Many medical foods are designed to treat inborn errors of metabolism such as phenylketonuria (PKU), where the body cannot metabolize the amino acid phenylalanine or maple syrup urine disease, where branched-chain amino acids cannot be metabolized. Medical foods have also been developed for Crohn’s disease, ulcerative colitis, gastroesophageal reflus disease, chronic intestinal pseudo-obstruction, insomnia, ADHD and inherited diseases of amino acids and organic acids.
There are three main types of medical foods. The first are products which omit the substance which must be avoided but otherwise contain a full complement of nutrients, such as Lofenalac, Ketonex-2 and Propimex. The second includes modular products such as GlutarAde and Foltx. The third type includes low-protein foods, used to meet energy requirements in patients with inborn errors of metabolism that need protein restricted diets. Medical foods cannot be labeled or marketed for diseases for which can be treated with regular modifications to diet, such as diabetes, obesity or nutrient deficiencies like scurvy or pellagra.
The US Orphan Drug Act defines medical food as “a food which is formulated to be consumed or administered enterally under the supervision of a physician and which is intended for the specific dietary management of a disease or condition for which distinctive nutritional requirements, based on recognized scientific principles, are established by medical evaluation”, from (Section 5(b) of Orphan Drug Act (21 U.S.C. 360ee (b) (3)).
In Canada, food that is specially processed or formulated to meet the particular requirements of a person with a physical or physiological condition by controlled intake to have a particular effect is defined as “food for special dietary use” under Food and Drug Regulations (9.9 Foods for Special Dietary Use [Division 24, FDR]).
"Foods for special medical purposes" are regulated in the European Union Commission Directive 1999/21/EC. New compositional and labeling rules by Commission delegated Regulation 2016/128 were adopted on 25 September 2015 and set to be applied on 22 February 2019. Foods for special medical purposes are defined as foods intended for exclusive or partial feeding, for dietary management, under medical supervision for individuals with certain diseases, disorders or medical conditions when nutritional requirements cannot be met by normal foods.
Codex Alimentarius was created by FAO and WHO to develop food standards and guidelines in 1963. The Codex Committee on Foods for Special Dietary Uses developed a standard for labeling medical foods using the term “foods for special medical purposes” in 1987. It was determined that labels should include essential information for health professionals. Some required provisions include energy value, content of protein, fat, carbohydrates, vitamins and minerals and amino acids or essential fatty acids if applicable. In some cases osmolality and acid-base balance must be on the label.
In the US medical foods are designed to be used under physician supervision, however they are not allowed to be labeled Rx only and some medical products available online do not need physician approval. Nevertheless, many products are marketed as prescription only medical foods, such as Metanx to treat diabetic nerve damage.
Medical foods are not classified as drugs and do not require clinical testing for efficacy, premarket review and FDA approval. The ingredients are required to be FDA Generally Recognized as Safe.
Products excluded from medical foods designation by US FDA
Diabetes mellitus (DM)
The US FDA does not consider DM to be a disease for which medical foods can be labeled or marketed due the following lines of reasoning:
“There are no distinctive nutritional requirements associated with the management of diabetes mellitus” and “A regular diet can be modified to meet the needs of an individual affected by DM ( along with appropriate drug therapy if necessary)”.
“Under 21 CFR 101.9(j)(8)(ii), a medical food must be intended for a patient who has a limited or impaired capacity to ingest, digest, absorb, or metabolize ordinary foodstuffs or certain nutrients or who has other special medically determined nutrient requirements, the dietary management of which cannot be achieved by the modification of the normal diet alone.”
The FDA’s stance is perceived as a reaction to companies selling dietary supplements disguised as medical foods.
Frequently Asked Questions About Medical Foods; Second Edition Guidance for Industry
Top Medical foods companies | VentureRadar
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