Bread: The Staff of Life or What’s Making you Sick?
The Egyptians paid it as wages. To the Romans it was a form of dole. Starved of it, French peasants made a revolution. Bread, symbolic of life in sacred ceremony and folk tradition, was the world’s first “convenience food”, produced on a large scale to feed an industrial workforce bereft of the wherewithal for home baking. Refined, white and cheap, it has penetrated food cultures without anyone paying much attention: the bland leading the blind.
Modern versus traditional
Modern bread is different in several respects from all the bread ever consumed by human beings until at least the latter half of the nineteenth century. The grain, the method of milling and the way the flour is turned into bread — all have changed in response to the economic pressures of industrialization and technological developments in plant breeding, agronomy, milling and baking. The effect of these changes has been to make the majority of bread consumed in Britain certainly less healthy than it could be for all consumers and actually harmful to some. Research is revealing that wheat allergies and intolerances affect much larger numbers of people than the 1% or so who are known to be coeliacs.
Intolerance and sensitivity
In 2000 a Scandinavian study of people presenting with abdominal complaints after eating cereals found positive reactions to cereal allergy tests in 20%. The research clearly identified a wheat sensitivity that is different from celiac disease. There is even a condition known as “wheat-dependent exercise-induced anaphylaxis.” It seems that wheat intolerance is a pyramid, with coeliacs at the top and a progressively larger number of people below with a less drastic sensitivity, but one which can nevertheless cause serious discomfort. The question to which we urgently need an answer is: what have we done to turn bread into something that more and more people choose to, or have to, avoid?
Wheat
Ever since early wheat species emerged from North West India and Ethiopia over 8,000 years ago, the nature of the plant has been evolving. Climate and soil were the main determinants and for most of history farmers could do little more than choose from variations that occurred through environmental pressure and chance mutations. The advent of Mendelian genetics and industrialization eventually changed plant breeding in two respects. First, breeders developed more aggressive methods to force mutations or create crosses and hybrids. Second, with the intensification of farming, especially after the second world war, wheat varieties were selected according to radically new criteria — yield, short straw length (because chemical fertilisers make tall plants flabby and prone to “lodging”), resistance to pests and fungal disease (because natural resistance is lowered by intensive methods) and milling quality (protein level and gluten strength) as defined by industrial bakers who want the stretchiest dough possible. Notice the absence of human nutrition in this list. In fact, nutrition has been of interest to plant breeders only in relation to animal feed grains. It seems certain that the nutritional quality of wheat has suffered. We know that the best traditional varieties of wheat have twice the iron and zinc of modern hybrids and a recent French study revealed that the mineral content of current French wheat is 30-40% below that of older varieties.
Mineral deficiency
Dr Howarth Bouis of the International Food Policy Research Institute states that “over half of the world’s population” is affected by micronutrient deficiencies. Not all of these people are the poor of developing countries. For those on the limits of food security, or on the verge of obesity, the nutrient density of each grain of wheat and therefore each mouthful of bread, affects their health chances.
Anti-nutrients
And that’s not all. As well as lowering mineral content, plant breeders may inadvertently have increased the levels of potential anti-nutrients in wheat. The bread-making quality of wheat (i.e., its ability to make a stretchy dough) is related to its protein content and, in particular, to certain fractions of gliadin and glutenin within the protein. In selecting wheat to make “better” dough, the breeders seem to have increased the levels of those gliadins and glutenins that are most problematic for coeliacs and those with wheat intolerance.
Milling
Until the widespread adoption of roller milling in the 1870s, all flour was produced by crushing wheat between revolving stones. Whereas stone milling followed by sieving had generally “extracted” a white flour consisting of 75-80% of the original wheat, roller milling reduced this to 70-73%.
Nutrient Loss
In refining whole wheat to 70% extraction white flour, many important vitamins and minerals are seriously depleted. For example, vitamin B1 declines by 77%, B2 by 80%, E by 86%, calcium by 60%, magnesium by 84%, iron by 76% and zinc by 78%.1
Four nutrients — calcium, iron, vitamin B1 and nicotinamide — are by law put back into white flour from extraneous sources, though not all at the levels found in whole wheat. However, several of the nutrients that are not replaced are now known to be of considerable importance to health, notably vitamin E, zinc and magnesium (women of all social groups in the UK consume less than the recommended amount). A recent study of different growing and milling methods has shown that stone-ground organic flour has 50% more magnesium and 46% more zinc than roller-milled non-organic flour.
The industrial millers (and their baker clients) try to divert attention away from the nutritional poverty of standard white flour by talking up their ‘healthy eating’ brands, which are fortified with this or that added nutrient. But, given the likelihood that those most at danger of diet-related ill-health are also most likely to be consumers of the cheapest flour and bread, the challenge to the millers is to make all their products healthier. They could start by ensuring that their roller-milled white flour was as nutritious as its stoneg-round equivalent.
Baking
Whatever the plant breeders, farmers and millers have done to the grain, the industrial bakers seem to have made things worse. The so-called Chorleywood Bread Process (CBP), invented in 1961, is used to make 80% of British bread (and much of the rest uses similar additives). The CBP departed from traditional methods by using a good deal more yeast (three or four times as much as before), a clutch of chemical additives and enzymes and little or no fermentation time. Few researchers have asked what effect such changes may have had on the digestibility of bread.
Additives and enzymes
From the poisons and adulterants of the eighteenth century to the ‘crumb softeners’ of today, bakers have constantly sought to extract more “value” from flour than it seemed prepared to give. Over the years the list of permitted additives has reduced (as have sales of the bread they modify), each supposedly essential and “generally-regarded-as-safe” agent eventually proving to be a danger to human health. The most recent to go (apart from flour bleaching in 1999) was the oxidizing agent (and carcinogen) potassium bromate. The chemistry set of additives has, over the past fifteen years, been largely replaced by enzymes. You won’t see them listed on bread labels, because the law treats them as ‘processing aids’, which do not have to be declared. Enzymes can be allergens and should be identified on labels in the same way as the major allergen groups. Failure to label enzymes prevents people from making informed ethical choices over what they eat; many enzymes are now genetically modified and at least one listed in a standard work on the subject is derived from the pancreas of pigs. Most worryingly, recent research indicates that one enzyme quite widely used in the food industry — transglutaminase — can generate in the human gut the epitope of gliadin that is toxic to people with coeliac disease and other intolerances.2
Time and lactic acid bacteria
In reducing fermentation time to zero, modern bakers prevent the formation in dough of certain vital substances: lactic acid bacteria. Although traditional bakers talked of dough being “ripe” to describe the beneficial effect of LAB in long fermentations, it has taken the latest molecular analysis to work out exactly how they work. The results are surprising.
Lactic acid bacteria can improve the “bioavailability” of minerals, lower the glycaemic response (which is good for weight and diabetes control), increase the amount of important vitamins and anti-oxidants and help reduce levels of phytic acid, which can ‘lock up’ certain minerals.
Celiac disease
But most dramatically, Italian scientists3 have demonstrated, in vitro and in vivo, that sourdough lactobacilli are capable of neutralizing completely the gliadin fractions in wheat flour that are toxic to celiacs and people with similar sensitivities. Not only does this open up fruitful opportunities for making wheat breads that can be tolerated by celiacs, but it raises the possibility that it was the move to fast fermentation using commercial yeast and little or no natural lactic acid bacteria which rendered bread indigestible to certain individuals in the first place.
What can be done?
We need to agree on minimum nutritional standards for breadmaking wheat. We need millers to make flours of wide appeal that conserve more of the nutrients naturally present in the grain. And we need industrial bakers to come clean about what really goes into their bread. But, most of all, we urgently need research to compare the digestibility and nutrient availability of fast-made and long-fermented breads. If it turns out that putting the time back into baking (and removing the additives) could make bread good again — even, perhaps, for celiacs — not only would public health improve, but we might learn that the less we try to manipulate food the more likely it is to nourish us.
References:
1Schroeder H. (1971). Losses of vitamins and trace minerals resulting from processing and preservation of foods. Am J Clin Nutr.1971 May;24(5):562-73.
2Gerrard, J. & Sutton, K. (2005). Addition of transglutaminase to cereal products may generate the epitope responsible for coeliac disease. Trends in Food Science & Technology 16 (2005) 510-512. Malandain, H. (2005). Transglutaminases: a meeting point for wheat allergy, celiac disease and food safety. Eur Ann Allergy Clin Immunol 2005: 37:397-403.
3Di Cagno, R. et al (2004). Sourdough bread made from wheat and non-toxic flours and started with selected lactobacilli is tolerated in coeliac sprue patients. Appl. Environ. Microbiol. 2004 Feb; 70(2): 1088-96. Gobetti M., Giuseppe Rizello, C., Di Cagno, R. & De Angelis, M. (2007). Sourdough lactobacilli and celiac disease. Food Microbiol. 2007 Apr;24(2): 187-96. Epub 2006 Sep 12, in process.
