Maria Z. Tsimidou Dimitrios Boskou In the context of Regulation (EC) No1924/2006 1 a health claim is any statement about a relationship between food and health based on an opinion of the European Food Safety Authority (EFSA), which is responsible for evaluating scientific evidence provided by the interested parties. The aim of the Regulations is to "enhance the consumers' ability to make informed and meaningful choices" providing them with messages that are "clear, accurate and based on evidence accepted by the whole scientific community" through claims that appear on "labeling, presentation or marketing in the EU". Since its implementation many different points of view have been expressed on various issues in scientific fora, official meetings and various publications. Clear terminology of the authorized claims and adoption of appropriate protocols to verify them are important for the effective realization of the aims of this regulation and merit the attention of independent scientists and regulatory bodies. There were thousands of submitted applications but only a few claims have been authorized so far. Looking through the extended list of 2,282 uploaded claims in the respective register 2, it is evident that it contains "traditional knowledge", passed down from generation to generation (honey, olive oil, walnuts, fruits, vegetables) as well as sophisticated claims, unknown to non-specialists (gamma-linoleic acid, olive "polyphenols", plant sterols and stanols, etc). Regarding olive oil, 16 petitions belonging to the category Article 13.1 (a) "general function" claims of the regulation were submitted. Seven of them were for olive oil/olive pomace oil as a food (multiple entries 1332, 1316, 1244), one for squalene (entry 1708) and the rest of them (multiple entries 1882, 1367, 1878, 1332, 1639, 1793, 1877, 1333, 1638, 1696, 2885) were for olive phenolic compounds differing in wording, source and health effects. The only authorized health claim, listed in the Regulation 432/2012 3, relates the level of olive phenolic compounds and the impact on the protection of blood lipids from oxidative stress. The claim "olive oil polyphenols" can be used only for a natural olive oil that contains at least"5 mg of hydroxytyrosol and its derivatives (e.g., oleuropein complex and tyrosol) per 20 g of olive oil". The disclaimer "a daily intake of 20 g of such an olive oil provides the expected beneficial effects" should be also given on the label considering current concerns on consumption of high energy foods such as fats. In the present editorial, we shall focus on this claim as a characteristic example of the problems that may appear upon implementation of the regulation due to lack of clarity in terminology and mainly due to the absence of a suitable analytical protocol for the determination of the bioactive compounds behind the claim. Olive oil is the oil produced from the flesh of olives. Since antiquity its production is accomplished through physical processes that are currently fully controlled to avoid oxidative deterioration and loss of the endogenous bioactive ingredients. The result of these processes is a fruit juice named "virgin olive oil" and not "olive oil". The highest commercial quality in EU and worldwide is named "extra virgin olive oil" and this is the only one that can contain the above mentioned amounts of the polar phenolic compounds if the olives have been processed at the right maturity stage under appropriate conditions 4. The use of the term "olive oil" does not help the average consumer to make an "informed" and "meaningful" choice because it is not clear which of the commercial products available on the shelf contain the authorized ingredients. Not all of "olive oils", not even all of the "extra virgin olive oils" are expected to contain high concentrations of the desirable ingredients to which the claim refers. Nevertheless, "virgin olive oil" is the correct term to refer to an oil which has not been subjected to any refining process. The bioactive phenolic compounds of virgin oil oil, which have been a hot topic of research the last 30 years, are mainly the simple phenols hydroxytyrosol, and tyrosol in their free form or linked to aldehydic forms of decarboxylmethyl elenolic acid (glycosylated or not), some phenolic acids and lignans 5. None of these compounds bears at least two phenolic rings in the molecule and therefore cannot be referred to as "polyphenols". The term "olive oil polyphenols" is a wrong term that will confuse consumers in the near future if "polyphenols" from tea, for example, will be authorized a health claim. It is better to characterize them as "virgin olive oil bioactive phenols" or as "virgin olive oil polar phenols" to emphasize the difference from another class of phenols, tocopherols, the non- polar phenols. The claim was authorized for "the impact on the protection of blood lipids from oxidative stress" of the named compounds. This health impact is due to the cumulative effect of all the phenolic compounds transferred from the olive drupe to the oil matrix during processing and not to a particular one even though experiments have been carried out for the activity of individual compounds, too. Levels of individual phenolic compounds differ from virgin olive oil to virgin olive oil but generally the secoiridoids dialdehydic forms of elenolic acid linked to hydroxytyrosol (3,4-DHPEA-EDA) and tyrosol (p -HPEA-EDA), oleuropein and ligstroside aglycons, are the main phenols followed by lignans, tyrosol and hydroxytyrosol, whereas the concentrations of phenolic acids is low. The concentration of tyrosol and hydroxytyrosol is usually low in fresh oils but increases during oil storage due to the hydrolysis of secoiridoids, which contain these phenols in their molecular structure. Oleuropein (a glucoside) is present in ppm or sub-ppm quantities in olive oil. Thus, the expression "5 mg of hydroxytyrosol and its derivatives (e.g., oleuropein complex and tyrosol) per 20 g of olive oil" is unclear and creates additional confusion as it does not describe clearly which the main constituents of the biophenols fraction are. For example, a more appropriate expression could be "hydroxytyrosol/tyrosol and their bound forms" Soon after the release of the Regulation 432/2012 various scientists questioned unclear points concerning terminology and analytical methods for the accurate determination of the compounds covered under the claim. The International Olive Council (IOC) responded through an open call for proposals on improvement of the existing HPLC procedure or even adoption of a new one. The development of a validated analytical procedure for official use is important for the producers and other interested parties, who for the moment cannot benefit from this optional claim due to uncertainties in the implementation of the regulation. Scientists have antithetical points of view regarding the characteristics of the analytical method that should be recommended for adoption. Should it be one at the edge of analytical state of the art today? If yes, how many laboratories will be entitled to carry such an analysis out? Should it be a protocol that will address the core of the health claim in a cost effective, meaningful and repeatable way even if not the most accurate? Why not. Most official methods have such features. Indeed, experienced scientists from different laboratories from Spain, Greece and Italy proposed simple analytical procedures for the measurement of total hydroxytyrosol and tyrosol content by HPLC or GC after appropriate sample preparation 6-8. Despite the differences in protocols, the basic principle is the same; the method should be simple, repeatable, easily to adapt to the conditions of as many analytical laboratories as possible. This approach is quite different from that supported by laboratories applying high throughput analytical techniques 9. The latter propose more accurate protocols to identify and quantify every molecule of the bioactive phenolic compounds present in any form, simple or bound. Olive oil, however, is a food, not a drug, and not a food supplement, for which the exact dose of the active ingredient should be subscribed by a medical doctor. Foods bearing health claims belong to a subcategory of products for frequent or daily use that offer benefits beyond those of the known nutrients. In particular, a claim under the meaning of Art. 13.1 (a) should be based on generally accepted scientific evidence and covers the role of a substance in the growth, development and functions of the body. Obviously, such a claim is not a dose-activity relationship message to consumers. According to the regulation 432/2012, the virgin olive oil that can bear the claim on its label should contain the particular amount of 5mg of the bioactive compounds per 20 g. An official method for the total content and individual phenols, which would be practical and would guarantee the comparison of quantitative approaches from different laboratories does not exist 10. The widely known colorimetric method using the Folin–Cioacalteu reagent is not suitable as other phenolic compounds or any other oxidizable organic compound may react and be co-determined. Most of the HPLC procedures do not lead to baseline separation of all possible compounds in the polar fraction, which cannot be safely identified unless mass detection is available. Quantification so far was based on certain compromises as some necessary standards were expensive and unstable. Similar observations could be made for GC procedures. NMR procedures seem extremely sophisticated for quality control purposes. Hydrolysis of bound forms and then quantification of total hydroxytyrosol and tyrosol content prior to HPLC or GC analysis could be a reasonable compromise that deserves attention for its simplicity and relevance to the bioactive phenolic moieties covered by the claim. Moreover, such a procedure can easily undergo a ring test involving a great number of laboratories as the facilities required are essentially a liquid or gas chromatograph equipped with a diode array or an FID and two standards. Still, the part of the analysis that needs consensus among scientists is the hydrolysis part. If such a procedure is soon available, then analysis of a great number of samples will be necessary to ensure that the required minimum amount of bioactive phenols in the health claim is realistic or not. It cannot be precluded that the minimum amount of 5mg /20 g oil would not be then revised. Authorization of the health claim aroused enthusiasm and was considered by the SMEs in the producing countries as a means to convey more benefits from virgin olive oil consumption to consumers and also to gain better prices for their products. Such an interest had not been expressed by producers, industry and mass media so far for important health claims regarding virgin olive oil that are easily grasped by the consumers. For example, it is far clearer to them that (a) olive oil is a good source of alpha-tocopherol, the most bioavailable tocopherol form that is found at an optimum ratio of unsaturated fatty acids/tocopherol content; (b) it contains the highest content of monounsaturated fatty acids among all natural plant oils 11. A health claim, and especially a proprietary health claim, seems to be more attractive than a nutrition claim in marketing and may partially justify why industry urges to speed up authorization process. However, technical gaps may cause considerable delays, from authorization to the implementation of a particular claim and can practically jeopardize benefits anticipated by the applicants. The authors declare no conflict of interest. Maria Z.
No takes yet. Share an insight, caveat, or question.
Tsimidou et al. (2015) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: