GMP vs FDA: What Brands Should Know

GMP, or Good Manufacturing Practices, is a system of process controls. For dietary supplements in the US, it is codified in 21 CFR Part 111. It covers facility design, equipment cleaning, raw material identity testing, batch records, deviation handling, and finished product testing. A GMP-certified facility undergoes regular third-party audits. The certificate is not a one-time badge. It requires annual surveillance and re-certification.

When you see 'GMP' on a supplement label, it means the manufacturer has documented procedures to prevent mix-ups, contamination, and incorrect potency. It does not mean the product is effective or safe for every consumer. It means the process is controlled. For brands, this is the baseline. Without GMP, you cannot legally sell supplements in the US, EU, or UK. Retailers like Amazon, Walmart, and Boots will request a GMP certificate before onboarding.

The FDA does not certify dietary supplement manufacturers. It registers them. A facility registration is a notification that a company manufactures, processes, packs, or holds dietary supplements for US distribution. It is mandatory under the Bioterrorism Act and the Dietary Supplement Health and Education Act. Registration is free and does not involve an inspection or approval. Any facility can register.

The FDA conducts inspections, but they are not pre-approval. An 'FDA-registered facility' simply means the company has filed its paperwork. It does not mean the FDA has reviewed the plant's quality systems. Some brands use 'FDA-registered' to imply approval. That is misleading and can trigger warning letters. The correct claim is 'manufactured in an FDA-registered facility that follows GMP.' Even then, the FDA does not endorse the product.

Ask for three documents: a current GMP certificate, the last FDA inspection report (Form 483 if any), and a certificate of analysis for a finished product. The GMP certificate should be issued by a recognised third party such as NSF, NPA, or SGS. Check the expiry date. A certificate older than 12 months without a surveillance audit is a red flag. The FDA inspection report shows whether the facility has unresolved observations.

Request a sample batch record. It should show raw material lot numbers, weights, in-process checks, and final testing. If the manufacturer refuses, walk away. For export to the EU, the facility must also meet EU GMP Annex 1 and register with the local competent authority. For the Middle East, halal certification from a recognised body is often required. EUPHM holds GMP, ISO 22000, HACCP, and halal certificates. We provide batch records and CoAs with every production run.

Every batch produced under GMP is tested against a written specification before release. At minimum, incoming raw materials are tested for identity by FTIR or HPLC, and finished products are tested for potency (assay of active markers), microbial limits (total aerobic count, yeast and mould, E. coli, Salmonella, Staphylococcus aureus), heavy metals (lead, arsenic, cadmium, mercury by ICP-MS), and disintegration time for tablets and capsules. Additional tests such as dissolution, moisture content, or pesticide residues are added when the dosage form or market requires them. Testing is typically performed in-house and confirmed by an accredited third-party laboratory for release.

The certificate of analysis (COA) is the central batch document. A complete COA should list the product name and batch number, the specification and test method for each parameter, the result obtained, and a pass or fail statement against the specification. It should be signed by the quality control manager and dated. For export markets, the COA is often requested by customs brokers and by retail buyers during vendor onboarding. A COA that shows only potency and a generic microbial statement, without method references or heavy-metal results, is a signal to ask for the full batch record.

Retention samples are kept for every batch, typically for the shelf life of the product plus one year, stored under the same conditions as the commercial stock. These samples allow a manufacturer to re-test a batch if a customer complaint or stability question arises. Stability protocols usually follow a real-time study at 25°C and 60% relative humidity, with testing points at 0, 3, 6, 12, 18, and 24 months, and accelerated conditions at 40°C and 75% relative humidity for 6 months. The resulting data supports the expiry date printed on the label and is part of the documentation a brand should keep on file.

Packaging format affects both line setup and retail channel. Common options for dietary supplements include high-density polyethylene (HDPE) bottles with induction seals and child-resistant caps, blister packs for unit-dose tablets and capsules, stick packs for single-serve powders, and sachets for larger powder doses. Bottle sizes typically range from 60 cc to 500 cc, with label dimensions matched to the container. For Amazon and other e-commerce channels, the manufacturer should be able to apply the FNSKU label and pack to the marketplace's requirements, including poly-bagging and suffocation warning labels where applicable.

The FDA dietary supplement label has required elements that differ from conventional food labels. These include the statement of identity, net quantity of contents, a Supplement Facts panel with serving size and percent daily value, a list of ingredients by common name, and the name and place of business of the manufacturer, packer, or distributor. Structure-function claims are permitted but must carry the disclaimer that the statement has not been evaluated by the FDA and that the product is not intended to diagnose, treat, cure, or prevent any disease. The manufacturer can print and apply labels, but the brand owner remains responsible for claim substantiation.

Lot and expiry coding are applied at the filling line, usually by inkjet or laser, and must remain legible through the product's shelf life. Carton specifications typically include a stated corrugated board grade, a maximum gross weight per carton (often 10 to 15 kg for manual handling), and a case pack count that matches the retailer's preferred unit. Pallet configurations are agreed in advance: standard pallet dimensions, layers per pallet, and stretch-wrap or corner-board requirements. These details prevent chargebacks from retail distribution centres and keep unloading times predictable.

The production timeline starts with the sample. For a new formula, sample lead time is typically 7 to 10 working days after the formula and packaging specification are agreed. Sample approval is a formal step: the brand should confirm the formula, the dosage form, the fill weight, the label artwork, and the packaging components in writing before mass production is scheduled. Changes after this point, particularly to the formula or the label, usually require a new sample round and can add one to two weeks to the schedule.

Mass production typically runs 20 to 35 working days after sample approval, depending on the dosage form and whether packaging components are in stock. Capsules and tablets are faster to schedule than powders that require custom flavouring or stick-pack filling. The manufacturer should provide a production schedule with a confirmed ship date. Air freight is used for pilot runs and for time-sensitive launches, with transit times of roughly 5 to 10 days door to door depending on the destination and customs clearance. Sea freight is used for full-container orders, with transit times of 25 to 40 days to major ports in Europe and North America.

Incoterms should be agreed before the purchase order is issued. EXW places collection and export clearance on the buyer; FOB places loading on board at the named Chinese port on the manufacturer; DDP places delivery and import duty on the manufacturer and is common for e-commerce sellers shipping to an Amazon fulfilment centre. The document pack usually includes the commercial invoice, packing list, bill of lading or air waybill, certificate of analysis, material safety data sheet (MSDS) for the finished product or key ingredients, and a free-sale certificate. Phytosanitary certificates apply only where botanical raw materials are regulated by the destination country.