Ripped off from slashdot by me, written by 'Budenny'.

All bran is not the same. Wheat bran, contrary to the implication, is bad for you and has no dietary benefits. It irritates the intestines and blocks the absorption of nutrients. It is a myth that whole wheat bread has more vitamins and minerals and is therefore better for you than white bread. Yes, it has more vitamins and minerals. No it is not therefore better for you, because they are not accessible. What matters is not what is in it, what matters is what you can get out of it. The problem is phytates, which prevent absorption of minerals.

The right way to eat wheat bread is the way that was traditional until the rise of the steam baked industrial rapid rise loaf. That is, first, a slow fermenting rise, usually overnight. This makes the bread both lower glycemic index, and also more digestible. Second, flour which is not whole wheat but is relatively high extraction. This the so called grey flour of traditional French bread. Until modern times, when people talked about 'white' bread, what they meant was bread without the bran, a greyish color, but containing the germ.

The extraction rate varies from 75% or less for conventional white flour to 85% for brown but not wholewheat flour. In countries where bread is the staple, the extraction rate is usually in the low eighties and this is probably the sensible level. The rate in the US during WWII was raised to 80% - similarly in the UK, or perhaps a little higher. It would be a dramatic step forward for modern diets if it could be placed at that level today.

The same points apply to rice bran, which also should be avoided. It is striking that traditional cultures with long histories of healthy eating invariably mill rice and refine wheat, but never try remove oat bran. Both wheat and rice bran are better used by feeding to poultry, when the conversion into high quality protein is a much better use for it than irritating the human bowel to no nutritional effect.

Oat bran is in a completely different category. It does not irritate the bowel, and its nutrients are available. I believe the same to be true of spelt.

Its worth remarking that probably one of the main causes of obesity is the obsession with the low fat diet. Without any real evidence, we have embarked on a gigantic nutritional experiment in the Anglo Saxon countries over the last 30-40 years. We have gone from diets which were reasonably balanced in terms of saturated fats and complex carbohydrates, to ones which attempted to eliminate all saturated fats. However, the natural and normal craving for some fats has led to the substitution of polyunsaturated fats for saturated. There is no evidence that this is healthy, and much that it is far worse. In addition, since the available high carb foods are highly refined, we have then substituted for potatoes, rice and pasta, much sugar, including fructose. The result is a diet far worse than what we started with, and one which our evolutionary history has never prepared us for.

It is not an accident that this has happened at a time that the health food movement has metamorphosed into the supplements industry.

So what should we eat? Liberal amounts of meat, fish, eggs, butter and full-fat, non-homogenized milk. Absolutely no refined vegetable oils. Moderate amounts of mono-unsaturated vegetable oils (olive and peanut). No corn oil, safflower oil, hydrogenated vegetable oil, margarine. Liberal amounts of vegetables of all sorts. Liberal amounts of sourdough bread made with coarse white flour. Similarly pasta. White, not brown, rice. Parboiled is OK. Fruits in season. And fruit juice, if at all, in great moderation.