I began this blog with discussion of what
is wrong with the Banting argument; while there is more to come on that subject
I would like to turn my attention to what is right with it.
One thing I think anyone interested in nutrition
can agree on is that there is a problem. Certainly in South Africa there is
overwhelming evidence of very high levels of obesity which directly correlate
with poor health outcomes. In a recent high quality article it was found that
in 2013 the rate of obesity in South African women was 42%. This compares to a
rate of 34% in USA and although South African men do better it's a shocking statistic. The map below summarises adult female obesity across the
world with South Africa being one of a handful of countries in the red zone.
I have heard Professor Noakes on a number of occasions say that people in South Africa are obese because they don't eat a LCHF diet. He is somehow implying that if you disagree with the LCHF argument you must also think there isn't a problem. This couldn't be further from the truth. Whatever anyone thinks about dietary strategies, no one in their right mind is denying that there's a problem.
The Banting argument has at least 3 tracks which all followers seem to agree on. First it is that LCHF diets are the equivalent of 'the elixir of youth', secondly that sugar is very bad for you and thirdly that statins are pretty much the work of the devil. Whilst points 1 and 3 will be the subject of future posts there is a great deal of evidence showing the harms of sugar. If you only read one academic paper about sugar its worth reading Sanjay Basu's
The Relationship of Sugar to Population-Level Diabetes Prevalence: An Econometric
Analysis of Repeated Cross- Sectional Data. The data in this paper are purely observational and therefore sit very low in the EBM pyramid. However, this group make a convincing argument for the role of sugar consumption in diabetes. There is unlikely every to be a randomised controlled trial of a high sugar diet and so this is the highest level of evidence we are ever likely to get on this precise question.
Karen Thomson is part of the LCHF community and is very vocal on the dangers of sugar. Her website and books are titled 'The Sugar Free Revolution'. Whatever the truth of the message one thing Karen Thompson is not delivering is a revolution. In fact her story is rather old hat. If you only read one book on the subject I recommend 'Pure White and Deadly' by John Yudkin. Yudkin was a pioneering endocrinologist who cottoned on to the dangers of sugar way back in the early 1970's and wasn't afraid to tell the world. The problem was that the world wasn't ready to listen. Gradually however the world has woken up to the dangers of over consumption of sugar. There is no reason to think you should be completely sugar free any more than you should be completely alcohol free but consumption in moderate to high quantities seems to be dangerous.
So, its easy to agree with the LCHF brigade on a number of issues. Firstly that there is a big problem with diets in South Africa and secondly that sugar in large amounts is probably dangerous. Neither of these is revolutionary or novel but that doesn't stop people writing books and making money out of them.
References
Ng et al Global, regional, and national prevalence of overweight and obesity in children and adults during 1980–2013: a systematic analysis for the Global Burden of Disease Study 2013. Lancet Volume 384, No. 9945, p766–781, 30 August 2014 http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(14)60460-8/fulltext
Basu S, Yoffe P, Hills N, Lustig RH (2013) The Relationship of Sugar to Population-Level Diabetes Prevalence: An Econometric Analysis of Repeated Cross- Sectional Data. PLoS ONE 8(2): e57873. doi:10.1371/journal.pone.0057873
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