EtichettaJust like regular food, supplements must have a label that mentions every single ingredient in a clear and transparent way. The labelling requirements for food supplements on the EU market are established by Directive 2002/46 / EC (legislation on food supplements transposed also in Italy) and, as specified on the website of the European Food Safety Agency (EFSA), includes:
- The names of the categories of nutrients or substances used within the product formula or an indication of nutrients or substances source;
- the portion of the product recommended for daily consumption;
- the warning not to exceed the daily dose defined as recommendable;
- the recommendation not to use dietary supplements as a substitute for a varied diet;
- the recommendation to keep products out of the reach of children.
Product CertificationA certified formula implies that the product has been tested to assess its efficacy (which includes metabolic efficiency, functional capacity and safety) on specific physiological targets.To ensure its effectiveness, food supplements usually leverage on the deductive method: the formula is composed of ingredients that have been individually tested for tolerance, safety, and efficacy; then their mix (the formula) combining them is tested, safe, and effective.This approach, while logically sound, has inherent limitations:
- ingredients can interact with each other, altering their individual biochemicals effectiveness.
- ingredients can be conveyed in a way (powder, gel, water, nanocapsules, liposomes, etc..) that influences their efficacy and that is not always the same used by the raw material supplier for the efficacy and safety test;
- the same ingredients do not necessarily have the same efficacy. As an example, not all blueberry extracts have the same anti-oxidant capacity; not all forms of magnesium have the same neurological properties.
It’s important to know that a prospective clinical trial involves approval by an ethics committee, which ensures that the study protocol and how it is carried out are thoroughly monitored.A food supplement with a tested formula , in laboratory or in vivo, and a specific physiological target is classified as a Nutraceutical is a syncratic neologism from "nutrition" and "pharmaceutical" coined by Stephen de Felice in 1989. Nutraceuticals are those nutrients contained in foods that have beneficial effects on health, their effectiveness has been proven by clinical trials.. The choice of a food supplement goes through the evaluation of elements such as transparent label, certification, bio-accessibility and bio-availability, synergies and antagonisms, production of the product, etc.
As for foods, the label of dietary supplements must report every single ingredient, indicating its nature, the daily recommended dosage and warnings for a correct usage
Bioaccessibility and BioavailabilityA good food supplement is designed to provide a useful contribution to human metabolism and to different physiological targets. For this to be possible, it is essential to take into account two characteristics: bioaccessibility and bioavailability.Bioaccessibility represents that fraction of the food product useful for metabolic and nutritional purposes. In practice, it is the part that is released by digestion to be absorbed in the intestine.Bioavailability, on the other hand, is just that percentage of nutrients that can be absorbed by the intestine and entering the bloodstream to be used, in the correct form and in sufficient quantity, where it is needed. For example, it is absolutely useless to take high amounts of a nutrient when its bioavailability is low, because our body will “throw it away”. Evaluating whether the nutrients contained in a certain supplement are more or less bioavailable is a task for experts, which is why it is important to ask them. In any case, the fact that those selling a product have asked themselves this question can already be an indicator.
Clinical trials on humans make the difference between a promising product and reliable one
Synergies and antagonismsA reliable product takes into account the biochemical synergies and antagonisms between substances. Some nutrients, in fact, get along together and can, for example, promote the absorption of each other. Other substances, on the other hand, do not get along well and taking them at the same time may cancel out their benefits. An example is that of vitamin B1 (or thiamine): allicin converts it into a form which is more easily absorbed, whereas some polyphenols (caffeic acid, chlorogenic acid and tannic acid) and flavonoids (quercetin and rutin) interfere with its absorption.