There's very little evidence that it does. You just have to look at the recent article on salt (http://news.ycombinator.com/item?id=4069613 http://news.ycombina

There's very little evidence that it does. You just have to look at the recent article on salt (http://news.ycombinator.com/item?id=4069613 http://news.ycombinator.com/item?id=4069613) to see that conventional wisdom is often flawed. Similar cases were made for eating cholesterol (it has no effect on blood cholesterol) and fibre (doesn't prevent bowel cancer). There is strong evidence that eating a "western diet", high in calories and processed food, will cause obesity, cancer, diabetes, etc. but there's a lot of disagreement as to what that root cause is.