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G H Beaton

Publications and source records attributed to G H Beaton.

At least 37 records · Page 2Linked to original sources
PubMed1988

Protein requirements of infants: a reexamination of concepts and approaches.

Estimates of protein requirements of infants aged 3-4 mo by FAO/WHO/UNU (1.47 +/- 0.26 g.kg-1.d-1 as crude protein, N X 6.25) are judged to be overestimates. From simulation analyses we suggest that 1.1 +/- 0.1 - 0.2 g.kg-1.d-1 is a more reasonable estimate. This is consistent with statements that 1) breast milk that provides an average of 16 g protein/1000 kcal or a fixed-composition formula that contains 17 g protein/1000 kcal is adequate for essentially all such infants and 2) average protein intakes from that milk or formula would be approximately 1.65 or 1.75 g.kg-1.d-1, close to current average requirements estimates. It appears that there has been a difference in the concepts of requirement usually applied to infants and to adults and a systematic misinterpretation of breast-milk data in estimating requirements. A plea is issued for the application of epidemiologic approaches as a part of requirement estimation.

Dietary Proteins↗
PubMed1986

Evaluation of methods used to assess dietary intake: simulation analyses.

The choice of dietary methodology can affect the ability to detect and describe the relationship between dietary sodium intake and blood pressure. This is illustrated in this paper through the use of simulation modelling of the effect of using different dietary methods (food recalls or records covering different numbers of days, food frequency questionnaire estimates of a single diet component) and using urinary excretion as a proxy for intake. Both epidemiologic studies and experimental interventions are simulated. Although the data base used was simulated rather than real, an attempt was made to keep it realistic in relation to what might be seen in actual populations. From these analyses it can be inferred that with appropriate choice of methodology and study design, even low order relationships between sodium intake and blood pressure should be detectable. At a more general level, it may be concluded that while there is no perfect dietary methodology, there are preferred methodologies for defined purposes.

Adult↗
PubMed1985

Nutritional needs during the first year of life. Some concepts and perspectives.

This article reviews some of the recent changes in thinking that are reflected in two reports (Recommended Nutrient Intakes for Canadians and the FAO/WHO/UNU Report on Energy and Protein Requirements) concerning nutrient requirements for infants below one year of age. The author illustrates the concepts underlying the published requirement estimates and hence some of the principles that should underlie the interpretation and application of the estimates.

Absorption↗
PubMed1983

Source of variance in 24-hour dietary recall data: implications for nutrition study design and interpretation. Carbohydrate sources, vitamins, and minerals.

Beaton et al (Am J Clin Nutr 1979;32:2546-59) reported on the partitioning of variance in 1-day dietary data for the intake of energy, protein, total carbohydrate, total fat, classes of fatty acids, cholesterol, and alcohol. Using the same food intake data and the expanded National Heart, Lung and Blood Institute food composition data base, these analyses of sources of variance have been expanded to include classes of carbohydrate, vitamin A, vitamin C, thiamin, riboflavin, niacin, calcium, iron, total ash, caffeine, and crude fiber. The analyses relate to observed intakes (replicated six times) of 30 adult males and 30 adult females obtained under a paired Graeco-Latin square design with sequence of interview, interviewer, and day of the week as determinants. Neither sequence nor interviewer made consistent contribution to variance. In females, day of the week had a significant effect for several nutrients. The major partitioning of variance was between interindividual variation (between subjects) and intraindividual variation (within subjects) which included both true day-to-day variation in intake and methodological variation. For all except caffeine, the intraindividual variability of 1-day data was larger than the interindividual variability. For vitamin A, almost all of the variance was associated with day-to-day variability. One day data provide a very inadequate estimate of usual intake of individuals. In the design of nutrition studies it is critical that the intended use of dietary data be a major consideration in deciding on methodology. There is no "ideal" dietary method. There may be preferred methods for particular purposes.

Adult↗
PubMed1979

An examination of factors believed to be associated with infantile obesity.

Forty-two normal (25th to 75th percentiles of weight for age) and 47 "obese" (above the 90th percentile) infants, 4 to 9 months of age, were compared with regard to energy and macronutrient intake, breast-feeding history, age of introduction of solids, and maternal reliance on external feeding cues. The study failed to reveal characteristic group differences. The current stereotype of the obese infant as one who is overfed, is given solids very young, is not breast fed, and whose mother is not responsive to his satiety signals is challenged. As a result, the nature of current group counseling for the prevention of infantile obesity is questioned.

Birth Weight↗
PubMed1977

Production of slow alpha2-globulin in the pregnant rat.

Slow alpha2-globulin (salpha2G), a high molecular weight glycoprotein, appears as a component of rat serum in a wide variety of both physiologic and pathologic conditions, including pregnancy; it is also present in the neonate. In the present study, the protein was detectable in serum after 6 to 10 days, and was present at moderate levels on day 13, and thereafter through the rest of pregnancy. From immunofluorescent localization and 14C-labelled amino acid incorporation studies, salpha2G was found to be localized in uterine and placental tissues and to be synthesized by these tissues as early as day 6 of gestation. Production continued throughout pregnancy. Synthesis in the liver of the pregnant rat began at day 17 of gestation, which is in contrast with the observation in pathologic conditions that liver synthesis is an initial source of the serum protein; substantial fetal liver synthesis was occurring at day 21 of gestation, and the amount in fetal serum was four times greater than that in maternal serum at that time. It is likely that the fetal liver produces salpha2G as soon as it begins to function.

Alpha-Globulins↗
PubMed1976

Perspectives and priorities in food and nutrition planning.

I have taken this opportunity to challenge a trend that I have seen in recent meetings toward the promotion of a holistic, but perhaps impractical, approach to food and nutrition policy planning and implementation. While I support the development of modeling as an approach to the conceptualization of the problems and interactions, it would appear that the data requirements of the integrated nutrition policy approach exceed our present capabilities. I fear that this can result in inactivity at a time when we cannot afford inactivity--inactivity consequent to delay for data collection, or inactivity consequent to a belief that because comprehensive planning is not yet feasible, there is no point in doing any systematic planning. The precision of the definition of the nutrition problem is a function of the stage of development of the operational planning process. Let us not advocate the collection of data we are not equipped or prepared to interpret and use. In many areas of the world, relatively simple information, often already available, can define the nutrition problem with sufficient precision to permit program development within the individual sectors of government. Surely that must be our immediate goal.

Child, Preschool↗