Nutritional measurements

A healthy diet goes a long way in reducing the damage from exposure to lead sources by keeping lead from being absorbed by the body. For a discussion of specific nutritional measures, see Chapter 6. 

Gold, K. 1964. Aspects of marine dinoflagellate nutrition measured by assimilation. J. Protozool. 

Heat is measured in term.s of the calorie, defined as the amount of heat necessary to raise the temperature of 1 gram of water at a pressure of 1 atmosphere firom 15 to 16 °C. This unit is sometimes called the small calorie, or gram calorie, to distinguish it from the large calorie, or kilocalorie, equal to 1000 small calories, which is used in nutritional studies. In mechanical engineering practice in the United States and the United Kingdom, heat is measured in British thermal units (Btu). One Btu is the quantity of heat required to raise the temperature of 1 pound of water 1 ° F and is equal to 252 calories. 

Because overblanching may result in undesirable changes in color, flavor, taste, and texture and the loss of nutritive value, it is as important to avoid overblanching as underblanching. The availability of a method for the detection of overblanching is indicated, but so far as the writer is aware, none exists at the present time. In view of the fact that complete peroxidase inactivation is not required for quality protection, a measurement of residual peroxidase activity might provide the basis for such a test. 

Schoeller, D.A. 1988 Measurement of energy expenditure in free-living humans by using doubly labeled water. Journo/of Nutrition 118 1278-1289. 

Wong, W.W., Cochran, W.J., Klish, W.J., Smith, E.O.B., Lee, L.S. and Klein, P.D. 1988 In vivo isotope-fractionation factors and the measurement of deuterium- and oxygen-18-dilution spaces from plasma, urine, saliva, respiratory water vapor, and carbon dioxide. American Journal of Clinical Nutrition 47 1-6. 

Eleven controlled diet and environment experiments have been designed in a way that can be used to investigate the effects of protein nutrition and heat and/or water stress on diet-tissue A N. Laboratory rats were raised on purified, pelletized diets in which the isotopic composition of proteins, lipids and carbohydrates were well characterized and their proportions accurately and precisely measured (Ambrose and Norr 1993). Four experiments involved manipulation of temperature and/or water availability. Of these four experiments, one used a diet with high (70%) protein concentrations and heat/water stress (36°C) and three used normal (20%) protein concentrations. Seven experiments were conducted at normal temperature (21°C) with water ad libitum. Of these seven experiments, two used diets formulated with veiy low protein (5%), three with normal protein and two with high protein concentrations. 

Although riboflavin is fundamentally involved in metabolism, and deficiencies are found in most countries, it is not fatal as there is very efficient conservation of tissue riboflavin. Riboflavin deficiency is characterized by cheilosis, lingual desquamation and a seborrheic dermatitis. Riboflavin nutritional status is assessed by measurement of the activation of erythrocyte glutathione reductase by FAD added in vitro. 

Klein PD, Roseiand Klein E (1987) Stable isotope usage in developing countries safe trace tools to measure human nutritional status. IAEA Bulletin 4 41-44. 

For regulatory purposes, food-based RMs play an important role in validating accuracy of analytical data from use of routine methodology. For example, the quality of data obtained by analytical measurements serves an important function with regard to ensuring nutritional label claims. Unfortunately, and historically in some cases, assay data for the same analyte can vary greatly from laboratory to laboratory. Evalua-... 

Tanner JT, Wolf WR, and Horwitz W (1995) Nutritional Metrology. The role of reference materials in improving quality of analytical measurements and data on food components. In Greenfield H, ed. Quality and Accessibility of Food-Related Data, pp 99-104. AOAC International, Gaithersburg MD. 

Nonpharmacologic Therapy Pruritus associated with CKD is difficult to alleviate. It is important to evaluate other potential dermatologic causes of pruritus to maximize the potential for relief. Adequate dialysis is generally the first line of treatment in patients with pruritus. However, this has not been shown to decrease the incidence of pruritus significantly. Maintaining proper nutritional intake, especially with regard to dietary phosphorus and protein intake, may lessen the degree or occurrence of pruritus. Patients who do not attain relief from other measures may benefit from ultraviolet B phototherapy. 

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