What Is mTOR & Does It Cause Cancer?

Mammalian Target of Rapamycin or mTOR is nutrient sensing protein kinase and an important factor for health and longevity.

mTOR is the body’s main growth pathway that promotes muscle growth, cell replication, and anabolism. There are two mTOR complexes mTORC1 and mTORC2.

Some people fear mTOR, as is linked to some cancers under certain circumstances as mTOR is anabolic. This is usually when there is mTOR dysfunction or disease already present. Over stimulation of mTOR in some species can shorten lifespan.


mTOR is inhibited and AMPK is activated in times of nutrient scarcity.

Fasting lowers glucose, insulin, and suppresses mTOR while raising AMPK.

This is the best and most effective method of inhibiting mTOR. This also stimulates autophagy (breaking down of old damaged cells) and promotes ketosis.

Calorie restriction lowers mTOR and promotes autophagy

Exercise inhibits mTORC1 in liver and fat cells, but not muscle cells

Curcumin, Resveratrol, Rhodiola rosea and metformin inhibit mTOR


Being in a fed state with nutrient abundance (protein, carbohydrates, fats) activates mTOR as nutrients need to be sent/partitioned to the correct locations in the body. This is the main way mTOR is activated

Glucose, insulin, IGF-1 all promote mTOR activation.

Amino acids (particularly leucine) promote mTORC1 activity, without affecting mTORC2 activity

Mechanical stimuli from resistance exercise, increases the levels of mTORC1

Testosterone and androgens can also promote mTOR activation and induce muscle hypertrophy.


mTOR isn’t good or bad, it is about balance. Too much mTOR all the time is not a good idea. Not enough mTOR will affect lean muscle mass and cellular repair

Dr Sara Pugh - Busy Superhuman

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Hello, I’m Sara and I am a biochemist, neurotherapist and hypnotist. My stories and articles are about human biology, improving your brain and supplements