Fat in diet is an emotive and confusing issue. In the USA, the American Heart Association is still adamant that generous amounts of omega 6 polyunsaturates are essential to heart health, despite the fact that these essential fats were never abundant in the human diet until the last century. At the AICR (American Institute for Cancer Research) they are warning that too much of the stuff increases the risk for some cancers. Look at the National Institutes for Health website, and they are talking about inflammation from excess omega 6 being a risk factor for coronary heart disease. In the UK, the government's message is still that omega 6 polyunsaturates are the heart-healthy choice. Many authorities and individuals are extolling the virtues of omega 3 for good health, but hardly anyone is talking about the balance between these two classes of polyunsaturate, and the health implications of the very radical, very recent change in this balance in the average 'western' diet.
Well, that didn't do anything to relieve the confusion, did it? Luckily, there are people around who are giving us the bigger picture, so we can make up our minds on this issue. There's a lot of science here, and it can get quite deep and narrow, so it often falls to the generalists like science writers to gather up all the threads, go back to the scientists and talk to them, and make it coherent for the layperson to read. One such writer is Susan Allport, who looked at a millenia of human diet, at the sudden dramatic changes in recent years, and dug up the science behind these polyunsaturated fatty acids. In her search for the facts, she contacted many scientists, a number of whom have had very little exposure for their findings in a time when the scientific and medical orthodoxy is in favour of diets radically different from those that mankind has eaten for thousands of years. Swimming against the tide that seeks 'superfoods' and 'magic bullets' rather than looking for variety and balance, these scientists have between them uncovered the secrets of nature's 'fast fats' and 'slow fats'.