M²ty o bφlkovinßch
Donedßvna se tvrdilo, ₧e vegetarißn∙m hrozφ nedostatek bφlkovin a tudφ₧ ·bytek svalovΘ hmoty a eventußlnφ podv²₧iva. Bylo to zd∙vod≥ovßno tak, ₧e ₧ivoΦiÜnΘ bφlkoviny jsou kvalitn∞jÜφ ne₧ rostlinnΘ. Jen₧e odkud se vlastn∞ tento nßzor vzal? Jak vlastn∞ vznikl m²tus o tom, ₧e rostlinnΘ bφlkoviny jsou horÜφ?
V roce 1914 v²zkumnφci Osborne a Mendel provßd∞li pokusy na krysßch. Zjistili, ₧e tato zvφ°ata rostou pomaleji, kdy₧ jsou krmena rostlinn²mi bφlkovinami, ne₧ kdy₧ jedφ ₧ivoΦiÜnΘ bφlkoviny. Z toho uΦinili zßv∞r, ₧e ₧ivoΦiÜnΘ bφlkoviny jsou kvalitn∞jÜφ ne₧ rostlinnΘ bφlkoviny, kterΘ oznaΦili za horÜφ, "druho°adΘ".
╚φm ale byly tyto v²sledky zp∙sobeny? Je to dßno tφm, ₧e mlß∩ata krys rostou mnohem rychleji ne₧ naÜe lidskΘ d∞ti. Je to vid∞t na porovnßnφ Φasu, za n∞j₧ se zdvojnßsobφ porodnφ hmotnost u mlß∩at. U lidφ je to 180 dnφ, kde₧to u krys 4 a₧ 5 dnφ. Z toho d∙vodu tedy krysφ mlß∩ata pot°ebujφ mnohem koncentrovan∞jÜφ zdroje vÜech ₧ivin a tedy i bφlkovin. Je to jasn∞ vid∞t, srovnßme-li mate°skΘ mlΘko obou druh∙. LidskΘ mate°skΘ mlΘko obsahuje okolo 7% kalorickΘho obsahu ve form∞ bφlkovin (vßhov∞ 1,2 g/100 ml), zatφmco krysφ mlΘko okolo 20% kalorickΘho obsahu v bφlkovinßch (vßhov∞ 11,8 g/100 ml).
Kdyby tedy p°i zmφn∞n²ch v²zkumech v∞dci krmili krysφ mlß∩ata lidsk²m mate°sk²m mlΘkem, takΘ by zjistili, ₧e malΘ krysy pomalu rostou. A tedy, u₧φvajφce stejnou logiku, by mohli tvrdit, ₧e i lidskΘ mate°skΘ mlΘko je Üpatn²m zdrojem bφlkovin a ₧e tudφ₧ nenφ "plnohodnotnΘ". Ale lidΘ p°ece nejsou krysy a tak se tyto v²sledky nemohou automaticky aplikovat na lidi.
Druh² m²tus t²kajφcφ se bφlkovin p°iÜel z neΦekanΘho zdroje - na konci 60-t²ch let byla vydßna dnes ji₧ legendßrnφ kniha "Diet for a Small Planet", kterß odhalila °adu ot°esn²ch fakt∙, souvisejφcφch s vysokou konzumacφ masa. (Celkem se jφ prodalo okolo 3 milion∙ v²tisk∙.) Jeliko₧ v tΘ dob∞ byl m²tus o "neplnohodnotnosti" rostlinn²ch bφlkovin jeÜt∞ velmi siln², sna₧ila se kniha popularizovala myÜlenku "kompletovßnφ bφlkovin" z r∙zn²ch rostlinn²ch jφdel, aby ve strav∞ byly zastoupeny v₧dy vÜechny pot°ebnΘ esencißlnφ aminokyseliny. Zßm∞r byl jist∞ chvßlyhodn², pramenφcφ z nejlepÜφch ·mysl∙, ale bohu₧el to ve svΘ dob∞ jen posφlilo vφru v "neplnohodnotnost" rostlinn²ch zdroj∙ bφlkovin. V nßsledujφcφch vydßnφch knihy byl tento omyl opraven, ale bohu₧el dosud p°e₧φvß, mimo jinΘ i proto, ₧e ho zaΦali hojn∞ pou₧φvat zastßnci konzumace masa.
(Zdroj: http://www.afpafitness.com/Vegetarian.htm - AFPA - American Fitness Professionals And Associates
s pou₧itφm knihy - Cox, P., The Realeat Encyclopedia of Vegetarian Living
a ╚ervanß, D., ╚erven², K., LΘΦba v²₧ivou, Neografie, Martin, 1994)
DalÜφ literatura o bφlkovinßch:
- Protein Myths. (Essential Nutrients and Their Functions) Henry Ginsberg. The Columbia Univ. Coll. of Physicians & Surgeons Complete Home Medical Guide Edition 3, 1995 p88(1)
- High-protein diets: where's the beef? (diets that discount carbohydrates in favor of high-protein diets can cause lose of needed water and other nutrients: includes a related article on 'The Zone' and other disputed diet books) Eileen Norris. Harvard Health Letter Jan 1997 v22 n3 p1(3)
- So-called "new" high-protein diets are the same old bad news. Environmental Nutrition Dec. 1996 v19 n12 p3(1)
- The new diet food: high-protein diets really do make you lose fat; that's where the problems start. (includes related article on fad diet books) Wendy Marston. Health Sept 1996 v10 n5 p98(4)
- The 'pros' of protein for enhancing athletes' performance and health. Patricia Andersen-Parrado. Better Nut Aug. 1996 v58 n8 p36(1)
- Here we go again. (new diet books advocating a return to high-protein, meat-based diets)(Editorial) Catherine Censor Shemo. Vegetarian Times June 1996 n226 p6(1)
- Entering a high-protein twilight zone. (high-protein diet myths) Tufts University Diet & Nutrition Letter May 1996 v14 n3 p4(2)
- High-energy, high-protein, oral, liquid, nutrition supplementation in patients with HIV infection: effect on weight status in relation to incidence of secondary infection. Jennifer A. Stack, Stacey J. Bell, Peter A. Burke, R. Armour Forse. Journal of the American Dietetic Association April 1996 v96 n4 p337(5)
- The protein myth. Robert M. Kradjian. Nutrition Health Review Summer 1995 n73 p13(1)
- Relationship between dietary protein and pressure ulcers. (Bedsores) American Family Physician Sept 15, 1993 v48 n4 p663(1)
- The chicken breast myth. (protein in the diet) (Column) Judith Mandelbaum-Schmid. Health Sept 1993 v7 n5 p26(2)
- Does a high-protein diet mean a high risk of cancer? The Edell Health Letter June-July 1993 v12 n6 p5(1)
- The problem with protein. (too much protein in the diet may increase risk of some diseases)(includes related articles) (Cover Story) David Schardt. Nutrition Action Health letter June 1993 v20 n5 p1(4)
- High-protein diet can promote healing of pressure ulcers. The Brown University Long-Term Care Quality Let May 25, 1993 v5 n10 p4(1)
- Low-carbohydrate, high-protein diet: the way to lose weight? The University of California, Berkeley Wellness Let Dec. 1992 v9 n3 p1(1)
- Diet and colorectal cancer in Russia. (Diet and Cancer) Nutrition Research Newsletter Nov-Dec 1992 v11 n11-12 p125(2)
- Dietary management of malnourished children with a new enteral feeding. Enrique Morales, Lisa D. Craig, William C. MacLean Jr. Journal of the American Dietetic Association Oct. 1991 v91 n10 p1233(6)
- Effect of meal composition on satiety. (Weight Control) Nutrition Research Newsletter Feb. 1991 v10 n2 p16(1)
- Things nobody ever told Rocky Balboa about protein. (Special Report) Tufts University Diet & Nutrition Letter Feb. 1991 v8 n12 p3(4)
- China's blockbuster diet study. (diet and disease) Jane E. Brody. Saturday Evening Post Oct. 1990 v262 n7 p30(3)
- Fat and fiction: calorie for calorie, the thin gain more- and other weighty findings. Peter L. Weiss. Sci News Sept 1, 1990 v138 n9 p138(2)
- The protein issue and vegetarianism. (high-protein diets may increase chances of osteoporosis; includes vegetarian recipes) (column) Ron Pickarski. Total Health June 1990 v12 n3 p25(3)
- The protein myth: when too much of a good thing is a bad thing. Mervyn G. Hardinge, William C. Andress. Vibrant Life Jan-Feb. 1990 v6 n1 p24(4) Harvard Health Letter, Jan 1997 v22 n3 p1(3)
- High-protein diets: where's the beef? (diets that discount carbohydrates in favor of high-protein diets can cause lose of needed water and other nutrients: includes a related article on 'The Zone' and other disputed diet books) Eileen Norris.