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1、HealthydietAhealthydietisonethatisarrivedatwiththeintentofimprovingormaintainingoptimalhealth.Thisusuallyinvolvesconsumingnutrientsbyeatingtheappropriateamountsfromallofthefoodgroups,includinganadequateamountofwater.Sincehumannutritioniscomplex,ahealthydietmayvarywidely,andissubjectto
2、anindividual'sgeneticmakeup,environment,andhealth.Foraround21%ofthehumanpopulation,lackoffoodandmalnutritionarethemainimpedimentstohealthyeating.[citationneeded]Conversely,peopleindevelopedcountrieshavetheoppositeproblem;theyaremoreconcernedaboutobesity.[citationneeded]Nutritionalover
3、viewFreshvegetablesarecommoninahealthydiet.Generally,ahealthydietshouldinclude:1.Sufficientcaloriestomaintainaperson'smetabolicandactivityneeds,butnotsoexcessiveastoresultinfatstoragegreaterthanroughly30%ofbodymass.Formostpeopletherecommendeddailyallowanceofenergyis2,000calories,butit
4、dependsonage,sex,height,weight,andphysicalactivity.(seeBodyfatpercentage)2.Sufficientquantitiesoffat,includingmonounsaturatedfat,polyunsaturatedfatandsaturatedfat,withabalanceofomega-6andlong-chainomega-3lipids.Therecommendeddailyallowanceoffatis65-80grams.3.Maintenanceofagoodratiobet
5、weencarbohydratesandlipids(4:1):fourgramsofthefirstforonegramofthesecond.4.Avoidanceofexcessivesaturatedfat(20gramsrecommendedlimit,althoughthe"evidence"forthisclaimisforeverindebateafterthetestimonyofresultsprovidedbytheFraminghamHeartStudyof1948-1998)5.Avoidanceoftransfat.6.Sufficie
6、ntessentialaminoacids("completeprotein")toprovidecellularreplenishmentandtransportproteins.Allessentialaminoacidsarepresentinanimals.Aselectfewplants(suchassoyandhemp)givealltheessentialacids.Acombinationofotherplantsmayalsoprovideallessentialaminoacids(exceptriceandbeanswhichhavelimi
7、tations).7.Essentialmicronutrientssuchasvitaminsandcertainminerals.8.Avoidingdirectlypoisonous(e.g.heavymetals)andcarcinogenic(e.g.benzene)substances;9.Avoidingfoodscontaminatedbyhumanpathogens(e.g.E.coli,tapewormeggs);1.Avoidingchronichighdosesofcertainfoodsthatarebenignorbeneficiali
8、nsmal
