Txiv maj phaub roj tau txhawb nqa ua zaub mov noj qab haus huv. Peb paub tias nws muaj qhov tseem ceeb polyunsaturated fatty acids uas tsis yog synthesized los ntawm tib neeg lub cev. Ntawd yog, lawv tsuas tuaj yeem tau txais los ntawm sab nraud. Unrefined txiv maj phaub roj yog lub hauv paus ntawm cov txiaj ntsig fatty acids, xws li lauric, oleic, stearic, caprylic, thiab ntau ntxiv. Thaum tshav kub kub, nws tsis tawm carcinogens, khaws tag nrho cov vitamins thiab amino acids, uas tso cai rau nws siv dav hauv kev ua noj.
Txawm li cas los xij, cov kws tshawb fawb Asmeskas tau qhia kom tso tseg kev siv cov roj txiv maj phaub ua ib qho analogue rau lwm cov roj zaub thiab tsiaj rog. Nws hloov tawm hais tias nws muaj yuav luag rau lub sij hawm ntau saturated fat tshaj li txiv roj roj. Saturated fats, ntawm qhov tod tes, suav hais tias tsis zoo vim tias lawv tuaj yeem nce qib roj cholesterol, ua rau muaj kev pheej hmoo ntawm kab mob plawv.
Raws li tsab xov xwm luam tawm, txiv maj phaub roj muaj 82% cov roj saturated, thaum lard muaj 39%, nqaij nyuj rog muaj 50%, thiab butter muaj 63%.
Kev tshawb fawb tau ua nyob rau xyoo 1950 tau pom qhov sib txuas ntawm cov roj saturated thiab LDL cholesterol (lub npe hu ua "phem" cholesterol). Nws tuaj yeem ua rau cov ntshav txhaws thiab ua rau mob plawv thiab mob stroke.
HDL-cholesterol, ntawm qhov tod tes, tiv thaiv kab mob plawv. Nws nqus cov cholesterol thiab thauj nws rov qab mus rau lub siab, uas ntws tawm hauv lub cev. Kev muaj cov roj (cholesterol) siab "zoo" muaj qhov cuam tshuam tsis zoo.
Lub AHA pom zoo kom hloov cov khoom noj uas muaj cov roj saturated fatty acids, nrog rau cov nqaij liab, cov zaub mov kib, thiab, alas, txiv maj phaub roj, nrog rau qhov chaw ntawm cov roj unsaturated xws li txiv ntseej, legumes, avocados, roj zaub uas tsis yog tropical (txiv ntseej, flaxseed, thiab lwm yam) .
Raws li Public Health England, ib tug txiv neej hnub nyoog nruab nrab yuav tsum tsis txhob noj ntau tshaj 30 grams ntawm saturated rog ib hnub twg, thiab ib tug poj niam yuav tsum tsis txhob ntau tshaj 20 grams. AHA pom zoo kom txo cov roj saturated rau 5-6% ntawm tag nrho cov calories, uas yog kwv yees li 13 grams rau 2000 calorie noj txhua hnub.