Kowace rana muna yin watsi da hikimar falsafa da gastronomic da Socrates ya yi shelar cewa: “Kuna bukatar ku ci don ku rayu, ba rayuwa ku ci ba.” Menene ke sa mutum ya yi sakaci na dabi'a, siginar da aka ba shi ("Na ƙoshi, ba na so in ci abinci kuma") don neman cin abinci mai yawa don jin daɗi da ke cutar da jiki?
Lokacin da mutane masu kiba suka ga abinci mai kalori mai yawa, manyan wuraren da ke da alhakin jin daɗi, hankali, motsin rai, ƙwaƙwalwar ajiya da ƙwarewar motsa jiki ana kunna su a cikin kwakwalwarsu, nazarin ta yin amfani da hoton haɓakar maganadisu na aiki ya nuna. Har yanzu ba a san dalilin da yasa mutane ke yin kiba: saboda jikinsu ba shi da ikon sarrafa kansa na nauyi, ko kuma saboda jiki ya rasa wannan ikon yayin samun kiba mai yawa.
Tsarin narkewa kamar yadda kuka sani, yana farawa tun kafin abinci ya shiga ciki har ma cikin baki. Ganin abinci, kamshinsa, ko ma kalmar da ta kira shi, suna motsa sassan kwakwalwar da ke da alhakin samun ni'ima, suna kunna cibiyoyin ƙwaƙwalwar ajiya da kuma salivary gland. Mutum yana cin abinci ko da bai ji yunwa ba, domin yana ba da jin daɗi. Menene ke sa mutum ya yi sakaci na dabi'a, siginar da aka ba shi ("Na ƙoshi, ba na so in ci abinci kuma") don neman cin abinci mai yawa don jin daɗi da ke cutar da jiki?
Masana kimiyya daga Jami'ar Columbia (New York) sun gabatar da takarda kan abubuwan da ke haifar da kiba a wurin taro kan kiba a Stockholm.
Cikakkun taswirar ayyukan kwakwalwa ya nuna yadda begen jin daɗin abinci mai daɗi ke kayar da ikon da jiki ke da shi na daidaita nauyi da kuma kariya daga yawan cin abinci.
Masana kimiyya sun lakaba irin wannan nau'in abinci mai gina jiki "hedonic" da "homeostatic" bi da bi (homeostasis shine ikon jiki don daidaita kansa, kiyaye daidaito mai ƙarfi). Ya fito, musamman, cewa kwakwalwar mutane masu kiba suna amsawa da "hedonistically" ga abinci mai dadi da mai mai yawa fiye da kwakwalwar mutanen da ke da nauyin al'ada. Ƙwaƙwalwar masu kiba tana mayar da martani da ƙarfi har ma da hotunan abinci masu jaraba.
Likitoci sun yi nazarin halayen kwakwalwa zuwa hotuna "cin abinci" ta amfani da hoton aikin maganadisu (fMRI). Binciken ya shafi mata 20 - 10 kiba da 10 na al'ada. An nuna musu hotunan abinci mai ban sha'awa: kek, pies, soyayyen faransa, da sauran abinci masu yawan kalori. Binciken MRI ya nuna cewa a cikin mata masu kiba, hotunan suna da kwakwalwa masu aiki sosai a cikin yanki na ventral tegmental (VTA), wani karamin batu a cikin tsakiyar kwakwalwa inda aka saki dopamine, "neurohormone na sha'awar," an saki.
"Lokacin da mutane masu kiba suka ga abinci mai kalori mai yawa, manyan wurare a cikin kwakwalwar su suna kunnawa waɗanda ke da alhakin ji na lada, hankali, motsin rai, ƙwaƙwalwar ajiya da ƙwarewar mota. Duk waɗannan wuraren suna hulɗa, don haka yana da wahala hanyoyin sarrafa kai na dabi'a su bijire musu, "in ji Susan Carnell, likitan hauka a Jami'ar Columbia.
A cikin ƙungiyar kulawa - mata masu siririn - ba a lura da irin waɗannan halayen ba.
Ƙara yawan ci a cikin mutane masu kiba ba kawai ta hanyar hotunan abinci ba ne ya haifar da su. Sauti, kamar kalmomin "kuki cakulan" ko sunayen wasu magunguna masu yawan kalori, sun haifar da irin wannan martanin kwakwalwa. Sautin kalmomi don lafiya, abinci mai ƙarancin kalori, irin su "kabeji" ko "zucchini," ba su haifar da wannan amsa ba. Ƙwaƙwalwar mata masu siriri sun yi raunanniyar amsa ga "sauti masu daɗi".
An gabatar da irin wannan binciken a wani taron abinci mai gina jiki a Pittsburgh. Likitocin Neurologists daga Jami'ar Yale sun gudanar da wani binciken fMRI na kwakwalwar 13 masu kiba da kuma siriri 13. Yin amfani da na'urar daukar hoto, an rubuta martanin kwakwalwa ga wari ko ɗanɗanon cakulan ko madarar strawberry. An lura da halayen kwakwalwar mutane masu kiba ga abinci a cikin yankin amygdala na cerebellum - tsakiyar motsin rai. Sun “ dandana” abinci mai daɗi ko suna jin yunwa ko a’a. Cerebellum na mutanen da ke da nauyin al'ada sun amsa ga milkshake kawai lokacin da mutum ya sami jin yunwa.
"Idan nauyin ku bai wuce na al'ada ba, hanyoyin homeostasis suna aiki yadda ya kamata kuma suna samun nasarar sarrafa wannan yanki na kwakwalwa. Duk da haka, idan kun kasance mai kiba, akwai wani nau'i na rashin aiki na siginar homeostatic, don haka masu kiba sukan shiga jarabawar abinci, ko da sun cika gaba daya, "in ji shugaban binciken Dana Small.
“Abincin abinci” na abinci mai kitse da mai na iya dushe ginannun hanyoyin daidaita nauyi a jikin mutum gaba ɗaya. A sakamakon haka, tsarin narkewa ya daina samar da "saƙonnin" sinadarai, musamman ma furotin cholecystokinin, wanda "ya ba da rahoton" satiety. Wannan sinadari dole ne ya tafi zuwa kwakwalwar kwakwalwa sannan zuwa ga hypothalamus, kuma dole ne kwakwalwa ta ba da umarnin daina cin abinci. Ga masu kiba, wannan sarkar ta katse, sabili da haka, za su iya daidaita tsawon lokaci da yawan abincin daga waje kawai, ta hanyar "yanke shawara".
Wani abu mai mahimmanci bai bayyana ba daga binciken da aka yi, a cikin ruhun "wanda ya fara zuwa, kaza ko kwai." Shin mutane suna samun kiba ne saboda tun farko jikinsu ba zai iya daidaita nauyin jiki da kansa ba, ko kuma jikin ya rasa wannan karfin yayin da ya wuce kiba?
Dokta Small ya yi imanin cewa duka matakai suna da alaƙa. Na farko, cin zarafi na rage cin abinci yana haifar da rashin aiki na hanyoyin homeostatic a cikin jiki, sa'an nan kuma rashin lafiya na rayuwa yana haifar da ci gaba mai girma. “Muguwar da’ira ce. Yayin da mutum ya ci abinci, hakan yana kara fuskantar barazanar cin abinci da yawa,” inji ta. Ta hanyar binciken abubuwan da ke tattare da kiba a cikin siginar kwakwalwa, masana kimiyya suna fatan za su fahimci cikakkiyar "cibiyoyin cikawa" a cikin kwakwalwa kuma su koyi yadda za a daidaita su daga waje, a cikin sinadarai. Hasashen "kwayoyin slimming" a cikin wannan yanayin ba za su kai ga asarar nauyi ba, amma za su dawo da damar iyawar jiki ta yadda ya gane yanayin satiety.
Duk da haka, hanya mafi kyau don kada ku rushe waɗannan hanyoyin ba don fara samun mai ba, likitoci sun tunatar da su. Yana da kyau a nan da nan sauraron siginar jiki "isa!", Kuma kada ku yarda da jarabar shan shayi tare da kukis da cake, kuma lalle ne ku sake yin la'akari da abincin ku don cin abinci maras nauyi da sauƙi.