Calories absorption

Bo-Linn, G., Santa Ana, C., Morawski, S., and Fordstran, J., 1982, Starch blockers - their effect on calorie absorption from a high-starch meal. New Engl. J. Med., 307 1413-1416. 

ALL CHANGES IN PHASE involve a release or absorption of calories. One reason for this is that each solid has its own heat capacity. That is, there is a characteristic heat content for each material which depends upon the atoms composing the solid, the nature of the lattice vibrations within it, and its structure. The total heat content, or enthalpy, of each solid is defined by ... 

The goal is to transition the patient to enteral or oral nutrition and taper off PN as soon as feasible clinically. When initiating enteral or oral nutrition, monitor the patient for glucose, fluid, and electrolyte abnormalities. Perform calorie counts to determine the adequacy of nutrition via the oral or enteral route. When the patient is tolerating more than 50% of total estimated daily calorie and protein requirements via the oral or enteral route, wean PN by about 50%. PN can be stopped once the patient is tolerating more than 75% of total estimated daily calorie and protein requirements via the oral or enteral route, assuming that intestinal absorption is maintained. 

Currently, the only drug on the market that works by blocking the body s absorption of calories is orlistat, which is sold under the brand name Xenical . Orlistat specifically decreases the absorption of fats from food consumed. A further discussion of orlistat and how it works can be found in Chapter 5. 

Although these experiments showed growth was possible using casein hydrolysate, Rose also demonstrated that when the amino acid mixture was used rather than the intact protein, additional calories had to be provided as fat plus carbohydrate, if nitrogen balance was to be maintained. It was later shown that the carbohydrate was needed to protect the free amino acids from oxidation in the intestinal epithelium in the course of absorption. Further, amino acids are poorly tolerated by mouth, causing vomiting and/or diarrhea. After World War II attempts to feed very emaciated prisoners in concentration camps with protein hydrolysates were unsuccessful. It was then recognized that osmotic effects from the amino acids were responsible for the unpleasant consequences. 

Thomsen has shown that this combination, unlike the two previous ones, is not attended with evolution of heat, but by the absorption of it Thus when i gramme of hydrogen combines with 127 grammes of iodine (solid), 6040 gramme-calories of heat are absorbed. 

Abstract Aspartame (Apt), Acesulfame-K (Ace-K) low-calorie, high-potency artificial sweeteners ate cnnently nsed in beverages and dietary food and drinks. Their increased application in food and drink prodncts has given a new impetus to develop fast and accurate methods for their determination. Absorption spectra of Asp, Caf, Ace-K and BA strongly overlap. Therefore a direct determination of these analytes in quaternary mixture is impossible without a separation step. In order to overcome this difficulty partial least squares (PLS) method has been proposed. 

Dietary factors may also be important in gallstone pathogenesis - such as intake of total calories, cholesterol, refined carbohydrates and dietary fibre. As discussed below, the amount of bran, and of other fibre components, in the diet may influence the formation of deoxycholic acid (DCA) in the intestine, its subsequent absorption and its enrichment of bile with DCA conjugates. 

Pharmacokinetics Poorly absorbed after PO administration (absorption increased with high-calorie and high-fat meals). Protein binding 99%. Metabolized in the liver to inactive metabolite. Primarily eliminated in feces. Unknown if removed by hemodialysis. Half-life 13 hr. 

Exothermic Reaction. A reaction in which heat is liberated. It usually proceeds rapidly sometimes explosively. In an endothermic reaction a chemical change proceeds slowly with absorption of a definite number of calories Ref Hackh s (1944), 328-R (Exothermic) 305 R (Endothermic)... 

Weight loss aids Orlistat, 60 mg with each meal containing fat (not to exceed 180 mg/d) Alii Approved for weight loss in overweight adults > 18 years of age when used in combination with a reduced-calorie, low-fat diet and exercise program. Orlistat is a nonsystemically absorbed inhibitor of gastrointestinal lipase that blocks the absorption of dietary fat. OTC formulation is a half-strength version of the prescription product (Xenical). 

Lactitol. Lactitol (4-0-/ -D-galactopyranosyl-D-sorbitol), is a synthetic sugar alcohol produced on reduction of lactose, usually using Raney nickel. It can be crystallized as a mono- or di-hydrate. Lactitol is not metabolized by higher animals it is relatively sweet and hence has potential as a non-nutritive sweetener. It is claimed that lactitol reduces the absorption of sucrose, blood and liver cholesterol levels and to be anticariogenic. It has applications in low-calorie foods (jams, marmalade, chocolate, baked goods) it is non-hygroscopic and can be used to coat moisture-sensitive foods, e.g. sweets. 

The standard or 15" calorie is nnw defined as the rate of absorption of heal per gram per degree at 15°C and in practice is essentially the same as the average caloric over the 1° interval front 14.5 lo I5.5°C. 

Polyols are frequently used sugar substitutes and are particularly suited to situations where their different sensory and functional properties are attractive. In addition to sweetness, some of the polyols have other useful properties. For example, although it contains the same number of calories/gram as other sweeteners, sorbitol is absorbed more slowly from the digestive tract than is sucrose. It is, therefore, useful in making foods intended for special diets. When consumed in large quantities (1-2 oz 25,059 g)/dav, sorbitol can have a laxative effect, apparently because of its comparatively slow intestinal absorption. 

The 5-deiodinase enzyme activity necessary for liver conversion of T-4 into T-3 requires adequate levels of zinc and selenium. During calorie restricted periods lasting more than 2-3 weeks T-4 conversion to the more active T-3 decreases dramatically greatly reducing fat loss. Adequate zinc intake and absorption prevents the decline in 5-deiodinase that causes this negative by about 67% and adequate selenium levels prevents the decline by about 47%. Obviously both in sufficient amounts are best. 

Diet. Diet is shown to affect the absorption, metabolism, and response to many drugs.12,30 Animal and human studies indicated that the total caloric input as well as the percentage of calories obtained from different sources (carbohydrates, proteins, and fats) influence drug pharmacokinetics.17,26 Specific dietary constituents such as cruciferous vegetables and charcoal-broiled beef can also alter drug metabolism.17... 

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