1 00:00:00,012 --> 00:00:04,313 A growing number of countries are developing and revising their dietary 2 00:00:04,313 --> 00:00:07,285 guidelines, and food guide education materials. 3 00:00:07,285 --> 00:00:12,016 We can think about our dietary guidelines in 2 major categories, Food-based and 4 00:00:12,016 --> 00:00:15,120 Biochemical. Food-based guidelines talk about what 5 00:00:15,120 --> 00:00:19,496 foods we need to eat to meet our nutritional needs, while the Biochemical 6 00:00:19,496 --> 00:00:22,992 guidelines define a nutrient and nutrient requirement. 7 00:00:22,992 --> 00:00:27,765 Both are estimations, and typically generalized to a population with some 8 00:00:27,765 --> 00:00:32,229 consideration of age and gender. Dietary guidelines are derived from 9 00:00:32,229 --> 00:00:36,217 research that's determining the nutritional needs of humans. 10 00:00:36,217 --> 00:00:41,604 In determining biological requirements, we've also developed clinical measures of 11 00:00:41,604 --> 00:00:46,209 status that can be used in medical and nutritional assessment. 12 00:00:46,209 --> 00:00:51,745 Health care experts can then use these assessments to help prevent malnutrition 13 00:00:51,745 --> 00:00:55,614 and disease. The guidelines, especially the food based 14 00:00:55,614 --> 00:01:01,150 guidelines, are designed to inform the public about nutritional requirements. 15 00:01:01,150 --> 00:01:06,607 In addition, they give information on nutrient content of foods, and are based 16 00:01:06,607 --> 00:01:12,257 on population based measures. Countries having their own guidelines 17 00:01:12,257 --> 00:01:17,416 face among many factors including scientific research, cultural and dietary 18 00:01:17,416 --> 00:01:22,624 habits and agricultural industries. Since different cultures have different 19 00:01:22,624 --> 00:01:26,692 food availabilities, food preferences, dietary patterns. 20 00:01:26,692 --> 00:01:32,482 In cultural definitions of foods, it's clear a global food guidance system would 21 00:01:32,482 --> 00:01:36,437 be inappropriate. In this lesson, you'll get a chance to 22 00:01:36,437 --> 00:01:41,827 look up the dietary guidelines in your country, and share and contrast this 23 00:01:41,827 --> 00:01:46,806 information with other students. To give you background and a starting 24 00:01:46,806 --> 00:01:51,764 point, let's consider the development of the dietary guidelines in the US. 25 00:01:51,764 --> 00:01:57,010 The US food guide system is based on the United States of Agriculture's research 26 00:01:57,010 --> 00:02:02,353 on the types of foods Americans consume, the nutrient composition of these foods 27 00:02:02,353 --> 00:02:07,135 and the relation to the individual's nutrient needs. 28 00:02:07,135 --> 00:02:13,585 So let's see how it's changed over time. We'll start in 1894. 29 00:02:13,585 --> 00:02:21,621 Here we can see somewhat of a generic message looking mainly at the American 30 00:02:21,621 --> 00:02:26,385 male. The next message looks a little more at 31 00:02:26,385 --> 00:02:36,536 keeping someone fit. Then we see the start of a number of food 32 00:02:36,536 --> 00:02:48,942 groups, numbering them. Simplifying that number a little bit. 33 00:02:48,942 --> 00:03:00,796 Making things even simpler by putting hassle-free in the title. 34 00:03:00,796 --> 00:03:09,300 And in 1980, we saw the first. Example of the dietary guidelines for 35 00:03:09,300 --> 00:03:13,491 Americans. And this is going to be revised every 5 36 00:03:13,491 --> 00:03:17,161 years. so you will see how that changes too. 37 00:03:18,583 --> 00:03:24,092 We see some reference to give you that we eat in some type of pattern. 38 00:03:24,092 --> 00:03:31,457 And then we start to see these examples that show a pictorial image that's 39 00:03:31,457 --> 00:03:38,782 supposed to guide us on how to eat. And here we have the good guide pyramid 40 00:03:38,782 --> 00:03:44,257 that started. That pyramid was changed a bit to make it 41 00:03:44,257 --> 00:03:49,389 more personable. And then we've gone back to an image that 42 00:03:49,389 --> 00:03:55,736 everyone can recognize, the thing that you eat off of, whether it be paper or 43 00:03:55,736 --> 00:03:59,477 plastic, ceramic or even a piece of bread, MyPlate. 44 00:04:00,924 --> 00:04:08,972 So what does this look like in pictures? we have the details of the groups here. 45 00:04:08,972 --> 00:04:15,427 Let's see what type of images were sent out to educate the public. 46 00:04:15,427 --> 00:04:20,822 So here we have that generic making us healthy example. 47 00:04:20,822 --> 00:04:25,760 If you notice, you'll show here pictures, of how much food someone should eat. 48 00:04:25,760 --> 00:04:30,630 So, if you couldn't read for example, you might try to get an understanding of, 49 00:04:30,630 --> 00:04:35,203 well that's what my food should look like, for an average family in a week. 50 00:04:35,203 --> 00:04:39,937 We even see pictures of happy children eating, so, if you eat well you will be 51 00:04:39,937 --> 00:04:44,867 happy, might have been the message they were trying Trying to convey. 52 00:04:44,867 --> 00:04:51,378 As we go on we now see groupings of foods before everything was put together. 53 00:04:51,378 --> 00:04:55,962 Here we see foods broken up into different sections. 54 00:04:55,962 --> 00:05:05,304 Again, different sections and through nutrition research and understanding we 55 00:05:05,304 --> 00:05:12,782 did, at different times, group different types of foods together. 56 00:05:12,782 --> 00:05:20,822 As we went on, we saw simplification of the message. 57 00:05:20,822 --> 00:05:27,392 Here are only 4 food groups are appearing. 58 00:05:27,392 --> 00:05:38,505 Continuing again this idea of the hassle-free guide, this is an older 59 00:05:38,505 --> 00:05:46,142 document, so it may get a little harder to read. 60 00:05:46,142 --> 00:05:52,172 But we do see a vegetable and fruit group, a bread and cereal group, a milk 61 00:05:52,172 --> 00:05:57,714 and cheese group and then the meat and poultry, fish and bean group. 62 00:05:57,714 --> 00:06:03,939 As I mentioned, we then went to the idea of providing dietary guidelines for 63 00:06:03,939 --> 00:06:10,606 Americans actually manuscripts giving more information, detailed education on 64 00:06:10,606 --> 00:06:17,169 what we should eat. And again this is still based on 65 00:06:17,169 --> 00:06:24,449 research. Continuing on with the Food Guidance 66 00:06:24,449 --> 00:06:34,407 System, we saw a change in the shape so it's not just blocks of food, now we saw 67 00:06:34,407 --> 00:06:37,377 some creativity coming in here, trying to make a Food wheel. 68 00:06:37,377 --> 00:06:47,842 And then there's that Food Pyramid that started in 92'. 69 00:06:47,842 --> 00:06:55,149 This was changed in 2005, and what you can see that's different here, is now 70 00:06:55,149 --> 00:07:02,678 there's a person in it, so we considered that maybe we needed to make this more 71 00:07:02,678 --> 00:07:10,402 individual, and also by having the person on the stairs, we see that activities 72 00:07:10,402 --> 00:07:15,185 brought into play. Still people were challenged by 73 00:07:15,185 --> 00:07:20,417 understanding how much they should eat, quantity wise. 74 00:07:20,417 --> 00:07:25,830 So then we come to MyPlate, a more straightforward image. 75 00:07:25,830 --> 00:07:32,622 Something you'd definitely recognise. It's a plate And as a nutrition educator 76 00:07:32,622 --> 00:07:37,947 I like that the dairy is a round circle. To me that guides someone to think about 77 00:07:37,947 --> 00:07:43,147 dairy as milk or yogurt, not just cheese which typically comes with more fat. 78 00:07:43,147 --> 00:07:46,297 Which is now considered to be excess calories. 79 00:07:46,297 --> 00:07:51,647 In addition to the food based guidelines research has also helped us understand 80 00:07:51,647 --> 00:07:55,492 nutritional requirements on the biochemical level. 81 00:07:55,492 --> 00:08:00,734 Measuring nutritional status either directly or indirectly within a study 82 00:08:00,734 --> 00:08:06,210 population, and expanding scientific findings to make intake recommendation 83 00:08:06,210 --> 00:08:10,722 based on age and gender. These dietary reference intakes tell us 84 00:08:10,722 --> 00:08:16,323 just how much carbohydrates, lipids, protein, vitamins and minerals we need to 85 00:08:16,323 --> 00:08:21,172 reach biological sufficiency. Keep in mind, recommendations are 86 00:08:21,172 --> 00:08:26,112 population based and each individual may actually need more or less. 87 00:08:26,112 --> 00:08:31,587 The recommendations are set to meet nutrient requirements, prevent disease 88 00:08:31,587 --> 00:08:37,427 and deficiency and avoid excess intake. So they may not be perfect for everybody, 89 00:08:37,427 --> 00:08:42,752 but we can use them to understand how we get these vitamins out of our food. 90 00:08:42,752 --> 00:08:47,352 Food and how much we need. Since dietary reference intakes are based 91 00:08:47,352 --> 00:08:52,552 primarily on deficiency we should first consider how nutritional deficiency 92 00:08:52,552 --> 00:08:56,502 develops and how we can evaluate status at various stages. 93 00:08:56,502 --> 00:09:01,852 For vitamin and mineral requirements the laboratory tests will give us the best 94 00:09:01,852 --> 00:09:07,315 model for determining Requirement. Once we have a biological graph print, we 95 00:09:07,315 --> 00:09:12,866 can scientifically determine the level of intake needed to obtain a given blood 96 00:09:12,866 --> 00:09:18,492 value, and in some cases, we may measure actual plasma or serum concentrations, 97 00:09:18,492 --> 00:09:21,915 and other cases we may measure enzyme activitiy. 98 00:09:21,915 --> 00:09:28,944 We can see here the stages of deveolpment In the assessment methods. 99 00:09:28,944 --> 00:09:39,459 So let's take a few minutes to consider some of the ways that we determine 100 00:09:39,459 --> 00:09:48,157 requirements for a few vitamins. When reviewing these slides, the details 101 00:09:48,157 --> 00:09:53,428 aren't as important. What I want you to get an idea of is how 102 00:09:53,428 --> 00:09:59,752 varied that the determinations can be. Just starting with Vitamin A. 103 00:09:59,752 --> 00:10:04,512 In determining Vitamin A status, numerous measures were brought together, to give 104 00:10:04,512 --> 00:10:08,906 an idea of how much Vitamin A should be stored in the body, if we're consuming 105 00:10:08,906 --> 00:10:11,550 enough. And the primary site where we store in 106 00:10:11,550 --> 00:10:14,949 the body is the liver. So that gave us a key location to look 107 00:10:14,949 --> 00:10:32,127 at, and a key thing to consider. So in this example we have a series of 108 00:10:32,127 --> 00:10:38,456 tests. Brought together to determine Vitamin A 109 00:10:38,456 --> 00:10:42,578 requirement. In the case of Vitamin B, we look more 110 00:10:42,578 --> 00:10:48,285 directly at blood values, as well as some measure of vitamin B activity. 111 00:10:51,381 --> 00:11:08,132 In the case of Folate, we have similar measures to vitamin B. 112 00:11:08,132 --> 00:11:22,317 Both cases showing actual blood measures as well as some enzyme or activity 113 00:11:22,317 --> 00:11:36,733 quotients or measure. In the case of Riboflavin, we consider not only the 114 00:11:36,733 --> 00:11:47,232 blood but also the urine. Here, we see an abbreviation. 115 00:11:47,232 --> 00:11:54,746 This stands for erythrocyte folate activity coefficient. 116 00:11:54,746 --> 00:12:03,928 And the more direct measure, the nonactive measure, is Urinary Riboflavin. 117 00:12:03,928 --> 00:12:11,357 But if you think about it. The Riboflavin that's made it to the 118 00:12:11,357 --> 00:12:16,427 urine is Riboflavin that's been processed. 119 00:12:18,407 --> 00:12:31,852 Thiamin again uses both blood and urine. Looking at direct measures and enzymatic 120 00:12:31,852 --> 00:12:41,012 measure. Niacin only looks at urine output. 121 00:12:41,012 --> 00:12:46,150 Once we scientifically derive the nutrient requirement, we can set an 122 00:12:46,150 --> 00:12:51,748 estimated average requirement, or EAR. This amount of a given nutrient will 123 00:12:51,748 --> 00:12:57,018 satisfy the needs of 50% of population. Then, by calculating 2 standard 124 00:12:57,018 --> 00:13:02,969 deviations above and below the EAR, we get the Recommended Dietary Allowance or 125 00:13:02,969 --> 00:13:06,318 RDA. This value, will be sufficient for 97 to 126 00:13:06,318 --> 00:13:10,749 98% of the population. We do not have scientific data, to 127 00:13:10,749 --> 00:13:14,643 support an EAR. We can extrapolate finding, and develop, 128 00:13:14,643 --> 00:13:19,817 an adequate intake, or AI value. An adequate intake level, is adequate for 129 00:13:19,817 --> 00:13:25,445 most people, and is often used, in recommendations for infants And children. 130 00:13:25,445 --> 00:13:30,352 Finally, we can also establish tolerable upper intake levels for UL. 131 00:13:30,352 --> 00:13:35,263 This is scientifically or clinically derived and prevents toxicity. 132 00:13:35,263 --> 00:13:40,935 This is mostly concerned when dealing with supplementaton rather than from food 133 00:13:40,935 --> 00:13:45,825 micro nutrients. Macro nutrient recommendations - first 134 00:13:45,825 --> 00:13:51,873 step to prevent disease either by deficiency or excess Keep in mind DRI 135 00:13:51,873 --> 00:13:58,916 values are set for population groups rather than individuals they can be used 136 00:13:58,916 --> 00:14:05,497 to assess adequacy of intake, plan diets and set policy and guidelines. 137 00:14:05,497 --> 00:14:12,492 Individuals should follow these recommendations with care, since we don't 138 00:14:12,492 --> 00:14:19,537 know the actual individual requirements. Using the RDA's and AI's targets and 139 00:14:19,537 --> 00:14:21,620 avoid exceeding the UL.