Fasting: Best-Kept Secret or Unnecessary Fad?
July 15, 2021
Rhya Pachin, RDN, LDN, CLT

Hello again, Rhya Pachin here - your friendly neighborhood Registered Dietitian + Functional Nutritionist. I’ve read the accumulating research on the benefits of fasting for metabolism, inflammation reduction, and cellular renewal/anti-aging. I've also had several clients who were looking for the best possible way to lose stubborn weight in a safe, sustainable way. So…I took one for the team (suckered my husband into doing it with me) and finally took the plunge so that I’d know how to guide clients better and experience the benefits for myself. So here’s (maybe more than) everything you wanted to know about fasting!


Fasting allows the body time to heal and repair, and there are several ways to reap its benefits.


1) Fasting overnight:

12+ hours of fasting allows the body to rest and repair without having to supply extra energy to digestion.

Yes, 12 hours for overnight fasting is usually sufficient for general restoration and repair. Is a longer overnight fast more beneficial? Maybe. See point #2.


2) Intermittent or extended overnight fasting:

The research mostly says yes, intermittent fasting (fasting for additional hours per day or days per week) can improve insulin resistance and may support healthy weight loss.

These benefits have been shown more consistently in men. However, I have worked with several women who damaged their metabolism from fasting for too long of a period over too many months due to extreme caloric restriction combined with excessive stress. So more is not always better; 12-14 hours is a good window to start with. If you workout at 5am, it’s important to fuel the body within 1-2 hours afterwards. Waiting too long may negatively impact metabolism so don’t get carried away with fasting when it doesn’t make sense!


3) Fasting Mimicking diet (FMD):

While a short term water fast can support weight loss, it is of course not enjoyable or practical. Fortunately, recent studies at UCLA showed how a low caloric intake which mimics fasting (ie does not trigger nutrient-sensing pathways) can produce similar effects. This is what I tried! I used a product called Prolon, which was much easier than figuring out the macro ratios and of protein, carbs and fat on my own and weighing out small, precise amounts of food.


Here were my results (updated I’ve kept off 5 of the 8 lbs I lost and according to my InBody

measurements it was definitely body fat loss which is pretty cool!)

Some tips I can offer if you try a Fasting Mimicking Diet

If you have any further questions, feel free to reach out via Instagram @carolinafunctionalnutrition or book a jumpstart call.

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About the Author

Rhya Pachin is a licensed dietitian nutritionist who employs an "integrative" approach to support overall health rather than addressing just one symptom. As a certified LEAP therapist, she designs and supervises custom elimination diets. Her focus areas include gastrointestinal conditions like IBS and IBD, autoimmune diseases such as rheumatoid arthritis and Hashimoto's, persistent weight issues, food sensitivities, and chronic inflammatory conditions in both adults and children.

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