Endocrinology (including Diabetes)/INSULIN THERAPY


Is there any test available to determine in percentage the amount of insulin producing by a  diabetic patient’s Pancrea?If so, what is the name of this test?  Further I want to know the exact time or createria  at which a type 2 diabetic patient is switched into insulin therapy instead of oral medication?  THANKS


I am not a medical doctor, but I will tell you what I know about this topic.  When your pancreas releases insulin, a small peptide gets cut off that is called "C-Peptide."  This can be measured in blood and gives a relative estimation of the amount of insulin your body can make/release.

There is not an exact time for starting on insulin.  Generally, if whatever medication(s) you are on are not keeping your blood glucose in check, another medication can be added.  In the USA, many doctors will add a second or third oral medication if necessary before starting insulin.  Here there are also a number of new types of medications (such as one that makes you lose extra blood glucose via urine) that can also be tried instead of insulin.  I'm not sure what is available in India.  

Hope this helps.  


Endocrinology (including Diabetes)

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Sheri Colberg, PhD


I am an exercise physiologist with a PhD who specializes in diabetes--as such I CANNOT answer general questions about other endocrine problems as I am neither an expert in all areas of endocrinology nor am I a medical doctor. My expertise lies in answering questions about diabetes (of any type) and physical activity, so please limit your questions to those areas. I can help you if you want to begin exercise or if you're already a diabetic athlete, and I am prepared to respond to questions about physical activity to which even your diabetologist may not know the answer. I can give suggestions about changes in your diabetic medications that differing types and intensities of exercise may necessitate, but I will have to refer you to your regular health care team to get final approval to make such changes. I can also answer questions about physical fitness, exercise metabolism, prediabetes reversal, and prevention of type 2 diabetes and diabetic complications.


I have both personal and professional experience in the areas of diabetes and exercise/physical activity. On a personal level, I have had type 1 diabetes since 1968, and I have been an avid exerciser since I was a child. Professionally, I have been conducting clinical studies on diabetes and exercise since 1992, largely with funding from the American Diabetes Association. I am also the author of 8 books related to diabetes, exercise, and more: The Diabetic Athlete (2001), Diabetes-Free Kids (2005), The 7 Step Diabetes Fitness Plan (2006), 50 Secrets of the Longest Living People with Diabetes (2007), The Science of Staying Young (2007), Matt Hoover's Guide to Life, Love, and Losing Weight (2008), Diabetic Athlete's Handbook (2009), and Diabetes? No Problema! (2009).

I am a Fellow of the American College of Sports Medicine, a professional member of the American Diabetes Association (and professional volunteer for the ADA), and a former member of the Board of Directors of the Diabetes Exercise & Sports Association.

I have published research and review articles in the following journals and magazines: Diabetes Care, Diabetes, Journal of Diabetes & Its Complications, Diabetes Self-Management, Medicine & Science in Sports & Exercise, Journal of Applied Physiology, The Physician and Sportsmedicine, Journal of Clinical Investigation, International Journal of Obesity, FASEB Journal, The Diabetes Educator, Journal of Physical Education, Recreation, and Dance, Clinical Exercise Physiology, Clinical Diabetes Reviews, Insulin, ACSM's Health & Fitness Journal, Biomechanics, On the Cutting Edge, Diabetes Technology & Therapeutics, Microvascular Research, Drug Benefit Trends, ACSM Certified News, Diabetes Health, SportEX Health, Diabetes Focus, Diabetes In Control, dLife-For Your Diabetes Life, Pediatrics for Parents, and My TCOYD (Taking Control of Your Diabetes) Newsletter. I have also been interviewed in myriad other magazines, such as Men's Health, Men's Fitness, Diabetes Forecast, Countdown Magazine, Joe Weider's Muscle & Fitness, Health, Tidewater Parent, Barron's News, Diabetes New Day, and Newsweek International.

I have an undergraduate degree (1985) from Stanford University, a Master's degree in exercise physiology (1987) from the University of California, Davis, and a Ph.D. (1992) from the University of California, Berkeley, in the same field. I also spent two years in an NIH-funded postdoctoral research position in endocrinology (studying obesity, diabetes, metabolism, and exercise) at the University of Pittsburgh School of Medicine (1993-1994).

Awards and Honors
• Fellow, American College of Sports Medicine (FACSM) - 1996 • Old Dominion University Darden College of Education Young Investigator Grant Award – 2003 • Honor Society of Phi Kappa Phi, Old Dominion University Chapter – 2004-Present • Great Women of the 21st Century by the American Biographical Institute – 2005 Edition • Old Dominion University Darden College of Education Largest Research Grant Award – 2006 • Old Dominion University Darden College of Education Publications Award (for greatest number) – 2006 • Saint Louis University, The Max K. Horwitt Memorial Lecture Distinguished Lectureship Award – 2008 • Old Dominion University Darden College of Education Publications Award – 2009 • Old Dominion University Darden College of Research Grants Award – 2009

Past/Present Clients
I have consulted for numerous groups, including Can-Am Care, Numera|Social, California Commission on Peace Officer Standards and Training(about candidates with diabetes), Animas Corporation (an insulin pump company), Therasense, Inc. (makers of the Freestyle blood glucose meters), Council of Healthcare Advisors, and the City of Chesapeake (Virginia) Health Department.

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