Food supplements in context
Food supplements are one of several types of product a patient may take. Understanding the difference between food supplements and medicinal products allows informed decision-making on the right product for the patient’s circumstances.
Products can be divided into those regulated as foods and those regulated as medicines or medical products.
Food products
The Food Standards Agency regulates food products. Food supplements must conform to nutrition legislation. Food products can be marketed without notifying a regulator or providing any evidence of quality.
Manufacturers of food products are allowed to make nutritional or health claims. They are not allowed to make claims to treat or prevent any disease or condition. The Advertising Standards Agency provides further information about medicinal claims.
Food supplements
Food supplements are defined by the Food Supplements (England) Regulations (2003) as ‘any food, the purpose of which is to supplement the normal diet, and which is a concentrated source of a vitamin or mineral or other substance with a nutritional or physiological effect, alone or in combination and is sold in dose form’.
More information about nutrition law and specific guidance on food supplement regulation can be found on the GOV.UK website.
Foods for Special Medical Purposes
Foods for special medical purposes (FSMPs) are for patients whose nutritional needs cannot be met by ordinary foods due to a particular disease or condition. FSMPs must be used under the supervision of a healthcare professional.
FSMPs are regulated as foods, but the manufacturer must notify the ‘competent authority’ when an FSMP is placed on the market. In England, this is the Department of Health and Social Care (DHSC). The DHSC does not regulate FSMPs, but notification allows Trading Standards to undertake monitoring activities, such as label reviews or product sampling, for enforcement purposes.
Medical Products
The Medicines and Healthcare Products Regulatory Agency (MHRA) regulates medicines, traditional herbal medicinal products, and medical devices. Claims about treating or preventing medical conditions are permitted. Products must be licensed or registered before being placed on the market and are more closely regulated than foods.
Medicines
Medicines are substances or combinations of substances that can be used to treat or prevent disease by exerting a pharmacological, immunological or metabolic action. A substance used to make a medical diagnosis may also be a medicine.
Our article Explaining the licensed status of medicines provides more information.
Traditional Herbal Medicinal Products
A Traditional Herbal Medicinal Product (THMP) in the UK is a herbal medicine registered under the Traditional Herbal Registration (THR) scheme. These are for treating minor conditions based on traditional use. They do not need to provide evidence of efficacy. However, they do need to prove quality and safety, and provide patient information.
For the full definition, see the Human Medicines Regulations 2012.
Medical devices
Products that rely solely on physical or mechanical action may be marketed as medical devices.
Borderline Substances
The MHRA is responsible for deciding the regulatory status of products. It uses the term ‘borderline substance’ when the categorisation of an item as a medicine, food, device, or something else is initially unclear.
The British National Formulary also uses ‘borderline substances’ to refer to products that are not medicines or medical devices but may be prescribed on NHS prescription. Some, but not all, of the products on the list are FSMPs.
Identifying food supplements
Food supplements may include the words ‘food supplement’ on their label. However, they do not have further markings such as licence numbers or symbols. FSMPs will usually include information about their purpose on the label.
Licensed medicines have a product licence (PL) or marketing authorisation (MA) number on the packaging. This is in the format PL or PLGBXXXX/XXXX.
Traditional Herbal Registered (THR) products have a THR number and may have a certification symbol. Medical devices will have a CE or UKCA mark.
Safety, efficacy, and quality
The MHRA and FSA require manufacturers to issue recalls and alerts if a defective product is identified. However, there are important differences in how medical products and food products are regulated.
Differences in safety and efficacy assurance
Requirements differ between medicines, herbal products, and medical devices. All require proactive assurance of safety and efficacy.
Food supplements and FSMPs
Food manufacturers are not required to prove the safety or efficacy of their products before placing them on the market. Food supplements and FSMPs are not monitored proactively once they are on the market. However, safety concerns should be reported to the Food Standards Agency.
Medicines
Medicines cannot be placed on the market until the MHRA has granted a Marketing Authorisation (Product Licence). The Marketing Authorisation Holder must prove that the medicine is safe and effective for its intended uses.
Licensed medicines are continuously monitored for safety and efficacy. If new evidence indicates that the balance between risks and benefits of the medicine is unacceptable, the product may be withdrawn from the market.
Unlicensed medicines (‘specials’) are supplied to meet the special clinical needs of individual patients. They are not monitored in the same way as licensed medicines, but the MHRA still regulates their importation, manufacture and supply.
Our articles about Understanding unlicensed medicines provide more information.
Traditional Herbal Medicinal Products
Traditional Herbal Medicinal Products (THMPs) must meet safety, quality, and patient information standards before they can be registered and placed on the market. However, they do not need to meet efficacy standards.
The safety of THMPs is monitored the same way as medicines.
Medical devices
Medical devices must be registered with the MHRA and conform to the requirements of relevant legislation for safety before they can be marketed. For some devices, the manufacturer can self-declare conformity, but for other devices this must be done by a third party.
The MHRA monitors the safety of medical devices.
Differences in manufacturing and testing
Manufacturers of food supplements are subject to the manufacturing standards for foods. Manufacturers of medical products must adhere to MHRA standards, which are more stringent.
Food supplements and FSMPs
The food product manufacturing standards ensure that the product will not harm the consumer, and it is of a standard consumers would expect. Labelling must not be misleading or deliberately false.
Food supplements are not required to be manufactured to the more stringent standards of medicines. Therefore, there may be significant variations in quantity of ingredients between batches and within the same batch. Undeclared ingredients may also be present.
Some food supplement manufacturers may follow medicines manufacturing quality principles voluntarily, although they will not be inspected by an outside authority. However, others do not, and it can be difficult to obtain reliable information about product quality.
Consequently, laboratory testing, either by the manufacturer or the purchaser, is of limited value. This is because:
- the sample taken may not be representative of the product
- the laboratory used may not be appropriately accredited
The existence of a Certificate of Analysis, or a document purporting to be one, does not prove suitability for use. Our article Evaluating the quality of UK Manufactured Specials provides more information about certificates.
It can therefore be difficult to be certain of the quality of a food supplement even after extensive investigation.
Medicines, THMPs, and medical devices
Licensed and unlicensed medicines, and THMPs sold in the UK must be made following Good Manufacturing Practice (GMP) standards. Medical devices must conform to medical devices regulations. These standards require clearly defined processes to assure quality and a rigorous programme of checking and testing. This ensures that there is minimal variation within and between batches, and that the product’s content matches the label.
The MHRA regularly inspects and licenses all medicine and THMP manufacturing sites in the UK to ensure they comply with GMP. Medical device manufacturing sites are audited by Notified Bodies.
Product and patient information
Marketing Authorisation Holders of medicines and traditional herbal medicinal products must provide two forms of product information:
- a Patient Information Leaflet (PIL)
- a Summary of Product Characteristics (SmPC) aimed at healthcare professionals
Food supplement manufacturers are not required to provide product information, although some information may be available on the packaging or the manufacturer’s website. Manufacturers must not make medicinal claims on labels or leaflets.
Report food supplement product information that imitates that of a medicine by sending an email to the MHRA’s Medicines Borderline Section.
Using food supplements safely
For advice on using food supplements for medicinal purposes safely, see our article:
Our article series on Advising on complementary products and conventional medicines provides advice on dealing with food supplements and complementary products purchased by patients.