Swapping processed meats and seafood for plant-based foods may increase folate levels in the blood, while swapping fish and mixed meats for refined grains or plant proteins may decrease vitamin B12...
Mechanism
Synthesis from 1 study
Switching to certain plant foods can give you more folate because those foods naturally contain it. But vitamin B12 only comes from animals or fortified products, so if you replace meat and fish with plain plant foods that don’t have added B12, your body gets less of it and your levels go down.
Most probable mechanism
When you swap out certain animal foods for plant foods, you change how much folate and vitamin B12 your body gets. Some plant foods have more folate, so your folate levels go up. But vitamin B12 only comes from animal sources or fortified foods, so if you replace animal foods with plain plant foods that don’t have added B12, your body gets less of it and levels drop.
Consumption of plant-based alternatives rich in naturally occurring folate increases dietary intake of this water-soluble vitamin.
Increased dietary folate leads to higher absorption in the small intestine via specific transporters, elevating circulating folate levels.
Replacement of fish and meat with refined grains or unfortified plant proteins reduces intake of preformed vitamin B12, which is not synthesized by plants.
Reduced intake of vitamin B12 leads to lower absorption in the ileum, where intrinsic factor binds the vitamin for uptake, resulting in declining serum B12 levels over time.
Evidence from Studies
Supporting (1)
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Substituting animal protein foods with plant protein foods influences vitamin B12 and folate statuses in a multiethnic Asian population
Contradicting (0)
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