What are balance studies?

Balance studies are based on the principle of the conservation of energy and matter. In terms of body metabolism, the balance method is simply a comparison of nutrient intake and output (loss from body) and thus is a measurement of body gain or loss.

Metabolic balance studies have been used at least since the 1920s. A thorough accounting of calcium balance methodology was reported in 1945 by a group of authors that included Fuller Albright for whom the highest award given by the American Society for Born and Mineral Research.

Balance studies calculate net retention as intake minus excretion. The technique is applicable only when a stable component is under study or when end products of metabolism are clearly recognized.

For example heat is the end product of energy metabolism and all forms of energy may be expressed as heat. Therefore the balance experiment may be used in studies of energy exchange.

Protein balance is determined by measurement of its metabolically stable component, nitrogen. Balance studies should be performed for several days on a constant protein intake in steady-state conditions.

Mineral elements are stable substances and therefore led to themselves to the balance technique.
What are balance studies?

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Fructose Metabolism

Fructose metabolism occurs mainly in the liver, kidney and small intestine.

Fructose is absorbed rapidly by a carrier mechanism that facilitates transport across the intestinal epithelium; this process is mediated by the glucose transporter isoform, GLUT5 and GLUT2.

Fructose is slowly absorbed, then assimilated in the liver and metabolized by the body, independent of insulin production, and does not cause rapid rises in blood glucose after ingestion.

Therefore fructose does not promote the secretion of insulin.

It is therefore, suitable for diabetics and also for use in drinks intended to act as a lower more sustained energy source.

Owing it to limited effect on blood glucose, it is a low glycaemic index sweetener (compared with glucose).

This is an area of increased nutritional interest and may be a stimulus to the greater use of fructose in drinks.

Three liver enzymes allow fructose to be assimilated into pathways of glycolysis, gluconeogenesis and glycogen synthesis.

Fructose has also been shown to have an increase satiety effect, compared with other sweeteners.

About ten percent of the calories contained in the Western diet are supplied by fructose.
Fructose Metabolism

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