Скачать или смотреть Is fructose bad for you?

In his podcast on @hubermanlab, Dr. Robert Lustig suggests that fructose is harmful because it inhibits three enzymes “necessary for normal mitochondrial function.”

AMP-Kinase
Long-chain acyl-CoA dehydrogenase 
Carnitine palmitoyltransferase I

What Lustig fails to mention is that the activation of these enzymes largely depends on the body’s energy status.

AMP-Kinase is often considered the body’s “master energy sensor.” [PMID:22436748] It’s activated during periods of low energy status, such as fasting and exercise. Intuitively, fructose would inhibit this enzyme on a cellular level because fructose provides the body with energy.

Long-chain acyl-CoA dehydrogenase and carnitine palmitoyltransferase 1 are involved in beta-oxidation, or the breakdown of fatty acids for energy.[PMID:10832093][PMID:12526798] Beta-oxidation also generally only occurs in the context of low energy status, such as during fasting and exercise. Enzymes involved in beta-oxidation are generally inhibited when the cells have sufficient energy (e.g., during or right after eating).

These enzymes are activated and inhibited by various factors — not just fructose. Ultimately, the body’s energy status drives these factors.

If you’re not consuming excessive calories (energy), then you’ll be in energy balance, and you don’t have to worry about fructose or any of these enzymes for the most part (unless you’re studying for a biochem exam).

Part 3 coming soon.