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Biochemical Pathway

β-Oxidation

Fatty acid → acetyl-CoA inside mitochondria; carnitine shuttle

β-oxidation is how your body burns fat for fuel. Each pass through the spiral chops two carbons off the end of a fatty acid, releasing acetyl-CoA (which feeds the TCA cycle) plus NADH and FADH₂ (which feed the electron transport chain). It happens inside mitochondria — but long fatty acids can't cross the mitochondrial membrane on their own, so L-carnitine acts as a shuttle, escorting them across. Carnitine deficiency or B2 deficiency slows fat oxidation, which is why endurance athletes are interested in carnitine supplementation and why low-B2 vegetarians sometimes report 'low-energy' on low-carb diets.

Primary cofactors

The load-bearing nutrients — if these are deficient, this pathway slows down. Click any to see daily targets, food sources, and supplements that supply it.

Additional cofactors

Nutrients that contribute to this pathway but aren’t the single load-bearing inputs.

Related pathways

Pathways that share a load-bearing cofactor with this one.