Psyllium Is Superior to Wheat Dextrin for Lowering Elevated Serum Cholesterol Johnson W. McRorie Jr, PhD, FACG, AGAF, FACN Roger D. Gibb, PhD Joyce B. Womack, AS Daniel J. Pambianco, MD, FACG, FASGE The Dietary Reference Intakes for fiber are based on an as- sociation between a high-fiber diet and a reduced risk of cardiovascular disease. Only 5% of Americans consume the recommended levels of dietary fiber; most consume approxi- mately half the recommended level. If a fiber supplement is used to achieve the recommended level, it is important that the isolated fiber has the requisite physical properties to reduce the risk of cardiovascular disease by lowering elevated serum low- density lipoprotein and total cholesterol. The current study was designed to directly assess the cholesterol-lowering effects of psyllium, a natural nonfermented viscous/gel-forming fiber, versus wheat dextrin, a semisynthetic, readily fermented nonviscous supplement. The study was a 3-month, random- ized, parallel-group design (n = 20 enrolled) that assessed psyllium husk (3.4 g) and wheat dextrin (3.5 g) dosed 3 times a day before meals. The results showed that gel-forming psyl- lium significantly (P G .05) lowered both low-density lipo- protein cholesterol ( j17%) and total cholesterol ( j11%), without affecting high-density lipoprotein cholesterol, versus wheat dextrin. In conclusion, clinicians and consumers should be aware that the physical characteristics of a fiber supplement determine whether it will provide specific health benefits, and it is recommended to only take those fiber supplements with evidence of clinically meaningful health benefits from well- controlled clinical studies. Nutr Today. 2017;52(6):289Y294 T he Dietary Reference Intakes for fiber are based on an association between a high-fiber diet and a reduced risk of cardiovascular disease. 1 Note that the recommendation was not based on a reduced risk of constipation or other health effects. In fact, the American Gastroenterological Association concluded that consum- ing a low-fiber diet does not increase the risk of consti- pation: ‘‘Constipation was associated with low dietary fiber intake in some, but not other studies. However, these associations do not necessarily indicate causation. Although it is reasonable to try and modify these risk factors, doing so may not improve bowel function.’’ 2 The Institute of Medicine Adequate Intake guidelines recommend 14 g of dietary fiber per 1000 kcal consumed, which is approx- imately 25 g/d for women and 38 g/d for men (aged 19Y50 years). 1 Unfortunately, only 5% of the US population consumes this level of fiber. 3 The average adult in the United States consumes only 15 g of dietary fiber per day, 3 and those on a low-carbohydrate diet consume less than 10 g/d. 4 If a supplement is being considered to bring fiber consumption up to the recommended level (based on a reduced risk of cardiovascular disease), it is important to recognize that only gel-forming fibers have the requisite physical characteristic to effectively lower elevated blood cholesterol concentrations. It is a misconception that all soluble fibers provide this health benefit. 5 The purpose Nutrition Communications Volume 52, Number 6, November/December 2017 Nutrition Today \ 289 Johnson W. McRorie, Jr, PhD, FACG, AGAF, FACN, completed an associate of arts degree in nursing and worked 14 years as an emergency department/intensive care unit registered nurse, after serving in the US Army (509th Airborne, 221st Military Police). He went on to complete a dual doctor of philosophy degree in neuroscience and physiology at Michigan State University. He is currently a clinical scientist at Global Clinical Sciences, Procter & Gamble, Mason, Ohio, where he has worked for over 20 years. He is a fellow of the American College of Gastroenterology, the American Gastro- enterological Association, and the American College of Nutrition Roger D. Gibb, PhD, completed a BS degree in physics at Utah State University in 1991, an MS degree in biostatistics at The University of Michigan in 1995, and a PhD degree in biostatistics at Virginia Com- monwealth University in 1998. For the following 19 years he has worked as a health care R&D statistician at The Procter and Gamble Company, Mason, Ohio. Quantitative Sciences, Procter & Gamble, Mason, Ohio. Joyce B. Womack, AS, completed an Associates of Science degree in Marketing, graduating Summa Cum Laude in 1989 while working at a wholsale electronics distributor. She continued with that company for the next 8 years, moving up to the position of Executive Vice President before changing careers. She then served as the COO of a leadership/team-building company before taking on the position of Director of Finance of a computer training organization. Ms. Womack then worked in an independent clinical research organization, serving as CEO until she retired in 2016. Since then, she has been providing consulting services to clinical research sites on a part time basis. Charlottesville Medical Research LLC, Virginia. Daniel J. Pambianco, MD, FACG, FASGE, is board certified in internal medicine and gastroenterology and is a Fellow in the American College of Gastroenterology. He is a Certified Physician Investigator by the Academy of Pharmaceutical Physicians and Investigators. Dr. Pambianco was the founder and Medical Director of Charlottesville Medical Research (through 2015), and continues to serve as an Investigator for Gastroenterology- related clinical trials. Charlottesville Medical Research LLC, Virginia. Drs Gibb and McRorie are full-time employees of Procter & Gamble, which markets a fiber supplement (Metamucil). The other authors have no conflicts of interest to disclose. Dr. McRorie is an employee of Procter and Gamble, the producer of Metamucil, a psyllium supplement. He has no other interests to declare. Correspondence: Johnson W. McRorie, Jr, PhD, FACG, AGAF, FACN, Global Clinical Sciences, Procter & Gamble, Mason Business Center, 8700 Mason-Montgomery Rd, Mason, OH 45040 (mcrorie.jw@pg.com). Copyright * 2017 Wolters Kluwer Health, Inc. All rights reserved. DOI: 10.1097/NT.0000000000000243 Copyright © 2017 Wolters Kluwer Health, Inc. All rights reserved.