The Autosow raised miniature swine as a model for assessing the effects of dietary soy trypsin inhibitor.

Toxicological effects of dietary soy trypsin inhibitor (TI) were assessed in male miniature swine, a model chosen for its similarities to human digestive physiology and anatomy. The TI preparation was extracted from defatted raw soy flour. From 1 through 5 weeks of age, piglets were automatically fed either a TI liquid diet [Autosow TI group (ASTI)] or a control liquid diet [Autosow control group (ASC)]. From 6 to 39 weeks of age, these animals received either swine chow and TI or swine chow and control article. The TI diets were formulated to contain a TI activity of approximately 500 mg TI/100 g dry matter. A sow control (SC) group suckled from birth to 6 weeks of age and then fed as the ASC group with swine chow plus control article from 6 to 39 weeks of age. The SC piglets grew faster than ASC piglets during postnatal weeks 1 and 2; however, the ASC piglets were significantly heavier than the SC piglets (P=0.001) at 6 weeks of age. Compared with the ASC group, TI caused a moderate decrease in feed consumption and a moderate but reversible decrease in growth from 2 to 5 weeks of age, but not thereafter. Some control and TI-fed Autosow-reared piglets had loose stools until 6 weeks of age; the effect was significantly greater in the TI-fed group. Otherwise, all swine were active and had normal appearance and behavior.

Saccharin.

Saccharin, a nonnutritive sweetener discovered in 1879, has been the subject of controversy concerning its effect on public health on several occasions during this century. Over this period, the substance has come to be regarded as a useful commodity in the dietary management of diabetes mellitus. We review the historical and scientific background on the subject and propose a new approach in making public-health decisions on unique foods that serve a special dietary purpose.

Nutritional adequacy and safety of infant formulas.

The Infant Formula Act contains specific requirements for minimum and, in some cases, maximum levels for a list of nutrients that may be revised as warranted by the development of new scientific information. Formulas are required to be manufactured in accordance with quality control procedures to ensure that the safety and nutritional potency of a formula is built into the manufacturing process. A formula that does not provide the minimum level for any required nutrient shall be deemed to be adulterated and may be subject to removal from the market. A manufacturer is required to promptly notify the Secretary of the Department of Health and Human Services of instances whereby a formula does not meet the nutrient requirements, is otherwise adulterated or misbranded, and, as such, presents a risk to human health. There are other provisions in the Act, but these establish that, for infant formulas, nutritional safety is clearly recognized as an integral part of food safety.

Sudden death associated with very low calorie weight reduction regimens.

We studied the cases of 17 individuals who died suddenly of ventricular arrhythmia after prolonged use (median 5 months) of very low calorie weight reduction regimens consisting entirely or largely of protein. The deaths appeared to be independent of type of medical supervision received during the diet, daily dosage of potassium supplementation, and biological quality of the protein product used. Factors common to all cases were marked obesity at the onset of dieting, prolonged use of extremely low calorie diets (approximately 300 to 400 kcal daily), and significant and rapid weight loss. Our review of available electrocardiograms and pathological specimens revealed a pattern of cardiac changes previously described in starvation. We conclude that use of very low calorie weight reduction regimens should be curtailed until further studies determine what modifications, if any, can insure their safety.

Is the weight loss of hyperbaric habitation a disorder of osmoregulation?

To examine the weight loss of hyperbaric helium-oxygen habitation, we measured the exchange of liquids and calories in six men who lived in this atmosphere for 32 d. The maximum pressure was 49.5 ATA. The men lost 3.7-10.1 kg, in spite of warm ambient (31-32 degrees C) temperatures and adequate calories (2,737 kcal/d) provided for the sedentary ways of chamber living. Weight loss and a calculated fluid deficit were accompanied by significant hemoconcentration, shown by increases in serum proteins. These changes were followed by a rise in urinary aldosterone and vasopressin, but not thirst. Weight loss in hyperbaric atmospheres is probably multifactorial, but our data suggests an uncoupling of normal osmoregulation may have occurred in the present set of subjects. This may have been due to altered lung mechanics, increased catecholamines, or effects of high pressure on cellular responses to vasopressin.