Alterations in the Endogenous Enteric Bacterial Flora and Microbic Permeability of the Intestinal Wall in Relation to the Nutritional and Meteorological Changes
Authors: Arnold Lloyd 
Published: May 2009

There are certain demonstrable changes that take place within the gastrointestinal tract during the process of adaptation to external stimuli. The body as a whole reacts in this adjustment to a changing environment. We have presented our evidence and indicated some instances where these gastrointestinal changes can be considered significant from an epidemiological and preventive medicine standpoint.

The loss of the self-disinfecting power, changes in acid-base equilibrium, and other demonstrable alterations within the lumen of the alimentary tract are only a part of the changes taking place in the organism during the process of adaptation to external environmental changes. If certain diseases are associated with a disturbance of the equilibrium between the parasites and the host, then it naturally follows that we must have more information upon the biological mechanism of the host in regard to its changes in susceptibility and resistance to the parasitic environment. Our present knowledge of bacteriology throws little light upon this epidemiological question. It has been the aim of the author to study the mechanism by which the organism adapts itself to certain environmental changes. We have avoided using pharmacological and other artificial agents that would produce body changes, but have restricted ourselves to simple alterations in diet, external temperature and similar mild or natural environmental factors, and followed the mechanism of adaptation to these physiological stimuli.

The loss of the power of a body-covering layer, to destroy bacteria in contact with it, must increase the hazards of invasion of this body surface by bacteria. We have shown that a sudden change in the intra-intestinal acid-base equilibrium leads to an inhibition of the mucosa to destroy bacteria within its lumen and is accompanied at times by the appearance of viable bacteria in the thoracic duct lymph stream.

If an organism does not adapt itself to its meteorological environment, it is more susceptible to its parasitic environment. The same is true of the nutritional environmental factors. Disturbances due to lack of adaptation to climatic changes can in part be offset by altering the diet. The weather and food factors cannot be separated and one can influence the other.

Changes in climate are beneficial to the well-being of the population living in the temperate zones where meteorological conditions are ever changing as compared to the steady cold in the arctic or constant heat as in the tropics. Changes in food are also beneficial. A high protein meal is stimulating. In the tropics where the skin is in a state of over-stimulation due to the high external temperature and humidity the ingestion of an alcoholic beverage to stimulate the splanchnic system before a meal is beneficial. Acidifying an infant's food in hot weather is a common practice. Many such instances could be cited. It seems to be of advantage to an organism to be in a changing environment. The tonus of our physiological systems is not static or fixed, but is ever changing. The more delicate the index used to measure functional changes, the more frequently are such changes observed. These alterations in environment must not exceed the power of the organism to adapt itself to these changes.