Alan M. Preston

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This study was designed to determine among various personal, socioeconomic, and environmental factors those which had the greatest influence on exposure to environmental tobacco smoke (ETS) in a population of children residing in a tropical environment and to compare these results with those obtained in the literature of tobacco exposed children in(More)
Although the effects of cigarette smoking on a variety of diseases, from cancer through emphysema and cardiovascular illness are well documented, direct effects on the levels of macro- and micronutrients in the body are reported less frequently. In fact, imbalances in these nutrients may have a role in many of the pathological conditions attributed to(More)
BACKGROUND It is known that vitamin C status is compromised in smokers. The vitamin C status of nonsmokers who are exposed to environmental tobacco smoke (ETS) is now being elucidated. OBJECTIVE We assessed vitamin C status in children who were either exposed or not exposed to ETS, and we sought to associate changes in vitamin C status with the amount of(More)
OBJECTIVE Knowledge of the diet of specific populations is of importance in the assessment of nutrient intake. Herein, we assess the reproducibility and validity of an interviewer-administered food frequency questionnaire (FFQ) in Puerto Rican children at two educational levels--elementary (ES) and high school (HS). METHODS The FFQ contained 97 items(More)
OBJECTIVE Extensive evaluations of the national school lunch program (NSLP) have been carried out on the U.S. mainland. Puerto Rico, a commonwealth of the U.S. is a participant in this program, but has never been included in assessment studies. Herein, we present assessment information and compare results with comparable mainland studies. METHODS Multiple(More)
Tropical sprue is a malabsorption syndrome that responds to treatment with folic acid and a broad-spectrum antibiotic. Eighty years ago, prior to the identification of the vitamins and the discovery of penicillin, clinical trials often consisted of best guess treatments based upon current knowledge and available technology. Dietary interventions were(More)
BACKGROUND Many studies of environmental tobacco smoke (ETS) have been conducted in northern, industrialized countries. As yet, however, no studies have been carried out on ETS exposure with nonsmokers living in tropical environments. METHODS Urine specimens were collected from 175 healthy Puerto Rican children (2-11 years) living in an industrial area(More)
The objective of this study is to determine the influence of several personal and lifestyle factors on the levels of circulating vitamin C in a population of children. To accomplish this objective, blood samples were collected from 511 healthy children residing in the Greater San Juan area. The population was stratified into 4 percentile groups (approaching(More)