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Exercise and Fasting Linked to Brain Detox

New research paves the way for possible prevention of Alzheimer's Disease.

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Toxic proteins can ruin your brain! Doctors have known for a long time that the build-up of toxic proteins can lead to Alzheimer's Disease, Parkinson's Disease, Lou Gehrig's Disease, and other devastating neurodegenerative disorders. Until recently, no one knew how to stop the process, much less get those toxic proteins out of the brain. Sure, we knew exercise had brain-related benefits. Doctors have been recommending for a while now about an hour of exercise at least three times a week to improve the brain function for people with mild cognitive impairment and even to delay the start or slow the progress of Alzheimer’s disease.

However, until the recent release of results from a study by researchers at Harvard, no one understood exactly the mechanism of action behind the power of exercise to have this kind of an effect on the brain. Sure, exercise releases hormones which will improve mood and mental clarity. But to delay or slow down the progress of Alzheimer’s disease? On February 19, 2019, researchers with the Blavatnik Institute at Harvard Medical School released the exciting results which may explain this. The study examined the cellular effects of both fasting and vigorous exercise – both considered metabolic interventions -- which were each independently shown to improve the internal cellular disposal of so-called waste proteins.

And why is this so exciting? Because we don't have to wait for the development of a new drug! There are two things that we can all do right now, just using our body’s natural processes and without side effects. Neurodegenerative diseases such as Lou Gehrig’s Disease, Parkinson’s and Alzheimer’s disease are all linked to the excess accumulation of misfolded (mutant, toxic, or unnecessary) proteins which interfere with cellular functions. The Harvard study shows that vigorous exercise significantly increased the levels of cAMP, a chemical trigger that induces a cellular process resulting in the elimination of these excess or waste proteins. The team’s senior researcher, Alfred L. Goldberg, demonstrated through earlier research that cAMP-stimulating drugs could also precipitate the removal of these defective or toxic proteins, including those that can lead to neurodegenerative conditions. This new study shows that through either vigorous exercise or a 12-hour fast, the body can naturally induce the very same process without an introduction of any exogenous medicines or supplements.


Fasting and exercise are well-known metabolic interventions. Both can initiate the metabolic state of ketosis which is currently the subject of great interest in the research community on treatments and prevention of a variety of neurological disorders. Having a metabolic disorder is a known risk factor for developing Alzheimer’s disease. The fact that fasting and vigorous exercise are now linked to the cellular clean-up process which may be responsible for removal of excess proteins known to cause Alzheimer’s and other neurodegenerative conditions could mean that the Harvard researchers have stumbled across a biological process which might explain why metabolic disorders are such a significant risk factor for developing neurodegenerative disease in the first place.

The other thought-provoking aspect of these recent findings is the prospect that the ketogenic diet, created to mimic the fasting state without having to eschew all foods, may ultimately be a more useful long-term tool in the cellular clean up process. Patients cannot fast for more than thirty days without risking starvation. In the recent Harvard study, the benefits brought on by vigorous exercise and a 12-hour fast to induce the cellular clean up process observed in response to exercise and fasting, while exciting, were relatively short-term. The presence of the cAMP, which precipitates the removal of the waste proteins, was no longer elevated within just a few hours after the exercise and fast. The ketogenic diet, which allows for a more sustainable “fasting” state of ketosis without starvation, may be worth considering for a more robust cellular “spring cleaning” for disease treatment or prevention.

It will be interesting to see how these recent findings demonstrating how effective our own bodies can be in clearing out the toxins which are known to cause neurodegenerative diseases, through the simple expedient of fasting or vigorous exercise, will play out in future research. This study raises questions about the use of fasting, and maybe regular intermittent fasting, as a means to regularly clear these toxins to protect the brain. Further research could also be conducted into the details of exercise. The study protocol focused on biking, but likely other forms of exercise would produce similar benefits. So what kinds of exercise and how often should the exercise be prescribed for maximum therapeutic benefits? And, for those who may need a prolonged “spring cleaning,” does the ketogenic diet induce the same process by increasing levels of cAMP at the cellular level in the same way fasting does to reverse or slow the progress of Alzheimer’s disease? Hopefully, more work can be done to explore these additional possibilities to develop a targeted, long term treatment protocol without the need for any medicines or supplements to treat and maybe even prevent these crippling brain diseases.

DISCLAIMER: Nothing in this article is intended as medical advice. Anyone contemplating fasting, the ketogenic diet, a particular form of exercise, or any intervention as a treatment for an illness is urged to seek medical help from a competent medical provider trained in treatment of the underlying condition as well as the specifics of the proposed treatment or intervention. No doctor-patient relationship is created by this article, or by any responses to comments posted in this forum by Chris Palmer, M.D.

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