Great
Based on 95 reviews
Z-STACK4.1Honesty, pricing, process and quality scores appear once 5 customers have rated them.
Zelenko Labs, built on the legacy of Dr. Vladimir Zelenko, creates products with purpose, precision, and integrity. Every formulation is made with high-quality ingredients and consistent standards, so you can feel confident in what you’re using. Thoughtful, reliable, and principled — Zelenko Labs products are made for people who care about quality.Our All American customer service team is here to help Monday through Friday, 9 AM to 5 PM EST — just give us a call at 1-800-ZELENKO (1-800-935-3656) or email our team at [email protected]
Z-STACK (zstacklife.com) has 95 customer reviews on Folks Told, with an average rating of 4.1 out of 5.
Showing 71 reviews with 5 stars · Clear filters
Janis
I have been a satisfied customer for years and I'm impressed with the products as well as the customer service. I take the Z-Detox which offers a great combination on ingredients, which I would otherwise be taking separately. I had great respect for Dr. Zelenko and I'm grateful that the company has carried on since he passed away.
K V.
Fantastic product! Use the Z-Stack and Z-Night everyday. Will not go without them. Been using both products currently. Started Z-Stack went it first came out and added the Z-Night when they created the bundle buy option.
Jessy G.
ZStack has made me feel more awake in the mornings and has kept me from getting sick. I've been using ZStack for 3 years and I love it!!! Thank you Dr. Z!!
Kathy G.
I am a new subscriber. I saw this product and I had watched Dr. Zelenko on a few podcasts. At the time I could not afford the product but I did not forget the results of using the product and the quality of the product and wanted to see the results.
Kendra O.
I began taking my Zstack soon after Covid began. I am 77 and healthy but would get the yearly flu and occasional colds. Since starting my Zstack, I have not been sick with anything. My doctor is amazed and I shared the reason why....my Zstack. Thank YOU for this wonderful totally effective supplement!!!
Sandra M.
I will be starting my 3rd bottle of Z-Stack. Previously I had used another company's Quercetin product. Changed over to Z-Stack because of the additional additives of Vit. C, D3 and Zinc. I work in a restaurant and love the protection in gives me. Highly recommend.
Beverly
I have been taking Z-stack ever since 2019. I am 68 years old and have not had to go to the doctor all this time. I know that this product has worked for me! It’s awesome! No sickness at all! All these years! 1 a day has kept the doctor away! 😊! Try this! You will not be disappointed!
Reply from Z-STACKSep 9, 2026
Thank you Beverly!
Mary H.
We have been taking Z-Stack since right after Covid. We had one mile case of covid a few years back, Otherwise, we have been very healthy. We feel much safer being out in public by taking our Z-Stack and have had no colds or other viruses for years.
Reply from Z-STACKSep 9, 2026
Thank you Mary!
