I don’t believe bread, as we commonly eat it, is a healthy or wholesome food (far from it). And last year I was surprised to read a ‘review’ lauding the nutritious attributes of bread and lamenting the fact that, here in the UK, bread consumption is declining. The review was authored by a scientist connected with the British Nutrition Foundation, but was funded by the bread manufacturer Warburtons. You can read my original post here.
The head of the British Nutrition Foundation emailed me with some sort of defence of the article. I wrote about the response and gave my own reaction to it here.
If you’ve been bothered to click on those links and read both the blog posts you may be forgiven for getting the impression I am no fan of the British Nutrition Foundation. The BNF is a charity, and describes itself thus:
The British Nutrition Foundation (BNF) was established over 45 years ago and exists to deliver authoritative, evidence-based information on food and nutrition in the context of health and lifestyle. Accurate interpretation of nutrition science is at the heart of all we do.
This reminds me of the sort of rhetoric we doctors spout about being ‘evidence-based’ when much of medical practice is anything but (we just say it is). And in the case of the BNF, there’s no denying the fact that it takes funding from a wide range of factions within the food industry, and therefore its position is clearly compromised. This conflict of interest possibly helps explain how the BNF comes to publish an utterly one-sided account of the nutritional qualities of bread, with barely a mention of the very real risks associated with eating this food.
During an internet search today I was directed to the BNF website today, and specifically its take on recent research which found that in a study dating back some 40 years, swapping saturated fat for foods rich in supposedly healthy omega-6 (polyunsaturated fats) caused men to be more likely to die, including from heart disease. The authors of the study put it in the context of other similar studies that found no evidence of harm, but no evidence of the much-touted benefits either. At best, the evidence suggests no benefits and possibly some risk. You can read my account of this evidence here.
So, how did the BNF interpret the evidence? Look here to find out. After reporting the findings of the research quite well (I think), the BNF tells us this:
Cholesterol is a well-known risk factor for cardiovascular disease and the intervention group did show a decrease in blood cholesterol which is consistent with previous studies. In addition, more recent prospective cohort studies have shown a reduction in cardiovascular disease risk with a higher n-6 PUFA or n-6 and n-3 PUFA diet.
I see two main problems with this:
1. Why is the BNF telling us about the impact of the intervention on cholesterol? Are they perhaps hoping that by mentioning it we will forget that the research actually showed that the risk of heart disease and death went up (as cholesterol went down)?
2. They refer to ‘prospective cohort studies’. These are what are termed ‘epidemiological studies’ that look at associations between things. However, these studies don’t really tell us much, and in particular they are not useful for discerning what the impact of changing fat intake is on health.
To know that, we need ‘intervention’ studies, just like the ones that showed no benefit from swapping saturated fat with omega-6-laden foods, and some evidence that this strategy may be quite hazardous to health.
The BNF also tell us this:
It is also worth noting that the study was conducted in men who had a high risk of mortality, so although the findings warrant consideration, the results may not be applicable to the general population in the UK today.
But the bods at the BNF should know that, generally speaking, the greatest likelihood of benefits are seen in the people at highest risk. The likelihood is that the results would have been even worse in the standard British population. Then we get this:
The study participants were aware of which group they were in, intervention or control group, and as such it is possible that participants in the control group made more of an effort to make lifestyle changes such as increasing physical activity.
Yes, but it’s the same for those in the intervention group too. In both situations, all we can do is speculate. Which is all we can do when we consider their final point here:
Dietary intake of other nutrients and food groups, such as trans fatty acids and fruit and vegetable intake, were unfortunately not reported.
And finally, their summary:
In summary, although this is an interesting study, more clinical evidence is needed before any generalisation of the findings are made. The advice for consumers should still be to choose foods with a lower saturated fat content and to choose fats and oils that supply primarily unsaturated fats.
This, even though the totality of the evidence does not support this intervention as being healthy.
Notice the title of the BNF statement: ‘Confusion on fats and heart health.’ Quite. It occurs to me that all the BNF have done here is perhaps add to the confusion by giving us its unique take on the scientific evidence. But then again, if you had Unilever as a ‘sustaining member’ of your organisation, what would you do?