Study: EU vitamin level-setting methods ‘fatally flawed’

Models being utilised by European authorities to determine upper safe limits (USLs) for vitamin and minerals used in food supplements are flawed and should be subject to “proper scientific validation”, say the authors of a study published in Toxicology.

Lead author, Robert Verkerk PhD, the scientific and executive director of Alliance for Natural Health (ANH) International, and a vocal critic of EU food law, called on the EU to halt its USL deliberations until new methods could be developed that better reflected the available science.

The study points out that the methodology being used by the EU regulators is designed for toxic chemicals and likely to set USLs at low levels where health benefits will be denied and 1000s of products stripped from shelves in many member states.

"As clarified by the FAO/WHO expert group (2006), a uni-lateral formulaic approach to risk management, such as that taken by the German BfR [Federal Institute for Risk Assessment], is inappropriate," Verkerk and co-author, Stephen Hickey state.

There is a need to incorporate additional allowance for biological variation and differing molecular forms for nutrients. In addition, the present critique exposes considerable weaknesses associated with an alternative model developed by the trade associations EHPM and ERNA."

Methodology issues

The authors state that the risk-analysis methods winning favour among EU risk assessors have several “fatal flaws”:

  • Fails to take into account the fact there can be both over and under exposure to nutrients
  • The presence of multiple adverse effects in the case of many nutrients at different intake levels

  • Overlap between risk and benefits for particular nutrients in given sub-populations (e.g. preformed vitamin A)
  • Differences in risk caused by different molecular forms of nutrients within the same nutrient group (e.g. iron sulphate and ferrous bisglycinate, nicotinic acid and inositol hexanicotinate)
  • Incomplete data (especially intake-response data) to allow accurate risk characterisation
  • The assumption (made by both the BfR and EHPM/ERNA) that risk to public health is inversely proportional to the margin between the referencing labelling value and the USL. “In some cases, this may lead to mis-characterisation of risk, including both its probable under-estimation (e.g., particular chromium and vitamin K molecular forms) or over-estimation (e.g. vitamin C, natural carotenoids).”
  • Unworkability of harmonisation across a bloc of countries with vastly different dietary habits and population profiles
  • Difficulties in accounting for the nature, severity and reversibility of adverse health effects.

Alternative measures

The researchers forward suggest a range of measures that should be considered:

  • More complete characterization of risk, using empirical data for validation, leading to the less arbitrary use of uncertainty factors
  • Provision of USLs for multiple sub-populations where relevant
  • Provision of USLs and, where relevant, maximum permitted levels, for members of the same nutrient group (as is the case for nicotinic acid and niacinamide) where there are clear differences in bioavailability and/or toxicity.

  • Where there is an overlap between risk and benefit, a common currency should be developed, such as quality-adjusted life years (QALYs) or disability-adjusted life years (DALYs), as proposed by the European Food Safety Authority in 2007
  • More thorough risk consideration for subpopulations when the USL is exceeded.

Source: Toxicology

doi:10.1016/j.tox.2009.12.017

'A critique of prevailing approaches to nutrient risk analysis pertaining to food supplements with specific reference to the European Union'

Authors: Verkerk, R.H.J., Hickey, S., A