From benbrook@hillnet.comSat Mar 29 23:03:37 1997 Date: Sat, 22 Mar 1997 11:14:23 -0500 From: Charles Benbrook To: sanet-mg@amani.ces.ncsu.edu Subject: Food Quality and Soil Health; Response I appreciate Chris Alenson's post of 3/20 re "Food Quality -- A Matter of Taste!" I have no way to prove it, but am certain that the complexity of a crop's growth process has to be reflected in the richness and complexity of its taste. Having just attended Willie's conference and heard lots of related papers, I had a few others ideas and questions that I pass along for anyone to reflect on. We have learned there is more to soil fertility than supplying enough N-P-K, and that the heart of soil quality is microbial biodiversity and activity, as it relates to the N pool, soil structure, root development, and microbial biocontrol of soil pathogens. I takes biological activity in the root zone for the complex communications to occur between soil pathogens, roots, plant immune systems, root exudates, leading to the outcome of a healthy balance in the cropping system. Pathogens persist, but do not overwhelm; roots develop, are attacked, but plants overcome. Then, listening to all the nutrition experts at the Tufts conference generally report a lack of evidence of major differences in the "quality" of food as measured by protein, vitamins, minerals -- the "N-P-K" of the dietary world -- got me to thinking. The human gut is a complex, microbial-dominated ecosystem. The activity of microorganisms in the gut plays a vital role in nutrition because it both determines the bioavailability of various nutrients/minerals, as well as the capacity of the body to deal with various pathogens, carcinogens, mycotoxins, and other poisons we consume in small quantities, everyday. I suspect processes in the gut are also critical in the proper triggering of human immune response to various threats that first enter the body through food and water. Most compounds that trigger hormonal secretions and govern the physiology of the body's basic systems -- day to day respiration, energy metabolism, reproduction and growth, immune response -- are controlled/triggered/regulated by complex protein compounds formed around a mineral base, often iron or zinc. These compounds are called "metalloregulatory compounds," and happen to be structurally similar often in soil and in mammals. There was a great special issue of Science focusing on "Bioinorganic Chemistry" with articles on metalloproteins, metalloenzymes, etc). An article in the issue (Vol. 261, Aug. 6, 1993, page 715) is entitled "Transition Metals in Control of Gene Expression," and describes the role of metals, and complex proteins built around them, in governing the biochemistry and function of the cell, which in turn governs the response to changes in the environment, in food, in disease response, etc. I highly recommend this series of articles to people wanting to delve more deeply into what may be going on with organic systems, food bioavailability, and nutrition/health, and even taste. One of the basic findings across many areas of research discussed in this series of articles is that one of the things that go "wrong" in plant and animal systems is a temporary lack of iron, zinc or other "hub" compounds around which organisms build their metalloregulatory compounds. This is the functional equivalent of not having the building blocks accessible to create enough "on-switches" for the immune system, for example, when a person gets a big dose of a microbial contaminant like salmonella, or exposed to a flu bug, and needs to KICK IN NOW the immune response, to avoid a case of the you know what. So imagine what a basic, homogenized, highly processed, highly sweetened, narrow and biologically "near-dead" diet does to the microflora of the gut? About the same as hot N-P-K fertilizers do to the soil, I suspect. In the gut, this would lead to a lack of efficient capacity to extract iron/zinc where it may be bound in the diet, i.e. these minerals pass through the body unabsorbed to some degree, dampening the body's ability to turn on various systems and responses when it has a signal to do so. Which leads to a number of intriguing questions -- in doing tests of the nutritional/health advantages of organically produced food, maybe we need to test different cohorts -- one people who have eaten "conventional" diets for a long time; another who have eaten more "natural" and biologically active diets, with lots of food grown in alive soil. Wonder if we would learn it is not just what is in the food, but how people are able to use it. Which gets us back to flavor. I also suspect that a persons ability to experience flavors is a function, to some degree of the "gas chromatograph" in their throat, for lack of a more accurate term. I know absolutely nothing about the physiology of taste, but suspect that what is going on in the body's juices, particularly saliva, is going to make a difference re what flavors jump out at a person, and which remain subtle, or not detected. Looking forward to any reflections; we will post the substantive items in this thread on the PMAC web page. chuck Charles Benbrook 202-546-5089 (voice) Benbrook Consulting Services 202-546-5028 (fax) 409 First Street S.E. benbrook@hillnet.com [e-mail] Washington, D.C. 20003 http://www.pmac.net