No abstract

The medical history of salt begins in ancient times and is closely related to different aspects of human history. Salt may be extracted from sea water, mineral deposits, surface encrustations, saline lakes and brine springs. In many inland areas, wood was used as a fuel source for evaporation of brine and this practice led to major deafforestation in central Europe. Salt played a central role in the economies of many regions, and is often reflected in place names. Salt was also used as a basis for population censuses and taxation, and salt monopolies were practised in many states. Salt was sometimes implicated in the outbreak of conflict, e.g. the French Revolution and the Indian War of Independence. Salt has also been invested with many cultural and religious meanings, from the ancient Egyptians to the Middle Ages. Man’s innate appetite for salt may be related to his evolution from predominantly vegetarian anthropoids, and it is noteworthy that those people who live mainly on protein and milk or who drink salty water do not generally salt their food, whereas those who live mainly on vegetables, rice and cereals use much more salt. Medicinal use tended to emphasize the positive aspects of salt, e.g. prevention of putrefaction, reduction of tissue swelling, treatment of diarrhea. Evidence was also available to ancient peoples of its relationship to fertility, particularly in domestic animals. The history of salt thus represents a unique example for studying the impact of a widely used dietary substance on different important aspects of man’s life, including medical philosophy.

Low protein diets, made either of natural foods or of L-essential amino acids and/or their nitrogen-free ketoanalogues, are feasible, safe, and efficient means to reduce disease progression in patients with chronic kidney disease and do not prejudice patient outcomes once they get into Renal Replacement Therapy. They ameliorate symptomatology, grant a positive nitrogen balance, reduce proteinuria, improve osteodystrophy and lipid profile, reduce serum concentrations of uric acid, phosphate, and maintain plasma bicarbonate within normal limits thus preventing metabolic acidosis. They also reduce the number of hypotensive drugs and the quantity of erythropoietin to be administered to achieve target hemoglobin concentrations, and do not deteriorate quality of life. On the contrary, they retard progression of chronic kidney disease. There is a need to motivate patients to increase adherence to.

Thyroid function was measured in 30 healthy subjects and 84 patients with various degrees of nephron loss (GRF: 70 +/- 15 m/min, 30 +/- 16 ml/min, 10 +/- 7 ml/min and 2.1 +/- 1.3 ml/min). A low T3 and T4 syndrome is evident when GRF is reduced to 30 +/- 16 ml/min while a blunted TSH response is detected earlier in the course of nephron loss. T3 response to TRH was normal and FT4 was not affected by renal dysfunction. The data indicate that in nephron loss hypothalamic-pituitary abnormalities occur.