Should I buy supplements on Amazon?
Usually, no. For potency, purity, and safety, I recommend practitioner-grade supplements purchased directly from the manufacturer or an authorized dispensary. Large marketplaces mix third-party sellers, so chain-of-custody and storage standards are harder to verify. If you do buy there, choose third-party verified products and the brand’s own storefront to avoid counterfeits and poorly stored items.
Why I rarely recommend big-marketplace supplements
As a functional medicine practitioner, my first priority is that what you take is exactly what the label says, stored the way the label requires. On large marketplaces, multiple third-party sellers can list the same product, which makes it hard to confirm handling, lot numbers, or whether a product is expired or relabeled.
The FDA does not approve supplements before they are sold, which means enforcement is mostly after problems are reported. That gap increases the importance of trusted sourcing, especially for people who are already feeling dismissed and want clear answers.
What can go wrong in big marketplaces
At Dr. Kenny’s clinic we see three recurring risks when patients source supplements from open marketplaces like Amazon:
- Potency misses and counterfeits. Independent testing has repeatedly found products from unfamiliar marketplace brands that are under-potent or mislabeled. That can stall progress or, in the worst case, be unsafe.
- Poor storage for heat-sensitive nutrients. Probiotics and certain oils lose potency with heat, oxygen, or time. Without tight control of shipping and storage, you can receive something weaker than promised, even if it’s a high-quality brand and product.
- Hidden or undeclared ingredients. Some online products have been flagged for containing pharmaceutical drugs or unlisted substances, which can interact with medications.
A safer way to source supplements
As a functional medicine practitioner, I use a simple rule set so supplements help rather than complicate care.
- Choose third-party verified brands. Look for USP or NSF marks that confirm identity and contents. USP explains exactly what its Verified Mark means for you.
- Buy from authorized channels. Prefer the manufacturer’s website or your practitioner’s dispensary so chain-of-custody is clear. Dr. Kenny offers discounts to all of his patients to incentivize using high-quality, well-researched brands and supplements to streamline treatment efficacy.
- Use my 3T method for strategic supplementation. At Dr. Kenny’s clinic we make supplements Targeted, Therapeutic, and Temporary, so they solve problems rather than becoming a never-ending “green pharmacy.”
- Mind the basics. Check lot and expiration dates, follow storage directions, and track how you feel so we can adjust quickly.
When an Amazon purchase might be reasonable
If the brand sells directly on its official storefront, if the listing shows a recognized third-party verification mark, and if the product is not heat-sensitive, you may be fine for short-term convenience. Still, for most patients seeking root-cause care, authorized sources remain the better long-term strategy for quality and consistency.
Additional Resources:
- For a step-by-step breakdown on making your supplements count, explore The 3T Method for Strategic Supplementation or watch it on Youtube
- A 2024 FDA consumer Q&A confirms supplements are not FDA-approved before marketing, so oversight is largely post-market.
Industry testing published by NOW found many marketplace products under-delivered on label potency for nutrients like CoQ10 and quercetin.
Ready to simplify your stack and source safely?
Answered by Dr. Kenny Mittelstadt, DACM, DC, IFMCP
Certified functional medicine practitioner specializing in advanced lab testing and personalized healing protocols to uncover root causes of health roadblocks.