Responding to last week’s publication of 31 health claim opinions relating to 416 submissions, NutraVeris said the rejection of green and black tea antioxidant claims among other demonstrated an uneven playing field in evidence requirements.
“Compared to previous assessments that lead to positive opinions on similar generic health claims (‘protection of DNA, proteins and lipids from oxidative damage’), a first reaction can be that huge discrepancies appear between the level of scientific evidence which was expected for this plant compared to that which was considered sufficient for vitamin C and selenium,” said Thomas Pauquai, the head of health claims and food safety at NutraVeris.
“However, what has probably made the difference is the recognition of ‘generally accepted’ rules that these micronutrients play against oxidative damage in the body, as confirmed by consensus opinions/reports from authoritative bodies and reviews.”
Pauquai questioned why EFSA’s Panel on Dietetic Products, Nutrition and Allergies (NDA) had altered consideration of the proposed claim for green tea from, “protection of DNA, proteins and lipids from oxidative damage is beneficial to human health” to “protection of DNA, proteins and lipids from oxidative damage may be a beneficial physiological effect”.
The NDA’s rejection of risk factors (otherwise known as biomarkers or endpoints) had played their part in the negative opinions, but provided valuable learning, Pauquai said.
The NDA stated that:
- “the total antioxidant activity/potential of plasma are not considered to be markers of oxidative damage”
- “the formation of malondialdehyde using a colorimetric assay as well as the resistance of LDL to oxidation are not suitable markers to assess lipid peroxidation”
- “the variant of the comet assay does not specifically measure DNA oxidative damage but general DNA damage independent of its origin”
- “the evidence provided does not establish that urinary 8-OHdG reflects oxidised DNA within cells”
Only plasma phosphatidylcholine hydroperoxides (PCOOH) measured by high-performance liquid chromatography-chemiluminescence (HPLC-CL) was recognised as an acceptable biomarker by the NDA, but it said one study in the submission that used the measure failed to demonstrate significant effects of green tea catechins on lipid peroxidation.
The opinion can be found here.
The full text of the 2006 nutrition and health claims regulation can be found here.
The science, testing and regulation surrounding antioxidants will be discussed at the upcoming NutraIngredients Antioxidants 2010 Conference. For more information and to register, please click here .