Module 1: Basic Nutrition FINAL Description Text Slide 1 Welcome to the Module Nutrition Basics

Module 1: Basic Nutrition FINAL Text Description Welcome to the module Nutrition Basics Slide 1 What is nutrition? The American Medical Association’s Council on Food and Nutrition defines nutrition as: "The science of food, the nutrients and the substances therein, their action, interaction, and balance in relation to health and disease, and the process by which the organism ingests, digests, absorbs, transports, utilizes and excretes food substances" Slide 2 So what does that actually mean? Nutrition is about food and what food is made of, and it also includes how food works in our bodies: how we eat, digest and use the food inside our bodies. Let’s sta rt with some ba sic definitions. A nutrient is a c hemic a l substa nc e in food tha t c ontributes to hea lth. Food provides both the energy a nd nutrients tha t our bodies need to c a rry out nec essa ry func tions. A food c onta ins a va riety of nutrients, a nd ea c h food provides different ones. There a re 3 things tha t ma ke a nutrient essentia l. 1) if left out of the diet, a dec line in hea lth will follow, 2) if restored before perma nent da ma ge oc c urs, hea lth should be rega ined, 3) a spec ific biologic a l func tion must be identified. An exa mple of a non essentia l nutrient is a lc ohol, a lthough some people get some of their energy inta ke from it, removing a lc ohol from the diet will not c a use a ny hea lth problems or defic ienc ies. Slide 3 We‘ll sta rt our look a t nutrition by investiga ting how we get the food we ea t from our pla te into our c ells. We do this through the proc ess of digestion. Digestion is the proc ess tha t brea ks down la rger molec ules by both mec ha nic a l a nd c hemic a l methods to produc e sma ller molec ules tha t c a n be a bsorbed. Wha t do we mea n by mec ha nic a l a nd c hemic a l methods? A mec ha nic a l method would be c hewing our food, where the c onta c t with our teeth helps to brea k down food into sma ller piec es. A c hemic a l method would inc lude the sec retion of hydroc hloric a c id in the stoma c h. Slide 4 The digestive proc ess oc c urs a long the entire G I tra c t, from the mouth to the a nus. Next, we’ll ta ke a look a t ea c h step in this proc ess in more deta il. Module 1: Basic Nutrition FINAL Text Description The digestive proc ess begins before you begin to ea t. Hea ting foods, c hopping a nd ma rina ting them a re a ll exa mples of how we begin to brea k down food before it even gets in our mouths. The sta rt of our digestive system is the mouth. Here, we c hew food, brea king it into sma ller piec es a nd mixing it with sa liva , whic h c onta ins enzymes tha t help brea k down molec ules. When we swa llow, food pa sses from the mouth through the esopha gus to the stoma c h. Slide 5 The stoma c h sec retes hydroc holoric a c id a nd enzymes to c ontinue to brea k food down. The stoma c h a lso c hurns food together, exposing it to the a c id a nd enzymes. The resulting soupy ma ss of food is c a lled c hyme. C hyme is usua lly rea dy to lea ve the stoma c h a bout 2 to 4 hours a fter a mea l. The sma ll intestine is ma de up of 3 sec tions: the duodenum, the jejunum a nd the ileum. There rea lly is nothing sma ll a bout the sma ll intestine. It wa s given the na me bec a use of its na rrow dia meter of a bout 1 inc h. The sma ll intestine is a bout 10 feet long! Slide 6 The ma jority of digestion is c ompleted in the duodenum a nd jejunum. Both enzymes a nd musc ula r c ontra c tions help with the proc ess, mixing the food a nd brea king it down a s it tra vels through the sma ll intestine. A mea l sta ys in the sma ll intestine for a bout 3 to 10 hours. The la rge intestine, a lso c a lled the c olon, is ma de up of 5 pa rts: the c ec um, the a sc ending c olon, tra nsverse c olon, desc ending c olon a nd the sigmoid c olon. The la rge intestine pa rtic ipa tes somewha t in digestion, but a bout 95% of digestion ha s oc c urred before food rea c hes the c olon. Food rema ins in the c olon for 24-72 hours before being elimina ted a s fec es. Slide 7 Module 1: Basic Nutrition FINAL Text Description Absorption is the proc ess by whic h nutrient molec ules a re a bsorbed by the G I tra c t a nd enter the bloodstrea m. This proc ess oc c urs mostly in the sma ll intestine, but the stoma c h a nd la rge intestine a re a lso involved to some extent. The effic ienc y of the sma ll intestine is due to its la rge surfa c e a rea . The wa lls of the sma ll intestine a re folded to inc rea se the surfa c e a rea , shown in figure 1. In a ddition, a ll a long the wa lls there a re villi: sma ll finger like projec tions tha t further inc rea se the surfa c e a rea , this is shown in figure 2 a nd 4. Along the c ells of the villi a re mic rovilli, even sma ller projec tions, shown in figure 3. Slide 8 This system of folds a nd projec tions inc rea ses the surfa c e a rea of the sma ll intestine to 600 times beyond tha t of a simple tube. After nutrients a re a bsorbed by the villi, they enter the bloodstrea m a nd begin to c irc ula te in the body one of two wa ys. Most nutrients go from the sma ll intestine to the porta l vein, whic h lea ds direc tly to the liver. This a llows the liver to proc ess the nutrients before they begin c irc ula ting through the rest of the body. Other nutrients a re a bsorbed into the lympha tic system, a nd enter the bloodstrea m via the left subc la via n vein in the nec k. Now we a re going to move on to looking a t the ma ke up of foods. We’ll sta rt by investiga ting c a lories a nd ma c ronutients, a lso known a s the energy c onta ining nutrients. Slide 9 A c a lorie is defined a s the a mount of energy needed to ra ise 1 kg of wa ter 1 degree c entigra de. The a mount of energy in a food is mea sured using a bomb c a lorimeter, a proc ess of burning a food in a c ha mber to determine the a mount of hea t given off. This hea t energy is c onverted to c a lories. This energy in the food c a n a lso be "burned" in our bodies to give us the energy tha t we need. Slide 10 Module 1: Basic Nutrition FINAL Text Description There a re 3 ma in c a tegories tha t ma ke up our use of food energy. Ba sil meta bolic ra te, or BMR, is ma de up of the ba sic body func tions required for life, this inc ludes things suc h a s brea thing a nd hea rt musc le c ontra c tions. BMR is a lso known a s resting energy expenditure. This will va ry depending on a ge, gender, body size, hea lth, a nd spec ia l fa c tors (for exa mple: pregna nc y, la c ta tion, a nd growth) Physic a l a c tivity is the c a tegory for energy expenditure due to movement. It c a n ra nge from sta nding up to running a ma ra thon. This will va ry from person to person a nd da y to da y. Slide 11 The thermic effec t of food, or TEF is the energy needed for the digestive system to c omplete the digestion a nd a bsorption of mea ls. <a href="/goto?url=http://www.c" target="_blank">Link http://www.c hoosemypla te.gov/mypla te/index.a spx </a>A ma c ronutrient is a nutrient tha t supplies energy. There a re 4 ma c ronutrients. They va ry on the a mount of energy they supply. C a rbohydra tes a nd protein ea c h provide 4 c a lories per gra m. Fa t provides 9 c a lories per gra m. Slide 12 It is importa nt to note tha t a lc ohol does c onta in energy itself, in a ddition to the c a lories from wha t it is mixed with. Alc ohol a lone provides 7 c a lories per gra m. The first ma c ronutrient tha t we will ta lk a bout is c a rbohydra tes. Slide 13 Slide 14 C a rbohydra tes a re the ma in sourc e of energy in the diet for most people a nd should provide more tha n 50% of energy inta ke. C a rbohydra te molec ules a re broken down to gluc ose, whic h is the ma in energy sourc e for red blood c ells, the bra in a nd the c entra l nervous system. Adequa te inta ke of c a rbohydra tes a lso prevents the brea kdown of protein from musc le tissues a nd fa tty a c ids from fa t c ells to c rea te gluc ose when there is not enough. If we ea t more c a rbohydra tes tha n we need for energy, our bodies c onvert them to store in the c ells. Some exc ess c a rbohydra tes a re c onverted to glyc ogen to be stored in liver a nd musc le tissues. G lyc ogen stored in the liver c a n be c onverted ba c k into gluc ose to help blood suga r levels rema in stea dy. Musc le glyc ogen c a nnot, but it c a n be used by musc les, espec ia lly during high intensity a nd endura nc e exerc ise. Slide 15 The rema inder of exc ess c a rbohydra tes a re meta bolized to triglyc erides a nd stored a s body fa t. Module 1: Basic Nutrition FINAL Text Description The c a rbohydra te group c onsists of 3 ma jor c a tegories: suga rs, sta rc hes a nd fiber. Slide 16 Monosa c c ha rides a nd disa c c ha rides a re c onsidered simple suga rs, mea ning tha t they require little or no digestion before they c a n be used by body. Monosa c c ha rides a re ma de up of just one molec ule. Disa c c ha rides a re ma de up of 2 molec ules. Suc rose, a lso known a s ta ble suga r, is ma de up of gluc ose a nd fruc tose bonded together. La c tose is the ma in suga r in milk. Ma ltose is less c ommonly c onsumed. Suga r a lc ohols a re often used in suga r free produc ts. Suga r a lc ohols a re not c ompletely a bsorbed, a nd therefore don’t provide a s muc h energy a s suga r, however, they a re pa rtia lly a bsorbed a nd provide a bout 2 c a lories per gra m. Suga r a lc ohols a re not the sa me a s suga r substitutes suc h a s Equa l or Splenda . It is a lso importa nt to note tha t when c onsumed in la rger a mounts, suga r a lc ohols c a n ha ve a la xa tive effec t so they should be c onsumed in modera tion. Slide 17 Suga r is the most c ommonly used food a dditive in Americ a . The a vera ge Americ a n c onsumes 82 gra ms of suga r per da y, whic h is a bout 6.5 ta blespoons or 2.5 c a ns of soda . Ma jor sourc es of suga r in the diet inc lude soft drinks, sweetened drinks, brea kfa st c erea ls, c ookies/pa stries/c a kes, juic e drinks, ic e c rea m, a nd frozen desserts. Slide 18 Meta a na lyses, or a review of multiple resea rc h studies, shows tha t less tha n 1% of the popula tion is sensitive to suga r inta ke, mea ning tha t inta kes of suga r ma y inc rea se a c tivity. Ac tive kids ma y a ppea r to ea t more suga r, but bec a use they expend more energy, they ea t more c a lories in genera l, so the proportion of suga r in their diet is simila r to less a c tive c hildren. Slide 19 Ac tive kids ma y a ppea r to ea t more suga r, but bec a use they expend more energy, they ea t more c a lories in genera l, so the proportion of suga r in their diet is simila r to less a c tive c hildren. Overa ll, there ha s been no da ta to support a link between suga r a nd hypera c tivity on popula tion level. Module 1: Basic Nutrition FINAL Text Description Sta rc hes a re c onsidered c omplex c a rbohydra tes with Oligosa c c ha rides c onta ining 3 to a bout 10 suga r molec ules. Polysa c c ha rides a re ma de up of ma ny suga r molec ules, up to 1000 or grea ter. Sta rc hes a re found in pla nt foods suc h a s gra ins, legumes a nd sta rc hy vegeta bles. Slide 20 Food ma nufa c turers c a n bond sta rc h molec ules together to ma ke them more sta ble, this is known a s modified food sta rc h a nd is used in ba by foods, sa la d dressings a nd puddings. Fiber is the fina l form of c a rbohydra tes. Fiber is not broken down by the digestive system, therefore, fiber is not a sourc e of energy. The two types of fiber a re insoluble a nd soluble fibers. Insoluble fiber does not dissolve in wa ter bec a use of the wa y it is bonded. In genera l, it is not digested by ba c teria in the la rge intestine. C ellulose a nd hemic ellulose a re types of insoluble fiber a nd often found in the struc tura l pa rts of the pla nt, suc h a s the skin of a n a pple or the bra n la yer of gra ins. The body uses this type of dieta ry fiber to inc rea se stool bulk a nd improve movement in the digestive system. Slide 21 Soluble fibers dissolve or swell when in wa ter. They c a n be meta bolized by ba c teria in the la rge intestine. Pec tin is found in fruits a nd vegeta bles, usua lly between c ell wa lls to hold c ells together. This type of dieta ry fiber c a n help lower blood c holesterol a nd blood gluc ose levels. Notic e tha t the buttons fill the ta sk ba r from left to right a s the folders a re opened. Adults need a bout 25-30 gra ms of dieta ry fiber per da y, a lthough the a vera ge da ily inta ke in the US is a bout 16-18 gra ms. C hildren need their a ge plus 5 gra ms per da y. Ina dequa te inta kes of fiber c a n lea d to c onstipa tion, divertic ulitis a nd other G I disorders. Slide 22 Module 1: Basic Nutrition FINAL Text Description Whole gra ins a re a good sourc e of fiber. A whole gra in c onta ins a ll three pa rts of the seed: bra n, endosperm a nd germ. The bra n a nd germ c onta in most of the vita mins, minera ls, fiber a nd protein found in the gra in seed. Refined gra ins ha ve been stripped of the bra n a nd germ, thus lea ding to a loss of nutrients a nd fiber. Some nutrients, suc h a s iron, thia mine, nia c in a nd ribofla vin a re a dded ba c k into refined gra ins, known a s enric hment. However, some nutrients c a nnot be a dded ba c k, inc luding ma gnesium, vita min B6, zinc , vita min E a nd fiber, ma king whole gra ins a muc h hea lthier option tha n refined gra ins. Slide 23 When c hoosing whole gra in produc ts, the first ingredient should inc lude the word “whole.” L<a href="/goto?url=http://www.wholegrainsc ounc il.org/" target="_blank">ink: http://www.wholeg</a><a href="/goto?url=http://www.wholegrainsc ounc il.org/" target="_blank">r</a><a href="/goto?url=http://www.wholegrainsc ounc il.org/" target="_blank">a</a><a href="/goto?url=http://www.wholegrainsc ounc il.org/" target="_blank"> </a><a href="/goto?url=http://www.wholegrainsc ounc il.org/" target="_blank">insc ounc il.org/ </a>The next ma c ronutrient we will be disc ussing is fa ts. Slide 24 Slide 25 Fa tty a c ids a re the building bloc ks of fa ts. The ba sic struc ture of a fa tty a c id is a c ha in of c a rbons with hydrogen a t either end. The struc ture of the fa tty a c ids determines whether a fa t will be liquid or solid a t room tempera ture. If a fa t is liquid a t room tempera ture it is unsa tura ted, a nd if a fa t is solid a t room tempera ture, it is sa tura ted. Fa tty a c ids a re the building bloc ks of fa ts. The ba sic struc ture of a fa tty a c id is a c ha in of c a rbons with hydrogen a t either end. The struc ture of the fa tty a c ids determines whether a fa t will be liquid or solid a t room tempera ture. If a fa t is liquid a t room tempera ture it is unsa tura ted, a nd if a fa t is solid a t room tempera ture, it is sa tura ted. Sa tura ted fa tty a c ids a re c ha ra c terized by ha ving no double bonds between the c a rbons in the c ha in. Bec a use of their struc ture, sa tura ted fa tty a c ids a re usua lly solid a t room tempera ture. C ommon sourc es of sa tura ted fa ts inc lude butter, a nima l fa ts, whole milk, c oc onut a nd pa lm kernel oils. High inta kes of sa tura ted fa ts in the diet ha ve been linked to high blood c holesterol levels a nd a n inc rea sed risk of c a rdiova sc ula r disea se.

Module 1: Basic Nutrition FINAL Description Text Slide 1 Welcome to the Module Nutrition Basics

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