“Based on what I see for sale online, this has some of the highest quantity mgs of ingredients for the best possible price. Since my doc recommends this brand, I'm doubly sold.”
Prolon® 5-Day Fasting Mimicking Program
A clinically tested 5 day fasting program that delivers fasting benefits while you eat.
- A complete, pre-packaged protocol
- Backed by 20+ years of USC research
- For cellular renewal and fat loss
- Supports cellular renewal and autophagy
- Promotes healthy fat loss with muscle protection
- Boosts mental clarity and focus
- Supports metabolic and cardiometabolic health
- Renews skin and supports healthy aging
- Resets your relationship with food
- Includes everything you need pre-packaged
- Backed by 20+ years of clinical research
Prolon® 5-Day Fasting Mimicking Program
The science behind our ingredients
Prolon® 5-Day Fasting Mimicking Program
Is this right for you?
Prolon® 5-Day Fasting Mimicking Program
Is this right for you?
- 01You want fasting benefits without the hunger
Prolon delivers the cellular and metabolic benefits of prolonged fasting while letting you eat real food — making fasting accessible for everyone.
- 02You want a periodic metabolic reset
Used in cycles, Prolon supports healthy weight management, blood sugar balance, and cellular renewal. Many people use it quarterly as a reset.
- 03You're focused on healthy aging and longevity
Prolon was developed by longevity researcher Dr. Valter Longo at USC. Clinical studies show benefits for biological aging markers and cellular health.
- 04You want structure, not guesswork
Every day of the fast is pre-packaged and labeled. No calorie counting, no meal planning — just open the box and follow the program.
01
You want fasting benefits without the hunger
Prolon delivers the cellular and metabolic benefits of prolonged fasting while letting you eat real food — making fasting accessible for everyone.
02
You want a periodic metabolic reset
Used in cycles, Prolon supports healthy weight management, blood sugar balance, and cellular renewal. Many people use it quarterly as a reset.
03
You're focused on healthy aging and longevity
Prolon was developed by longevity researcher Dr. Valter Longo at USC. Clinical studies show benefits for biological aging markers and cellular health.
04
You want structure, not guesswork
Every day of the fast is pre-packaged and labeled. No calorie counting, no meal planning — just open the box and follow the program.
why we’re different
Not all supplements are created equal.
At Parsley, ‘professional grade’ means every supplement is third-party tested for quality and purity, and manufactured in NSF/USP-certified, cGMP-compliant U.S. facilities that meet FDA standards.
Our clinicians know which supplements actually move the needle — and which don't. Every formula is selected for clinical evidence, optimal bioavailability, and meaningful dosing. Not what's cheapest to manufacture. What actually works.
| Parsley Supplements | Standard Supplements | |
|---|---|---|
| Physician-Formulated | ||
| Third-Party Tested | ||
| Clinically Dosed | ||
| USA-Made | ||
| Most Bioavailable Forms |
"Many of us don’t get the nutrient density we need from our food, even if we eat healthy diets. That includes me, which is why there are certain supplements I take every day."
Dr. Robin Berzin, MD
Founder and Clinician
CUSTOMER REVIEWS
Hundreds of 5-star reviews
4.9 average rating400+ reviews
Mega Omega 3 Fish Oil
Andrea A.Verified Customer
Vitamin D3 + K2 Drops
“This product is amazing. My doctor keeps asking me again and again to remind her how my D level is so perfect. I put my husband on it too with the same results. Thank you Parsley!”
Fredda G.Verified Customer
Rebuild Clean Protein Powder
"My body started to crave this product. With battling malnourishment and malabsorption, this is a super helpful product to buy! Glad my doctor recommended it."
Mary K.W.Verified Customer
Supplement FAQ
Parsley physicians have treated over 50,000 patients using a root-cause, functional medicine approach. That depth of practice informs every ingredient we select, every dose we use, and every formula we craft. The result is a standard most supplement brands can't meet: physician-formulated, third-party tested for purity and potency, clinically dosed, and manufactured in NSF/USP-certified, cGMP-compliant U.S. facilities that meet FDA standards.
Complete your routine
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Metabolic Health
If you're dealing with weight, blood sugar, or metabolic health challenges, the most powerful thing you can do is understand what is driving them. Parsley Health physicians use advanced testing and a root-cause approach to build a plan around you — not just your symptoms.
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