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Livescience_2014 03020.txt

#Are saturated Fats as Bad as We Have been led to Believe?(Op-Ed) This article was published originally at The Conversation. The publication contributed the article to Live Science's Expert Voices: Op-Ed & Insights. A US heart researcher looks set to inflame an argument over saturated fats. It has long been a health mantra that too much saturated fat like cheese and butter contributes to higher cholesterol and an increased risk of heart disease. But an editorial published in Open Heart suggests that saturated fats aren t as bad as we have been led to believe. Author James Dinicolantonio a cardiovascular research scientist at Saint luke s Mid America Heart Institute argues that the association between the high proportion of fat in total consumed calories and an increased risk of degenerative heart disease was based on selective data from the 1950s that overstated the risk. And the recommendations that it led to that we lower our intake of saturated fat and cholesterol and increase carbohydrate has given rise to the surging obesity. The association between fat calories and heart disease risk was made first by Ancel Keys in the 1950s who first suggested a correlation between between cholesterol levels and cardiovascular disease (CVD) which he later published in his Seven Countries Study. Dinicolantonio argues that another 16 countries were excluded from the data that would have made the association less clear and led to different dietary advice.##oeit was believed that since fat is the most#calorie-dense of the macro-nutrients a reduction in its consumption would lead to a reduction in calories and a subsequent decrease in the incidence of obesity as well as diabetes and the metabolic syndrome#he said. But turning to carbohydrates such as sugar and corn syrup has led to a parallel increase in diabetes and obesity in the US. Instead there s a strong argument that the increase in the consumption of refined carbohydrates was the causative dietary factor for diabetes and the obesity epidemic in the US#he said. The article concludes that while diets low in saturated fat can lower bad#LDL cholesterol switching to carbohydrates may increase another type of LDL cholesterol In a study that compared two low-calorie diets one low-fat and one low -carb the latter showed better results. Overall he argued no large observational studies have shown that low fat diets cut heart disease risk. Our view of fats has changed over time and rather than one homogeneous group they fit into a number of categories with some thought to be good and some bad. Unsaturated (less calorific compared to saturated fat) polyunsaturates (found in nuts seeds and fish) and monounsaturates (found in red meat olives avocados) have a good reputation when it comes to lowering cholesterol and heart disease risk while saturated fats (meat cheese) and artificial trans fats such as hydrogenated vegetable oil aren t so good. While trans fats are seen still very much as bad troubles over the established belief about saturated fats and heart disease risk surfaced in 2010 after the authors of a meta-analysis of 21 studies and nearly 350000 subjects concluded there was no significant evidence#that dietary saturated fat was associated with an increased risk of coronary heart disease or cardiovascular disease. Last October British cardiologist Aseem Malhotra published an article in the BMJ titled Saturated fat is not the major issue#.#In it he called for a re-evaluation of how we view saturated fat s role in heart disease. He said that though there was universal agreement over trans fats saturated fat was unnecessarily demonised.##oelow-fat diets have made paradoxically people more obese because people are consuming more things like sugar that are seen typically as low calorie#he said.##oeone of the problems is that there s misinformation among a lot of people#Now we re learning that it doesn t work: rocketing obesity and type 2 diabetes. We need people to go back to eating normal food which includes eating saturated fats like cheese.##He said normal#meant avoiding things marketed as low fat and low in cholesterol and said the Mediterranean diet would be the ideal; rich in olive oil nuts fruit and vegetables and low in refined carbohydrates. Saturated fat was part of a healthy diet he said but not from fast food. If you have a diet that has saturated fat in it and non-processed foods then effect is nominal and maybe even slightly beneficial.##He added: The message going out has to be the right message clearly the reality is that it hasn worked t.##While Brian Ratcliffe professor of nutrition at Robert Gordon University in Scotland praised Dinicolantonio for a welcome addition to the debate#that challenged dietary dogma#other experts warned that the article was only likely to lead to confusion. David Sullivan clinical associate professor at Sydney University said: This article and others like it slip between nonidentical terms to suit their argument. It switches between total and saturated fat as well as total and LDL cholesterol. Likewise it picks and chooses endpoints to suit so-called#surrogates like blood test results weight CVD cancer and total mortality.##Sullivan said that there were some studies that did deviate from what was expected but that this was understandable in the complex field of nutrition.##He said the 2010 meta-analysis (supported by the National Dairy Council) also found that evidence from studies was consistent in finding that the risk of coronary heart disease was reduced when saturated fat was replaced with polyunsaturated fat. In other words saturated fat many not increase your risk (as the study found) but substituting with a better fat could lower it. Sullivan said a Mediterranean style diet recommended by Dinicolantonio was most definitely a low saturated fat diet.##Tom Sanders head of diabetes and nutritional sciences in King s college London s School of medicine said: This article rubbishes the relationship with saturated fat and CVD misrepresents the scientific evidence and then goes on to put the blame on sugar.##oeit is beyond reasonable doubt that elevated LDL cholesterol is a major determinant of risk factor for cardiovascular disease. The saturated fatty acids palmitic myristic and lauric acids raise LDL cholesterol in increasing order in meta-analysis human experimental studies. Sugar intake does not affect LDL-cholesterol or blood pressure.##So what are we to believe? The Mediterranean diet (ironically developed by Keys) healthy (but not low-fat) rich in omega-3 fatty acids lots of fruit and vegetables and less red meat appears to go some way in bridging the gap. Tony Blakely a professor at the University of Otago in Wellington New zealand has suggested more agreement than might at first appear. There is a reasonably solid core of agreement if one looks closely#he said. These included the emerging consensus that overeating of refined carbohydrates is bad for you #and agreement on the benefits of eating more fruit and vegetables especially to substitute other aspects of the diet.##This article was published originally on The Conversation. Read the original article. The views expressed are those of the author and do not necessarily reflect the views of the publisher. This version of the article was published originally on Live Science. b

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