{"id":18278,"date":"2014-11-07T10:38:18","date_gmt":"2014-11-07T09:38:18","guid":{"rendered":"http:\/\/www.invarena.cz\/?p=18278"},"modified":"2014-11-07T10:38:18","modified_gmt":"2014-11-07T09:38:18","slug":"nepravdive-se-rika-o-kave-ze","status":"publish","type":"post","link":"https:\/\/www.invarena.cz\/?p=18278","title":{"rendered":"Nepravdiv\u011b se \u0159\u00edk\u00e1 o k\u00e1v\u011b, \u017ee \u2026"},"content":{"rendered":"

Je pit\u00ed k\u00e1vy \u0161kodliv\u00e9 nebo naopak zdrav\u00e9? Den\u00edk Hal\u00f3 noviny vyvrac\u00ed n\u011bkter\u00e9 m\u00fdty, kter\u00e9 o tomto proslul\u00e9m n\u00e1poji panuj\u00ed…<\/strong> <\/p>\n

\u2026\u0161kod\u00ed zdrav\u00ed<\/p>\n

P\u0159im\u011b\u0159en\u00e1 konzumace k\u00e1vy p\u0159edstavuje prevenci proti cel\u00e9 \u0159ad\u011b nemoc\u00ed, nap\u0159. Parkinsonov\u011b chorob\u011b nebo diabetu mellitu 2. typu. D\u00edky obsahu antioxidant\u016f m\u00e1 k\u00e1va podobn\u00e9 p\u0159\u00edzniv\u00e9 antiaterogenn\u00ed a kardioprotektivn\u00ed \u00fa\u010dinky jako zelen\u00fd \u010daj nebo \u010derven\u00e9 v\u00edno.<\/p>\n

\u2026podporuje vznik rakoviny<\/p>\n

P\u016fvodn\u00ed obavy z mo\u017en\u00fdch karcinogenn\u00edch \u00fa\u010dink\u016f k\u00e1vy rozpt\u00fdlily nejnov\u011bj\u0161\u00ed v\u00fdzkumy a studie t\u00fdkaj\u00edc\u00ed se k\u00e1vy a jej\u00edho vlivu na rakovinu. Zjistila se negativn\u00ed korelace mezi pit\u00edm k\u00e1vy a zhoubn\u00fdmi n\u00e1dorov\u00fdmi chorobami. Tento ochrann\u00fd efekt k\u00e1vy se p\u0159ipisuje obsahu antioxida\u010dn\u00edch l\u00e1tek. Pozitivn\u00ed zdravotn\u00ed<\/span> \u00fa\u010dinky k\u00e1vy (antikarcinogenn\u00ed, antiaterogenn\u00ed, antidiabetick\u00e9 a dal\u0161\u00ed) jsou dnes u\u017e tak z\u0159ejm\u00e9, \u017ee se zm\u00ednky o nich dostaly i do u\u010debnic klinick\u00e9 dietologie.<\/p>\n

\u2026nen\u00ed vhodn\u00e1 pro t\u011bhotn\u00e9 a koj\u00edc\u00ed \u017eeny<\/p>\n

V\u011bt\u0161ina \u017een se nemus\u00ed sv\u00e9 obl\u00edben\u00e9 k\u00e1vy vzd\u00e1t ani v tomto obdob\u00ed. Studie prok\u00e1zaly, \u017ee mal\u00e9 mno\u017estv\u00ed k\u00e1vy v t\u011bhotenstv\u00ed (do 150 mg kofeinu denn\u011b, tj. 2 a\u017e 3 \u0161\u00e1lky) nem\u00e1 negativn\u00ed vliv na v\u00fdvoj plodu ani na vznik komplikac\u00ed. P\u0159i kojen\u00ed je povolen\u00e1 d\u00e1vka kofeinu 200 mg denn\u011b.<\/p>\n

\u2026zvy\u0161uje krevn\u00ed tlak<\/p>\n

B\u011b\u017en\u00e9 d\u00e1vky k\u00e1vy rizikov\u00e9 nejsou, k\u00e1vu si mohou dovolit i lid\u00e9 s kardiovaskul\u00e1rn\u00edmi nemocemi. U toho, kdo k\u00e1vu nepije pravideln\u011b, m\u016f\u017ee doj\u00edt k m\u00edrn\u00e9mu zv\u00fd\u0161en\u00ed krevn\u00edho tlaku, ale na kofein se rychle vyvine tolerance a tlak se vr\u00e1t\u00ed na v\u00fdchoz\u00ed hodnotu.<\/p>\n

\u2026nem\u00e1 se p\u00edt na la\u010dno<\/p>\n

Kofein povzbuzuje produkci \u017ealude\u010dn\u00edch \u0161\u0165\u00e1v, a t\u00edm p\u0159ipravuje tr\u00e1vic\u00ed syst\u00e9m na tr\u00e1ven\u00ed potravy. Je tedy lep\u0161\u00ed, pokud je k\u00e1va n\u00e1sledov\u00e1na konzumac\u00ed j\u00eddla. P\u0159esto by u zdrav\u00e9ho \u010dlov\u011bka nem\u011bla vyvolat zdravotn\u00ed<\/span> obt\u00ed\u017ee. U pacient\u016f se z\u00e1n\u011btem \u017ealudku nebo v\u0159edovou chorobou \u017ealudku je vhodn\u00e9 si k\u00e1vu odpustit.<\/p>\n

\u2026zp\u016fsobuje \u017eloutnut\u00ed zub\u016f<\/p>\n

I kdy\u017e se traduje, \u017ee pit\u00ed k\u00e1vy negativn\u011b p\u016fsob\u00ed na zabarven\u00ed a kvalitu zubn\u00ed skloviny a souvis\u00ed s tvorbou zubn\u00edho plaku, odborn\u00e9 studie to vyvracej\u00ed. Ital\u0161t\u00ed v\u011bdci z Anconsk\u00e9 univerzity zato narazili p\u0159i laboratorn\u00edch testech na l\u00e1tku, kter\u00e1 zabra\u0148uje \u0161\u00ed\u0159en\u00ed bakteri\u00ed napadaj\u00edc\u00edch zuby a zp\u016fsobuj\u00edc\u00edch jejich kazivost.<\/p>\n

\u2026dehydratuje, je mo\u010dopudn\u00e1<\/p>\n

K\u00e1va organizmus nedehydruje, je naopak v\u00fdznamn\u00fdm p\u0159\u00edsp\u011bvkem k celkov\u00e9mu denn\u00edmu p\u0159\u00edjmu tekutin. Doporu\u010den\u00e9 denn\u00ed mno\u017estv\u00ed kofeinu p\u0159edstavuje 4 a\u017e 6 \u0161\u00e1lk\u016f, tj. asi p\u016fl litru k\u00e1vy. Tato d\u00e1vka nep\u016fsob\u00ed siln\u011b mo\u010dopudn\u011b. Po po\u010d\u00e1te\u010dn\u00ed konzumaci k\u00e1vy se sice zvy\u0161uje pot\u0159eba mo\u010den\u00ed, ale ta p\u0159i dal\u0161\u00ed konzumaci ji\u017e nestoup\u00e1. Jinak je tomu v p\u0159\u00edpad\u011b p\u0159ehnan\u00e9ho pit\u00ed k\u00e1vy, kter\u00e9 se projevuje vylu\u010dov\u00e1n\u00edm zdrav\u00ed prosp\u011b\u0161n\u00fdch l\u00e1tek z t\u011bla (v\u00e1pn\u00edk aj. miner\u00e1ln\u00ed l\u00e1tky) a tak\u00e9 celkov\u00fdm odvodn\u011bn\u00edm. V takov\u00e9m p\u0159\u00edpad\u011b je vhodn\u00e9 dopl\u0148ovat do organizmu vodu.<\/p>\n

\u2026espresso je siln\u011bj\u0161\u00ed
\na \u00fa\u010dinn\u011bj\u0161\u00ed<\/p>\n

\u00da\u010dinky kofeinu jsou z\u00e1visl\u00e9 p\u0159edev\u0161\u00edm na d\u00e1vce k\u00e1vy a v n\u00ed obsa\u017een\u00e9m mno\u017estv\u00ed kofeinu, ale tak\u00e9 na rychlosti, jakou k\u00e1vu vypijeme. Pocit p\u0159i pit\u00ed k\u00e1vy ovliv\u0148uje i mno\u017estv\u00ed pou\u017eit\u00e9 vody. Stejn\u00e9 mno\u017estv\u00ed mlet\u00e9 zrnkov\u00e9 k\u00e1vy bude chutnat v espressu s mal\u00fdm mno\u017estv\u00edm vody jako siln\u00e1 k\u00e1va. Nav\u00edc ho vypijeme podstatn\u011b rychleji ne\u017e velk\u00fd objem p\u0159ekap\u00e1van\u00e9 k\u00e1vy. P\u0159itom mno\u017estv\u00ed pou\u017eit\u00e9 k\u00e1vy a tedy i kofeinu m\u016f\u017ee b\u00fdt stejn\u00e9.<\/p>\n

\u2026ml\u00e9ko potla\u010duje
\n\u00fa\u010dinky kofeinu<\/p>\n

Ml\u00e9ko tlum\u00ed \u00fa\u010dinek kofeinu pouze na sliznici \u017ealudku, proto je k\u00e1va s ml\u00e9kem doporu\u010dov\u00e1na u onemocn\u011bn\u00ed \u017ealudku. Ml\u00e9ko a je\u0161t\u011b v\u00edce smetana v\u0161ak zpomaluje vyprazd\u0148ov\u00e1n\u00ed \u017ealudku a s n\u00edm i rychlost vst\u0159eb\u00e1v\u00e1n\u00ed kofeinu. N\u00e1stup \u00fa\u010dinku kofeinu je proto pomalej\u0161\u00ed, doba p\u016fsoben\u00ed del\u0161\u00ed a konzument m\u016f\u017ee m\u00edt pocit, \u017ee k\u00e1va s ml\u00e9kem je sv\u00fdmi \u00fa\u010dinky slab\u0161\u00ed ne\u017e samotn\u00e1 \u010dern\u00e1 k\u00e1va. Stejn\u011b ale p\u016fsob\u00ed i j\u00eddlo konzumovan\u00e9 spole\u010dn\u011b s k\u00e1vou. Nejrychlej\u0161\u00ed n\u00e1stup \u00fa\u010dinku m\u00e1 k\u00e1va konzumovan\u00e1 na la\u010dno.<\/p>\n

\u2026m\u016f\u017ee vyvolat
\nz\u00e1vislost<\/p>\n

U k\u00e1vy se ned\u00e1 hovo\u0159it o klasick\u00e9 z\u00e1vislosti, av\u0161ak m\u016f\u017ee nastat ur\u010dit\u00e1 podoba zv\u00fd\u0161en\u00e9 tolerance k \u00fa\u010dink\u016fm kofeinu, kter\u00fd stimuluje centr\u00e1ln\u00ed nervovou soustavu. Proto\u017ee kofein se na rozd\u00edl od tradi\u010dn\u00edch drog u\u017e\u00edv\u00e1 or\u00e1ln\u011b a v pr\u016fb\u011bhu dne, jeho absorpce je zpomalen\u00e1, co\u017e sni\u017euje riziko vzniku z\u00e1vislosti. U drog d\u00e1vka pot\u0159ebn\u00e1 k dosa\u017een\u00ed po\u017eadovan\u00e9 euforie nebo posiluj\u00edc\u00edch \u00fa\u010dink\u016f roste v \u010dase a podn\u011bcuje k bran\u00ed st\u00e1le v\u011bt\u0161\u00edho mno\u017estv\u00ed drogy. V\u011bt\u0161ina konzument\u016f k\u00e1vy udr\u017euje svoji spot\u0159ebu na celkem konstantn\u00ed \u00farovni.<\/p>\n

\u2026zelen\u00e1 k\u00e1va \u2013 z\u00e1zrak na hubnut\u00ed<\/p>\n

Pokud se t\u00fdk\u00e1 zelen\u00e9 k\u00e1vy, v\u00fdt\u011b\u017enost z\u00edsk\u00e1n\u00ed jak alkaloid\u016f, tak antioxidant\u016f je pom\u011brn\u011b mal\u00e1, bylo by to podobn\u00e9, jako bychom se sna\u017eili konzumovat p\u0161eni\u010dn\u00e9 zrno bez uva\u0159en\u00ed \u2013 syrov\u00e9, t\u00e9\u017e v\u00fdt\u011b\u017enost z\u00edsk\u00e1n\u00ed sacharid\u016f \u010di stravitelnost by byla velmi miziv\u00e1, podobn\u011b je tomu i u zelen\u00e9 k\u00e1vy. Pohl\u00ed\u017eet tedy na zelenou k\u00e1vu jako na z\u00e1zra\u010dn\u00fd prost\u0159edek k hubnut\u00ed, je naprosto neopodstatn\u011bn\u00e9.<\/p>\n

\u2026po povzbuzen\u00ed p\u0159ich\u00e1z\u00ed v\u011bt\u0161\u00ed \u00fatlum<\/p>\n

Povzbuzuj\u00edc\u00ed \u00fa\u010dinek k\u00e1vy je nejz\u0159eteln\u011bj\u0161\u00ed, kdy\u017e se k\u00e1va konzumuje ve stavu p\u0159irozen\u00e9 \u00fanavy. Nap\u0159\u00edklad p\u0159i pit\u00ed k\u00e1vy v no\u010dn\u00edch hodin\u00e1ch p\u0159i pr\u00e1ci nebo studiu za \u00fa\u010delem povzbuzen\u00ed bd\u011blosti a psychick\u00e9ho v\u00fdkonu. Po do\u010dasn\u00e9m povzbuzen\u00ed a zlep\u0161en\u00ed psychomotorick\u00e9ho v\u00fdkonu v\u0161ak nast\u00e1v\u00e1 \u00fatlum a vystup\u0148ovan\u00fd pocit \u00fanavy. N\u00e1sledn\u00e1 \u00fanava ov\u0161em nen\u00ed p\u0159\u00edm\u00fdm \u00fa\u010dinkem kofeinu. Jde o kombinovan\u00fd efekt ukon\u010den\u00ed psychostimula\u010dn\u00edho \u00fa\u010dinku kofeinu a pokro\u010dilej\u0161\u00edho stupn\u011b fyziologick\u00e9 \u00fanavy, ke kter\u00e9 by do\u0161lo i bez konzumace k\u00e1vy.<\/p>\n

\u2026nem\u016f\u017ee vyvolat akutn\u00ed otravu<\/p>\n

Za smrtelnou d\u00e1vku kofeinu p\u0159ijatou peror\u00e1ln\u011b se pova\u017euje jednor\u00e1zov\u00e1 d\u00e1vka 150 mg kofeinu na 1 kg t\u011blesn\u00e9 hmotnosti, to znamen\u00e1 kolem 10 g kofeinu u norm\u00e1ln\u00edho \u010dlov\u011bka. P\u0159ed\u00e1vkov\u00e1n\u00ed (jednor\u00e1zov\u00e1 d\u00e1vka kofeinu kolem 0,5 a\u017e 1 g) se projev\u00ed neklidem, agitovanost\u00ed, zrychlenou srde\u010dn\u00ed akc\u00ed, nespavost\u00ed, \u010dast\u00fdm mo\u010den\u00edm. \u010clov\u011bk je p\u0159i v\u011bdom\u00ed, velmi vzru\u0161iv\u00fd, ale p\u0159\u00edpadn\u00e9 informace nen\u00ed schopen ulo\u017eit \u2013 p\u0159ehnan\u00e1 konzumace k\u00e1vy proto rozhodn\u011b nen\u00ed vhodn\u00e1 pro studenty.<\/p>\n

foto: David Leo Veksler \/ Flickr.com<\/p>\n

Hal\u00f3 noviny<\/p>\n","protected":false},"excerpt":{"rendered":"

Je pit\u00ed k\u00e1vy \u0161kodliv\u00e9 nebo naopak zdrav\u00e9? Den\u00edk Hal\u00f3 noviny vyvrac\u00ed n\u011bkter\u00e9 m\u00fdty, kter\u00e9 o tomto proslul\u00e9m n\u00e1poji panuj\u00ed…<\/p>\n<\/div>","protected":false},"author":1,"featured_media":18163,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11],"tags":[],"class_list":["post-18278","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-zdravi"],"_links":{"self":[{"href":"https:\/\/www.invarena.cz\/index.php?rest_route=\/wp\/v2\/posts\/18278","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.invarena.cz\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.invarena.cz\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.invarena.cz\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.invarena.cz\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=18278"}],"version-history":[{"count":0,"href":"https:\/\/www.invarena.cz\/index.php?rest_route=\/wp\/v2\/posts\/18278\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.invarena.cz\/index.php?rest_route=\/wp\/v2\/media\/18163"}],"wp:attachment":[{"href":"https:\/\/www.invarena.cz\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=18278"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.invarena.cz\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=18278"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.invarena.cz\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=18278"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}