Folic acid decision was based on best science
9 September 2013
The Prime Minister’s Chief Science Adviser has released an excellent report on the importance of government decision-making being underpinned by good scientific evidence. This is something that the Food & Grocery Council supports absolutely, particularly with regard to the regulation of food.
However, the report lists the Government’s decision not to mandate folic acid in bread as an example of decision-making which was not underpinned by science, and it’s on this one aspect where FGC must disagree.
The Ministry for Primary Industries team which oversaw this decision is one of the most knowledgeable policy teams in the public service. They looked at all the science, commissioned additional research locally, and worked with industry to develop a voluntary and significant fortification scheme, and it’s for this reason we believe that the report does a disservice to those involved by suggesting it was an example of a policy decision made “without the benefit of transparent peer-reviewed scientific advice”.
The decision was made by then-Food Safety Minister Kate Wilkinson in August last year after submissions by FGC, including others, to the Biosecurity, Food and Animal Welfare Directorate of the Ministry for Primary Industries.
Here’s what Sir Peter Gluckman’s report, entitled ‘The role of evidence in policy formation and implementation’, says:
“There are public debates which have influenced policy decisions in recent years where the New Zealand public would have been better served had an evidence-based process been used within the policy formation process and within the public dialogue that informs it. We have had examples where public consultation has occurred without the benefit of transparent peer-reviewed scientific advice. This has limited the quality of the public and media discourse and may have well led to decisions that in other circumstances might have been very different.
“One example is that of folic acid supplementation of bread. A decade ago there may have been no scientific consensus in this area, but there is now a strong consensus that it is safe and effective in reducing the incidence of neural tube defects in newborns. Documents from the Ministry of Primary Industries made that clear, yet consultation went ahead in the absence of these reports being widely available. There may well be valid values-based reasons why a country may decide not to supplement bread with folic acid, for example perceptions of medicalising a common food staple (although we have long supplemented salt, and more recently bread, with iodine), or because a cost-benefit analysis may not seem to justify it. But irrespective, in this case decisions were made with a component of public consultation in the absence of up-to-date scientific data being made freely available.”
FGC and the baking industry (and the general public, for that matter) did not support mandatory fortification of folic acid for science-based reasons. Our submission backed up a lot of other advice that was in the public arena, and we made sure the information we had was freely available. Our position was based on an independent report that FGC and the NZ Baking Industry Trust commissioned in 2011. Its purpose was to review scientific and clinical research on the public health and safety aspects of the addition of folic acid to food and/or consumption by humans which had been published between 2008 and 2011, with particular reference to New Zealand. It was conducted by Professor A. David Smith, of the Department of Pharmacology at Oxford University, and Professor Helga Refsum, of the Department of Nutrition, University of Oslo. Professor Smith had formerly been the Head of Department, and together they have a combined total of 50 years’ experience in the research of folate, and have published some 130 publications in these fields.
In particular, they looked at:
- The size of the problem of neural tube defects.
- The impact of folic acid fortification on the prevalence of neural tube defects.
- Any additional possible benefits of fortification.
- Possible harmful effects of fortification.
- The relationship between folate and cancer.
- The likely overall balance in public health benefit or harm if fortification were to be introduced.
That report, and further advice, found:
- Folate levels in New Zealand women are as good if not better than those of women in the United States after mandatory fortification was introduced there.
- The folate status in the United States appears to be sufficient to prevent all folate-sensitive neural tube defects.
- Fortification may prevent, conservatively, up to six neural tube defect pregnancies each year in New Zealand, but the report suggests that given the significant reduction of folate-sensitive neural tube defects over the past two decades, the current rate is probably at a ‘floor level’.
- There is a potential for harm to small subsets of the population from consuming too much folic acid, including risks in the consumption of folic acid by non-target groups such as the elderly (impacting on vitamin B12)9, and interactions with anti-folate drugs making them potentially less effective.
- The more complex relationship is between folic acid fortification and cancer. Profs Smith and Refsum reported that a “meta-analysis on 10 trials (38,000 people) … show an overall 7% increased risk of new cancers, with a 24% increased risk in prostate cancer.”
If that is not using “transparent scientific advice” to inform, then we’re not sure what is.
As we said at the time, rejecting mandatory fortification was the right thing to do, based on the available science, which remains increasingly unclear. Those who argued there was a scientific consensus supporting mandatory fortification overlooked that, as new science is published, sometimes there are academic thought-leaders such as Profs Smith and Refsum at the forefront of their topic who start to challenge the status quo. Though both are supportive of folic acid in the diet, they simply pointed out that too much of it can lead to negative outcomes, and that folate levels for New Zealand women were very good without state intervention. And as long as that was the case, it didn’t make sense to mandate fortification and effectively expose the whole population by artificially raising levels of folic acid in an attempt to reach a small number of women.
From an FGC perspective, our position was based on the best scientific advice from experts in the field.
In terms of the final decision to support a voluntary approach, we have no evidence as to what part our submission played in this. We can only assume it was considered carefully, containing as it did evidence from two world authorities on the subject.
See the report ‘An update on folic acid fortification: benefits and risks 2012’ by A David Smith and Helga Refsum here.