Paula C. Zemel

Regulation of adiposity by dietary calcium

Recent data from this laboratory demonstrate that increasing adipocyte intracellular Ca2+ results in a coordinated stimulation of lipogenesis and inhibition of lipolysis. We have also noted that increasing dietary calcium of obese patients for 1 year resulted in a 4.9 kg loss of body fat (P<0.01). Accordingly, we tested the possibility that calcitro‐phic hormones may act on adipocytes to increase Ca2+ and lipid metabolism by measuring the effects of 1,25‐(OH)2‐D in primary cultures of human adipocytes, and found significant, sustained increases in intracellular Ca2+ and a corresponding marked inhibition of lipolysis (EC50 ~50 pM; P<0.001), suggesting that dietary calcium could reduce adipocyte mass by suppressing 1,25‐(OH)2‐D. To test this hypothesis, we placed transgenic mice expressing the agouti gene specifically in adipocytes on a low (0.4%) Ca/high fat/high sucrose diet either unsupplemented or with 25 or 50% of the protein replaced by non‐fat dry milk or supplemented to 1.2% Ca with CaCO3 for 6 wk. Weight gain and fat pad mass were reduced by 26–39% by the three high calcium diets (P<0.001). The high calcium diets exerted a corresponding 51% inhibition of adipocyte fatty acid synthase expression and activity (P< 0.002) and stimulation of lipolysis by 3.4‐ to 5.2‐fold (P< 0.015). This concept of calcium modulation of adiposity was further evaluated epi‐demiologically in the NHANES III data set. After controlling for energy intake, relative risk of being in the highest quartile of body fat was set to 1.00 for the lowest quartile of Ca intake and was reduced to 0.75, 0.40, and 0.16 for the second, third, and fourth quartiles, respectively, of calcium intake for women (n=380;P≪ 0.0009); a similar inverse relationship was also noted in men (n=7114; P<0.0006). Thus, increasing dietary calcium suppresses adipocyte in‐tracellular Ca2+ and thereby modulates energy metabolism and attenuates obesity risk.—Zemel, M. B., Shi, H., Greer, B., DiRienzo, D., Zemel, P. C. Regulation of adiposity by dietary calcium. FASEB J. 14, 1132–1138 (2000)

Leadership Profiles of Public Health Nutritionists

Abstract Public health nutritionists (PHN) practice in dynamic and complex organizations. Providing leadership in these types of organizations requires diverse skills. One leadership theory differentiates transactional from transformational leadership. Transactional leaders achieve results by providing and maintaining structure while transformational leaders raise awareness of others and facilitate goal achievement The purpose of this study was to evaluate transactional and transformational leadership roles of PHN. The Competing Values Leadership Profile was completed by 342 PHN in an 8 state region in the southeastern US. This profile included 32 items that assessed frequency of performance of transactional leadership roles (monitor, coordinator, director, producer) and transformational leadership roles (facilitator, mentor, innovator, broker) using a 7-point hedonic scale (7=high) for each item. Differences between role performance was determined by repeated measures analysis of variance. Median experience of PHN was 12 years in nutrition, 7 of that in public health nutrition. Most (74%) had administrative responsibilities. Mean performance scores for transactional roles were: monitor (4.8 ± 1.4), coordinator (5.3 ± 1.4), director (5.0 ± 1.5), and producer (5.1 ± 1). Mean performance scores for transformational roles were: facilitator (5.3 ± 1.4), mentor (5.7 ± 1.3), innovator (4.9 ± 1.1) and broker (4.5 ± 1.3). PHN performed the innovator and broker roles significantly less often than the other 6 roles (p Results suggest that PHN may benefit from professional continuing education and career development opportunities that foster development of innovator and broker roles.

Evaluation of Interactive Video Conferences as a Medium for Professional Continuing Education

Abstract Distance education techniques are increasingly being used to deliver continuing education (CE) to dietetic professionals. The purpose of this project was to evaluate the acceptability of a one-way video, two way audio interactive video conference for professional CE on leadership development for public health nutritionists. The evaluation instrument addressed technical, production and content issues and obtained demographic information from participants. The instrument contained 29 items and used a 5-point hedonic scale for most items. Face validity of the instrument was established by a panel of 3 registered dietitians and 2 teleconference specialists. Evaluations were received from 327 public health nutritionists from 30 sites in an 8 state region in the southeastern US. Most respondents (64%) had worked in public health over 5 years and 74% had administrative responsibilities. Most (70%) spent at least half of their time working with mothers and children. Most participants strongly agreed or agreed that the down link sites were convenient (85%), facilities were appropriate (81%), audio/video reception was clear (88%), video conference length of 3 hours was appropriate (94%), and the format was enjoyable (91%). Most participants strongly agreed or agreed that they had an opportunity to call in with questions during the interactive video conference (77%) and thought visual aids used were helpful (82%). Most participants rated the video conference as very good to excellent (88%). Most participants strongly agreed or agreed that the video conference met its objectives (87%), increased their knowledge and skills in leadership (88%), and developed confidence in their leadership roles (70%). Results indicate that distance learning technology, such as an interactive video conference, is an acceptable medium for providing professional CE to dietetic professionals in public health settings.

A Practical Guide for Estimating Dietary Fat and Fiber Using Limited Food Frequency Data

There are occasions when health promotion programs must be developed based on limited food intake data that are insufficient for estimating dietary fat and fiber intake. Health educators, however, often have sufficient knowledge to evaluate available food intake data as part of a nutrition education needs assessment. A methodology for estimating daily intake of dietary fat and fiber based on limited food frequency data is presented. This procedure involves identifying the medianportion of food items from National Food Consumption Survey data; determining the insoluble fiber and fat content of the food items; multiplying the fiber and fat content of the median portion by the daily consumption rate; summing all items and calculating mean and standard deviationsfor the entire sample. This method can provide baseline estimates of dietary patterns to health promotion policymakers interested in using existingfood intake information.