Is fasting all it’s cracked up to be?

In recent years fasting has become trendy. We all have an idea of how fasting will affect us, whether we’ll be curled in a ball with hunger pangs or in the opposite extreme floating down a beach in Northern California, light as a feather with perfect, glowing skin.

Our members understand that the truth about fasting probably lies somewhere in between, but there is a lot of interest in the science behind how fasting affects the body and specifically hormone levels such as HGH (Human Growth Hormone).

For some added clarity, we turned to a partner of ours, Dr. Peter Attia, who specializes in the applied science of longevity.

Studies have reported intermittent fasting can dramatically increase HGH levels. Is that true?

“Fasting does affect your hormone levels,” notes Dr. Attia. “Specifically IGF (goes down), testosterone (usually down), and thyroid function often deteriorates.” But, Dr. Attia believes, “it’s hard to know what happens exactly with HGH, since it’s such a pulsatile (burst-like) hormone and not helpful to measure directly.” Or in other words, the jury is still out on how fasting impacts HGH specifically and whether any impact would be beneficial.

Also Dr. Attia doesn’t believe that cutting calories and losing belly weight fast are necessarily the only or even main benefits of fasting. Yes, intermittent fasting can have these effects, but the benefit of fasting is “more likely related to enhanced autophagy (the process of cellular self-cleansing that breaks down/recycles damaged molecules and cellular organelles), reduced inflammation, glycogen depletion, and the psychological benefits of learning that you can thrive without being tethered to your next meal or snack,” Attia says.

There are many ways to fast, including juice fasts or broth fasts, but fasting in its purest form is “a water-only fast that can be done under medical supervision with great safety and efficacy,” Attia notes. There are of course some hazards to fasting including, “electrolyte imbalance,” especially “sodium and magnesium depletion, and orthostasis ( a dangerous blood pressure drop when standing up).” So always consult your doctor, whether fasting or engaging in a hypocaloric (consume fewer calories than you burn) diet, which “for periods of time can also have similar benefits,” Attia says.

Fasting should be seriously considered as part of a balanced approach to optimal health. However, there are a variety of other strategies that might be even better suited to you. We recommend discussing your options with your healthcare provider to find the best fit.

For additional recommendations or access to our referral network, contact us here.

Dr. Peter Attia is the founder of Attia Medical, PC, a medical practice with offices in San Diego and New York City, focusing on the applied science of longevity. Peter earned his M.D. from Stanford University and holds a B.Sc. in mechanical engineering and applied mathematics.


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