:27,474 --> 00:26:33,516 classical images of a child looking emaciated still somehow have that swollen 339 00:26:33,516 --> 00:26:37,532 belly and feet, swollen arms, swollen hands. 340 00:26:37,532 --> 00:26:42,973 This is a [UNKNOWN] So remember we said that proteins are very important at 341 00:26:42,973 --> 00:26:47,279 keeping water where it belongs in the cardiovascular system. 342 00:26:47,279 --> 00:26:51,142 When we don't have enough protein this water leaks out. 343 00:26:51,142 --> 00:26:55,264 When we don't have enough calories, child will not thrive. 344 00:26:55,264 --> 00:27:00,110 So here we see example, of not just failure to thrive, but protein and 345 00:27:00,110 --> 00:27:04,177 calorie insufficiency. If we are getting enough protein, and 346 00:27:04,177 --> 00:27:08,737 we're just not getting enough calories, we won't see any edema in that child. 347 00:27:08,737 --> 00:27:13,337 That's a little bit about protein, so don't forget you should be reading these 348 00:27:13,337 --> 00:27:17,342 chapters before you listen to my lectures, so these lectures should 349 00:27:17,342 --> 00:27:21,465 certainly be building on what you've read and help tie things together.