Dietary supplements are available from a wide range of suppliers including health food stores, chemists and pharmacies, professional health care providers and online stores.
The quality of dietary supplements varies enormously depending on the supplier, the supplement, the ingredients and manufacturing process.
If you are contemplating taking dietary supplements, you should seek advice from a GP, pharmacist or dietitian. The British Dietetic Association has information about qualified dietitians in the UK.
For children and adults who are not eating a varied and sufficient diet, for example, avoiding food groups, or eating a very restricted diet, a dietitian can help by assessing dietary intake and advising on testing and supplementation where necessary.
All professionals involved with adults and children on the autism spectrum should watch for potential nutritional problems particularly if their diets are restricted.
There are no formal, internationally validated registered qualifications for most people who provide dietary supplements.
However, in the UK, the quality of dietary supplements is regulated by the Medicines and Healthcare Products Regulatory Agency, if they ‘contain a pharmacologically active substance or make medicinal claims (claims to treat or prevent disease, or to interfere with the normal operation of a physiological function of the human body) ...’
In the UK certain supplements are considered to be foods and will therefore be regulated under general food laws by the Food Standards Agency and Department of Health. Others will be regulated as a medicine by the Medicines and Healthcare Regulatory Agency (MHRA).
All herbal medicines placed on the UK market must have a Traditional Herbal Registration (THR)10 or a marketing authorisation (previously known as a product licence). The MHRA now defines individual herbal medicines as either registered traditional herbal medicines or licensed herbal medicines.
In the USA dietary supplements are not classed as drugs, but the Food and Drug Administration is responsible for taking action against any unsafe dietary supplement product after it reaches the market.