Diet conscience Americans have been swapping butter for margarine for decades in the hopes that it would help them lose weight and avoid heart disease. The low fat craze really began after in the mid-1970s after Sen. George McGovern held committee hearings on the health of Americans, which culminated in a report called the "Dietary Goals for the United States."  This report advised Americans to eat a diet low in saturated fat. Now decades later, Americans are bigger and it looks like McGovern's recommendations were wrong all along. The Telegraph reports:

Scientists have discovered that saturated fat does not cause heart disease while so-called ‘healthy’ polyunsaturated fats do not prevent cardiovascular problems.

In contrast with decades old nutritional advice, researchers at Cambridge University have found that giving up fatty meat, cream or butter is unlikely to improve health.

They are calling for guidelines to be changed to reflect a growing body of evidence suggesting there is no overall association between saturated fat consumption and heart disease.

The team, whose results appear in the journal Annals of Internal Medicine, conducted a "meta-analysis" of data from 72 studies involving more than 600,000 participants from 18 countries.

A key finding was that total saturated fat, whether measured in the diet or the bloodstream, showed no association with heart disease.

In addition, levels of "healthy" polyunsaturated fats such as omega 3 and omega 6 had no general effect on heart disease risk.

Only omega-3 fatty acid found in oily fish was linked to a lower risk of heart disease. However, popular omega-3 and omega-6 supplements appeared to have no benefit.

So, what should Americans take away from this latest research? Well, first, they might consider integrating butter back into their diets (in moderation, of course).  But most of all, they should understand that the human body is complicated and researchers make mistakes and often offer poor guidance. People should also understand that the government creates guidlines based on the newest information. No one — not even Washington bureaucrats — can see into the future, and no one knows what will be discovered a decade from now. I'm not a nutritionist, nor am I a model of perfect physical health, but I tend to think health advice follows Occam’s razor, which says the simplest answer is often the correct answer. Applied to eating right, the best advice always seems to be that people should practice a little common sense — limit portion sizes and get some moderate exercise. Fad diets and fad-following government recommendations can't beat that.

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