23 May 2017 - One of the reasons why sourdough breads last longer than a normal bread is that a sourdough culture will automatically produce a bacterial strain called Lactobacillus hammesi that will produce a "potent antifungal" as it digests flour - i.e., a mould inhibitor. A link on this can be found here
It remains a mystery as to why only certain wild yeasts and bacteria remain (out of the thousands available in any given environment) in the solution (culture) capable of producing bread. Hopefully, more on this as information comes to hand.
19 Jan 2016 - It is becoming increasingly clear that high fibre diets (and by high fibre I mean brans (e.g., oat bran), beans, berries, whole grains, nuts, greens etc.) are very good for you. For example, reduced coronary and diabetic risk, increased longevity. The latest finding is that people who eat a lot of fibre will have a sleep that is more refreshing, primarily due to the (relative) greater amounts of slow wave sleep.
12 Jan 2016. It has now been scientifically established that naturally leavened (sourdough) bread, through its fermentation of the flour, decreases (at least) the concentration of gluten.
This evidence has been strongly supported anecdotally. As one example, the wife of one of the top sourdough bakers in America (Chad Robertson) had gluten sensitivity and for many years had not eaten her husband's bread. However, after being challenged by Michael Pollan one night to eat a bread made using natural leaven techniques, she took home a loaf, and, determined to expose the truth in the matter, ate an entire half by herself. The result? Nothing. Therefore she continued to eat bread until it almost became an obsession. ... Of course, then she cut back, but the point is ...
The Guardian provides a good overview of the relationship between sourdough breads and gluten intolerance. The Business Insider also has a good analysis of the situation, complete with supporting references.
Many references and data can be found (search the internet) on the fact that sourdough breads are abundant in nutrients, fatty acids, minerals and are easily digestible - to such an extent that gluten sensitives are able to eat it.
4 Jan 2016 - The western world (or cultures adopting same) is increasingly plagued by allergies and auto-immune diseases. It is now believed that the rising incidences of Celiac Disease and wheat sensitivity (1-10% of population, inclusive) is related to the health of the immune system. Given this possible relationship, anything that strengthens the immune system can only be to the good. The research cited here is finding evidence that exercise in the young strengthens the immune system for life. There is an optimal 'window of opportunity' suspected, however, scientists have not yet uncovered the timings.
2013 - Gluten intolerance and the immune system.
The following is an intriguing study relating to the gluten question. A more contextual description can be found in an article from the New York Times, here.
Karelia, once a single province, was bisected with Russia on one side and Finland on the other. The peoples on one side became poor and impoverished (Russia) while the other were exposed to all the benefits of a western standard of living.
This division provided a unique opportunity to examine celiac disease as the two populations, while socio-economically dissimilar, have similar genes and are exposed to similar wheat varieties. One would have thought that the incidence of celiac disease would be equivalent in both populations, particularly if one supports the argument that the increase in gluten related problems is due to the the human species not being properly adapted to eating wheat.)
In 2008, this research was conducted by professors at the University of Tampere in Finland (here). What they found was that the Russians had less celiac disease. Analysis of house dust and potable water suggested that the Russian Karelians encountered a greater variety and quantity of microbes. After a variety of tests, the authors concluded that the Russians have a stronger immune system. Fasano (2012, and a long interview here) has also demonstrated that western life-style countries have a far greater incidence of auto immune diseases (if the target is the brain, then multiple sclerosis; if the joints, then rheumatoid arthritis; the pancreas, diabetes, and in the intestines, celiac disease) than do developing nations.
Note - interestingly, celiac disease is the only autoimmune disease for which the environmental trigger is known (i.e., gluten).
2008 - SOURDOUGH BREADS PRODUCE LOWEST BLOOD SUGAR LEVELS. Professor Terry Graham of the University of Guelph examined four breads and the resulting blood sugar level after ingestion. Of the four breads, only one was a sourdough (made with white flour). The remaining three, using white, whole wheat, and whole wheat with barley flours were made using commercial yeast. He found that the sourdough produced the lowest blood sugar levels, and this effect lasted for hours.
FODMAPs (a complex group of carbohydrates) have been found to be the real cause of Non Celiac Gluten Sensitivity (NCGS)? Michael Specter provides a good summary of this latest research in his article Against the Grain, in the New Yorker magazine.