According to GP Tom Smith in The Guardian on Saturday 19th January 2013, he would NEVER follow a low carb diet because it may KILL YOU!
His conclusion is based on the results of a study conducted on women in Sweden who were monitored for an average of 15 years. The report was published in the British Medical Journal on 26 June 2012 (http://www.bmj.com/content/344/bmj.e4026)
Dr Smith states that;
“Those who stuck to the low carbs and high protein had a rising risk of dying from heart attacks and strokes, depending on how strict they were and for how long they endured them. There was a staggering 62% higher risk among the women eating the strictest diet over those who ate normally.”
If Dr Smith had bothered to keep himself informed of the latest developments in human nutrition (see for example the publications of Gary Taubes, Barry Groves, Malcolm Kendrick and Uffe Ravnskov) he would have realised that these conclusions just do not ring true The reality is that this work was an appalling piece of research which the editors of the BMJ should never have agreed to publish. It was subject to devastating criticisms in the immediate aftermath of the publication( and it seems that Dr Smith is unaware of these or has chosen to ignore them. (http://www.bmj.com/content/344/bmj.e4026?page=1&tab=responses)
Here is a selection of the comments:
- The actual incident rate was 0.19% which is just under 2 per 1000. Those who were designated as low-carb had an incident rate of 0.23% while those who were considered not to be low-carb had an incident rate of 0.14%. So Dr Smith’s staggering 62% is a relative value based on a comparison of two extremely small numbers!
- The researchers used only one single baseline dietary data set upon which to base their 15 years long study and its conclusions. This consisted of a food frequency questionnaire in which subjects were asked to identify how frequently they consumed 80 different food and beverage items over the course of the past 6 months. It is obvious that the dietary recall data is inaccurate as the authors report an average daily calorie consumption of only 1,561 calories which is simply not credible in view of FAO data showing that the Swedish per capita average calorie consumption at the time of the survey was 2,990 calories. The author of this concluded
“Given the paper’s scientifically horrifying flaws and the editorial’s completely clueless conclusion they’re useless contributions to the medical literature. In fact I’d describe them as worse than useless in that they’re unforgivably, irresponsibly and shamefully misinformative – something our already incredibly nutritionally confused world really didn’t need.”
- Another respondent commented:
“I’m very sad, because I don´t understand why the BMJ, one of the best medical journals in the world, has published an article so biased.” He went on to suggest that the conclusion to the article should have been:
“This medical paper has both a very low quality and a lot of major biases, therefore it shouldn´t be published because its flaws not only have a confounding effect in nutrition science but can generate emotional shock in people under these kind of diets”
- Even if the results had any validity, they would only demonstrate an association which does not prove cause and effect
- Here is a further comment:
“Like many before them, they conduct sophisticated secondary analyses of bad primary data. This is a statistical smokescreen that conceals the fundamental problem.”
- And a final one:
“This study is a total disaster. Low protein is 1, high protein is 10, low carbohydrates are 10, high carbohydrates is 1. So to have sum score of 11 it can be low protein (1) and low carbs (10) or high protein (10) and low carbs (1) or any sum between 1+10, 2+9, 3+8, 4+7, 5+6, 6+5,7+4, 8+3, 9+2 or 10+1, all give 11 as score. So to have a Low Carb, High Fat (LCHF) dinner with a steak and bearnaise sauce with some asparagus (normal protein, low carbohydrate, high fat) or a hamburger with bun, fries and sweet beverage, (normal protein, high carbohydrate, medium fat) there will be no difference in score!
So this study is just like rolling dice and trying to make statistics out of it. It is definitively not science.”
I am afraid Dr Smith has been totally irresponsible. It appears that as with so many public health professionals it is an article of faith that carbohydrates are an essential requirement for the human body. In fact nothing could be further from the truth. Pure carbohydrates such as sugar only provide energy, which of course is also available from fats and proteins. Humans can exist perfectly well without carbohydrates and there are many examples of populations which do just that.
What is particularly regrettable is that the recommendation to reduce saturated fat has absolutely no validity. The official target to reduce saturated fat by 25% which was set almost 30 years ago has actually been achieved. Over the same period we have seen the incidence of obesity take off and diabetes has approximately quadrupled. This is largely due to the increased consumption of carbohydrates plus possibly a deficiency of key fats.
It is now virtually certain that our current public health problems are a direct consequence of the implementation of the official dietary recommendations. It is an absolute scandal that the medical profession is still recommending that those with diabetes are being strongly advised to reduce fat and increase their intake of complex carbohydrates. The internet is packed with personal case histories from individuals who have abandoned this advice with the result that they have been able to improve their health by consuming a diet which is low in carbohydrates and high in fat. Almost all have been able to reduce their medication and some have been able to do without completely. In addition they almost invariably lose weight, reduce triglycerides and increase HDL cholesterol.