Provident Perspective Volume 3, Issue 1

Provident News

Welcome to this issue of the Provident Perspective. It has been a busy and productive time for us. We would like to welcome the following people to the Provident team.

• Mona Baker, Support Staff
• Emily Beal, RD. Research Assistant/CRC
• Hillary Feldmeyer-Detty, Support Staff
• Sharon Jackson, Regulatory Specialist
• Jennifer Loux, Research Assistant
• Adam Neiss, Research Assistant

Recent and Upcoming Publications and Presentations

Journal Articles

Maki KC, Carson ML, Miller MP, Turowski M, Wilder D, Reeves MS, Bell M. High-viscosity hydroxypropylmethylcellulose blunts postprandial glucose and insulin responses. Diabetes Care. 2007; (E-pub in advance of publication).

Maki KC, Rains TM, Kaden VN, Raneri KR, Davidson MH. Effects of a reduced glycemic load diet on body weight, body composition and cardiovascular risk markers in overweight and obese men and women. Am J Clin Nutr. 2007; 85:724.

Scientific Meetings

47th Annual Conference on Cardiovascular Disease Epidemiology and Prevention in association with the Council on Nutrition, Physical Activity, and Metabolism. American Heart Association. February 28 - March 2, 2007, Orlando, Florida. Clinical Predictors of Glycosylated Hemoglobin Responses to Thiazolidinedione Therapy. Raquel Izumi, PhD; Janet Hurt, MPH, RD; Kevin C. Maki, PhD; Marjorie Bell; Athanasios I. Zavras, DMD, DrMSc, Mark McCamish, MD, PhD.

23rd American Chemical Society National Meeting. March 25-29, 2007, Chicago, Illinois. High-viscosity hydroxypropylmethylcellulose: A promising agent for metabolic risk factor management. Kevin C. Maki.

Experimental Biology, 2007. April 28 - May 2, Washington D.C.

• Effects of Omega-3-acid Ethyl Esters on LDL Particle Size in Subjects with Hypertriglyceridemia Despite Statin Therapy. Kevin C. Maki, Michael H. Davidson, Harold E. Bays, Evan A. Stein, Robert A. Shalwitz, and Ralph Doyle.
• Vitamin E use and Congestive Heart Failure in the Cardiovascular Health Study. Emily K. Larsen, Kevin C. Maki, Phil Lofgren, Richard Kronmal
• Glucose Tolerance Modifies the Effects of High-viscosity Hydroxypropylmethylcellulose on Postprandial Glucose and Insulin Excursions. Kevin C. Maki. Michael L. Carson, Marvin P. Miller, Maciej Turowski, Marjorie Bell, Donna Wilder, Mathew S. Reeves.

In the Literature

This section of our newsletter briefly reviews one or two recently published papers that may be of interest to our clients.

Maki KC, Rains TM, Kaden VN, Raneri KR, Davidson MH. Effects of a reduced glycemic load diet on body weight, body composition and cardiovascular risk markers in overweight and obese men and women. Am J Clin Nutr 2007;85:724-734.

Methods: This randomized, controlled trial was designed to evaluate the effects of an ad libitum, reduced glycemic load (RGL) diet on body weight, body composition, and cardiovascular risk markers in overweight and obese adults (mean body mass index approximately 32.0 kg/m2) during weight loss (up to 24 weeks) and weight loss maintenance (weeks 24 to 36). RGL subjects were instructed to eat until satisfied, maintaining a low carbohydrate (CHO) intake during the first 2 weeks, then adding low-glycemic index CHO back thereafter. Control subjects were instructed to reduce fat intake and decrease portion sizes, with a targeted energy deficit of 500-800 kcal/d.

Results: Subjects in the RGL group had lost more weight than controls at week 12 (-4.9 vs. -2.5 kg, respectively, p = 0.002), but the two groups did not differ significantly at week 36 (-4.5 vs. -2.6 kg, p = 0.085). At week 12, there were 24 subjects in the RGL group (55%) that achieved a loss of at least 5% of body weight compared with nine (21%) in the control group (p = 0.002), but at week 36, 45% and 29% of subjects were at least 5% below their baseline body weights (RGL vs. control groups, respectively; p = 0.114). Changes in fat mass differed between groups at week 12 (-1.9 vs. -0.9 kg, respectfully, p= 0.016), but not at week 36 (-2.0 vs. -1.3 kg, p = 0.333).

A significant reduction in the RGL group vs. controls was observed for the mean change in total/HDL cholesterol ratio (p = 0.038) at week 12. However by the end of the study, there were no differences in responses for cardiovascular risk markers (fasting lipids, blood pressure, insulin and glucose concentrations) except a larger mean increase in HDL cholesterol in the RGL group (3.8 vs. 1.9 mg/dL, p = 0.037).

Conclusions: The results of this study indicate that among overweight and obese individuals, an ad libitum RGL diet is an efficacious alternative to a low-fat, portion controlled diet. No evidence was present for any unfavorable influence of the RGL diet on the cardiovascular risk profile.

Dr. Maki's Commentary: The results of this trial suggest that a RGL diet may produce more rapid initial losses of body weight and fat than a traditional, low-fat, portion controlled diet. Although the differences between the two dietary approaches narrowed over time and were no longer significant at week 36, it is not clear whether this was a result of compliance drift or due to adaptations to the effects of the two diets on appetite and/or energy expenditure. Additional investigation is needed to clarify the mechanisms responsible for the differential early response to the RGL and portion controlled diets, as well as their persistence with continued consumption over extended periods.

About Provident

Provident has a team of research professionals with extensive experience in the design and conduct of clinical trials to evaluate pharmaceuticals, medical and functional foods, dietary supplements and medical devices.

For more information, visit our web site: http://www.providentcrc.com.

Or, contact us directly:

Tia Rains: trains@providentcrc.com, Director of Medical Writing / Principal Scientist