Prehrane s tako visoko kot nizko vsebnostjo ogljikovih hidratov so povezali z zvišano smrtnostjo, kjer je bilo minimalno tveganje opaženo pri 50-55% vnosu ogljikovih hidratov - to je rezultat, odkrit v meta-analitični študiji s preko 15 000 udeležencev, ki je bila objavljena v Lancet, eni izmed najboljših medicinskih publikacij.
Trend diete z nizko vsebnostjo ogljikovih hidratov in tveganja
Diete z nizko vsebnostjo ogljikovih hidratov, ki omejujo količino ogljikovih hidratov v prid zvišanega vnosa beljakovin ali maščob ali obeh, so priljubljena strategija hujšanja. Kljub temu je dolgoročni učinek omejevanja ogljikovih hidratov na smrtnost kontroverzen in je lahko odvisen od tega, ali so prehranski ogljikovi hidrati nadomeščeni z maščobami in beljakovinami na rastlinski ali živalski osnovi.
Diete z nizko vsebnostjo ogljikovih hidratov, ki zamenjajo ogljikove hidrate za višji vnos beljakovin ali maščob, so postale precej priljubljene zaradi svoje sposobnosti sprožitve kratkoročne izgube telesne teže, ne glede na nepopolne in konfliktne podatke, ki se tičejo dolgoročnih učinkov na zdravstveni izid.
Manj ni več in več ni preveč, srednje je ravno prav
V veliki kohorti odraslih, ki živijo v štirih različnih ZDA skupnostih, so spremljali sodelujoče v obdobju več kot dveh desetletij, in sicer prehranske vzorce v srednjih letih, ki jih zaznamuje tako nizek (<40% energije iz ogljikovih hidratov) kot visok vnos ogljikovih hidratov (>70% energije), kar so povezali z zvišano smrtnostjo in krajšo življenjsko dobo. Minimalno tveganje so opazili pri 50-55% deležu energije iz ogljikovih hidratov. Ta odkritja odsevajo U-izoblikovano zvezo med vnosom ogljikovih ogljikovih hidratov in smrtnostjo, kar je bilo potrjeno tudi s podatki iz ostalih severnoameriških, evropskih, azijskih in multinacionalnih kohort - tudi to so vključili v meta-analizo.
Diete z nizko vsebnostjo ogljikovih hidratov se nagibajo k nižjemu vnosu zelenjave, sadja in žitaric ter višjemu vnosu beljakovin živalskega izvora, kot so opazili v ARIC kohorti, ki je bila povezana z višjo smrtnostjo. Verjetno je, da so različne količine bioaktivnih prehranskih komponent v dieti z nizko vsebnostjo ogljikovih hidratov nasproti uravnoteženi dieti - kot so razvejane aminokisline, maščobne kisline, vlaknine, fitokemikalije, železo iz hema, vitamini in minerali - v to vpletene. Dolgoročni učinki prehrane z nizko vsebnostjo ogljikovih hidratov, kjer je tipično nižji vnos rastlinskih in zvišan vnos živalskih beljakovin in maščob, so bili oblikovani v hipotezo, da stimulirajo vnetne poti, biološko staranje in oksidativen stres.
Na drugi strani spektra so diete z visoko vsebnostjo ogljikovih hidratov, ki so pogoste v Aziji in ekonomsko manj naprednih narodih, kjer se nagibajo k večjemu deležu rafiniranih ogljikovih hidratov, kot je beli riž; te vrste diet lahko odsevajo nizko kakovost prehrane in rezultirajo v kronično visokem glikemičnem bremenu, ki lahko vodi do negativnih metaboličnih posledic.
Rastlinsko-osnovana prehrana je še vedno dobra izbira
Vir beljakovin in maščob, ki so v prehrani zamenjane za ogljikove hidrate, lahko opazno oblikujejo zvezo med vnosom ogljikovih hidratov in smrtnostjo. Vzorec nizkega vnosa ogljikovih hidratov, kjer je ogljikohidratno energijo zamenjala energija iz živalskih beljakovin ali maščob, je bil povezan s pojavom višjega tveganja. Vendar je bila ta zveza obratna, ko je bila ogljikohidratna energija nadomeščena z rastlinskim beljakovinami ali maščobami. Rastlinska nadomestitev je povezana s tako nižjo stopnjo kardiovaskularnih in ne-kardiovaskularnih smrti, kar indicira, da je prehranski izvor lahko pomemben dejavnik za oba vzroka smrtnosti.
Celotni članek lahko najdete tukaj: https://doi.org/10.1016/S2468-2667(18)30135-X
prevod: Tanja Topić
vir fotografij: internet
Dietary Carbohydrate Intake And Mortality - What's The Correlation?
Both high and low percentages of carbohydrate diets were associated with increased mortality, with minimal risk observed at 50–55% carbohydrate intake, a result found in a meta-analysis study with more than 15,000 subjects published in the Lancet, one of the top medical journals.
The low-crabs trend and its risks
Low carbohydrate diets, which restrict carbohydrate in favour of increased protein or fat intake, or both, are a popular weight-loss strategy. However, the long-term effect of carbohydrate restriction on mortality is controversial and could depend on whether the dietary carbohydrate is replaced by plant-based or animal-based fat and protein.
Low carbohydrate diets that exchange carbohydrates for a greater intake of protein or fat have gained substantial popularity because of their ability to induce short-term weight loss, despite incomplete and conflicting data regarding their long-term effects on health outcomes.
Less is not more and more is too much, the medial is just right
In a large cohort of adults living in four diverse US communities, with more than two decades of follow-up, mid-life dietary patterns marked by both low carbohydrate (<40% of energy from carbohydrate) and high carbohydrate (>70% of energy from carbohydrate) consumption were associated with increased mortality risk and shorter residual lifespan, with minimum risk observed with 50–55% of energy from carbohydrate. These findings reflect a U-shaped relationship between carbohydrate intake and mortality and were corroborated by data from other North American, European, Asian and multinational cohorts, combined as part of a meta-analysis.
Low carbohydrate diets have tended to result in lower intake of vegetables, fruits, and grains and increased intakes of protein from animal sources as observed in the ARIC cohort, which has been associated with higher mortality. It is likely that different amounts of bioactive dietary components in low carbohydrate versus balanced diets, such as branched-chain amino acids, fatty acids, fibre, phytochemicals, haem iron, and vitamins and minerals are involved. Long-term effects of a low carbohydrate diet with typically low plant and increased animal protein and fat consumption have been hypothesised to stimulate inflammatory pathways, biological ageing, and oxidative stress.
On the other end of the spectrum, high carbohydrate diets, which are common in Asian and less economically advantaged nations, tend to be high in refined carbohydrates, such as white rice; these types of diets might reflect poor food quality and confer a chronically high glycaemic load that can lead to negative metabolic consequences.
A plant-based diet is still the one to go for
The source of the protein and fat substituted for carbohydrates in the diet might notably modify the relationship between carbohydrate intake and mortality. Low carbohydrate dietary patterns that replaced energy from carbohydrate with energy from animal-derived protein or fat were associated with greater risk. However, this association was reversed when energy from carbohydrate was replaced with plant-derived protein or fat. Plant-based substitutions are associated with both lower cardiovascular and non-cardiovascular death, indicating that food source could be an important consideration for both causes of mortality.
The full article can be found here: https://doi.org/10.1016/S2468-2667(18)30135-X
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