Dr. Joseph Prendergast – ProArgi-9 Plus Expert

Dr. J. Joseph Prendergast

Dr. J. Joseph Prendergast is a distinguished certified physician whose advanced research and experience has contributed significantly to Synergy Worldwide as well as to the medical and scientific fields as a whole. In addition to his role as a practicing physician for over 35 years, Dr. Joe (as he likes to call himself) is an accomplished scientist, researcher, and humanist. His research regarding l-arginine contributed to the development of Synergy’s signature product, ProArgi-9 Plus.

Since 1991, Dr. Joe has been personally using l-arginine and recommending it to his patients. He has become an expert on the many properties and benefits of this amino acid and he understands l-arginine’s essential role in maintaining vital heart health. “L-arginine benefits the body in a myriad of ways,” explains Dr. Joe. “It stimulates the production of nitric oxide in the body, which dilates the blood vessels and helps them relax and restore elasticity. L-arginine is also important in cell division, immunity, and the secretion of hormones. We have now learned more about how l-arginine uses the two natural pathways into the brain to promote anti-aging properties, sports performance, enhance sexual performance, and boost the immune system. We can’t ignore the power of arginine any longer!”

Dr. Joseph Prendergast
• 2008 – ADA “Father of the Year”
• 2005 – AMA Certificate of Recognition
• <1% admissions in 17 years!
• Prestigious Panel Member
• Staff Physician – Stanford

In part due to his use of l-arginine in his clinic, Dr. Joe has a remarkable record of less than 1% patient hospital admissions in 17 years including heart attack or stroke. He has received many awards including “Father of the Year” in 2008 from the American Diabetes Association and the Father’s Day Council of Silicon Valley and a Certificate of Recognition in 2005 from the American Medical Association for demonstrating outstanding commitment to eliminating health care disparities in the area of access.

Dr. Joe is board-certified in internal medicine as well as endocrinology and metabolism. He graduated from Wayne State University in Detroit, Michigan, completed a fellowship in endocrinology and metabolism at Henry Ford Hospital in Detroit, and fulfilled his research fellowship at the University of California, San Francisco. He has served on many prestigious local and national committees and review panels including the American Board of Internal Medicine, the State of California Legislative Task Force on Diabetes and Obesity, and the American Association of Clinical Endocrinologists. Among his many positions, Dr. Joe has served as an Associate Clinical Professor of the Department of Medicine at the University of California Medical Center and is currently a staff physician at Stanford.

Dr. Joe has published 50 medical articles in well-known publications such as the Journal of the American Medical Association and the New England Journal of Medicine and Diabetes Care. In 1986, Dr. Joe formed a single specialty endocrinology practice, Endocrine Metabolic Medical Center, and a non-profit research foundation, Pacific Medical Research Foundation. In 1999, he founded DiabetesWell, an eClinic that helps patients with diabetes lead healthier, longer lives.

From his office in Palo Alto, CA, Dr. Joe sees a variety of patients facing both shortened lifespan and restricted lifestyles. He is one of the foremost practitioners and proponents of l-arginine as a treatment of choice, and through his practice he helps his patients to modify their lifestyles and begin a new, more rewarding life with fewer restrictions and broader opportunities for improvement.

Dr. Joe’s first book, The Uncommon Doctor: Dr. Joe’s Rx for Managing Your Health reveals the secrets of preventive medicine and helps readers design a strategic wellness program, Dr. Joe hosts his own live Internet health program each week.

The preceeding statements are intended to show the opinions and statements of recognized medical professional about L-arginine and ProArgi-9 Plus. They do not reflect any direct endoresment of ProArgi-9 Plus or Synergy Worldwide. All statements are intended to represent the individual as accurately as possible.
Related Information

Dr. Joe Prendergast’s Personal L-Arginine Testimony Video

ProArgi-9 Plus – L-Arginine Complex

ProArgi-9 Plus (L-Arginine) Study


Karen V December 11, 2011 at 9:23 pm

I have been using ProArgi 9 for 2+ years. Originally found out about it from a friend, I have 2 heart valves that have stenosis. In the past 2 years the valves have not changed. Which is good news as this has allowed me to prolong having to have valve replacement surgery. But recently i have been having several episodes of Atrial Fibrillation. I am now taking Tikosyn and Coumadin. My question to you is: Will ProArgi 9 interact with either of these drugs? I will be honest here; I am not sure if the ProArgi 9 is the reason that the valves have not gotten worse but I would prefer not to stop taking it and find out that it is. A prompt answer will be appreciated. I have been on the new medication a week, and have not had been drinking the ProArgi 9. I need to be sure that I will not be interfering with the heart medication or blood thinner. I have not had to use medications in the past and therefore it was not an issue until now.

Appreciate your assistance.

admin December 14, 2011 at 3:13 pm


Thank you for you question and sharing your situation. With a specific condition like yours, I would honestly have to defer you to your cardiologist. As a parent of a child with a valve condition also, I feel it best to bring in the supplement ingredient lists for their review. I will however say that not all doctors (cardiologists or otherwise) are familiar with the recent advances and study results for supplements such as ProArgi-9. This often leads to arrogant or default answers of “I don’t know about it, so don’t take it.”

What you need to understand in making a decision for your self is what is the mechanisms that the supplement affects. L-arginine stimulates the bodies natural production of nitric oxide, a powerful trigger molecule for the bodies repair and replenishment systems. L-arginine is a basic amino acid that helps the body to do what it does naturally. It does not have typical drug interactions like pharmaceuticals because it is a naturally occurring substance, not a synthesized chemical.

People do not get sick because of a drug deficiency. They get sick because of nutritional deficiency (vitamins, minerals, etc). A perfect example of this is the “flu season”. This could more accurately be called “Vitamin D3 deficeincy season”. Winter is the time of less sunshine and outdoor activity. Our exposure to sunlight produces Vitamin D. Lack of sun exposure = lack of Vitamin D. And recent studies continue to show that Vitamin D is significantly better at fighting the flu than the toxic flu shots that are being pedaled as “modern medicine”.

Karen, I do wish you well and hope you can find the information you need here to make a truly informed choice about your needs.

Linda R July 23, 2011 at 1:48 pm

I am not associated with this site, but saw Lisa’s comment and wanted to respond to one specific point — “I am so disappointed with the lack of transparency on the product label with known side effects of sucralose.” Actually, all of Synergy’s product labels clearly state ALL ingredients, including the sucralose contained in the ProArgi-9 Plus’s Citrus Berry flavor. (IMO, among artificial sweeteners, sucralose [Splenda] is probably the safest currently available on the market.) Because some prefer to not use any artificial sweeteners, ProArgi-9 Plus also comes in a Mixed Berry flavor that it sweetened with Stevia (a natural herb).

LIsa DiNardo July 18, 2011 at 9:48 pm

ProArgi ~ 9 Plus Citrus Berry: Sweetner is Sucralose = Chlorinated Sugar = Chlorocarbons: A Metabolic Time Bomb


Greetings Dr. Prendergast,

I’m a very healthy & fit diabetic. Eat healthy and fortified foods, sleep well and play and pray well. I’ve been taking ProArgi 9 Plus Citrus flavor since last fall and I recently learned that sucralose was in the formula. Stunned that the proponents that advocated for me to take it 3 x a day did not know about the artificial sweetner, sucralose in the formula. I am so disappointed with the lack of transparency on the product label with known side effects of sucralose. Why do you advocate putting a Chlorinated Sugar, a synthetic compound, into your perfectly synthesized formula? From what I’ve studied, Sucralose is not nutritionally compatible with the metabolic processes that are ongoing in our bodies. A very sensitive process indeed.

As a scientist and one who is a huge promoter of ProArgi ~ 9 Citrus you are well aware of the health benefits of each and every ingredient. Do you advocate the ingestion of chlorinated foods into our most delicate metabolisms?

I appreciate your time.


Lisa DiNardo

admin July 19, 2011 at 3:07 pm


Thank you for your well thought out and penned comments. I must first tell you that Dr. Prendergast is not associates directly with this site but is rather as a key formulation contributor and ProArgi-9 Plus proponent. If you seek a more direct answer you may be able to reach him through his practice at http://www.endocrinemetabolic.com.

While I can appreciate your concerns I tend to find that there is tremendous amount of research supporting the safe use of sucralose.

Sucralose has been accepted by several national and international food safety regulatory bodies, including the U.S. Food and Drug Administration (FDA), Joint Food and Agriculture Organization / World Health Organization Expert Committee on Food Additives, The European Union’s Scientific Committee on Food, Health Protection Branch of Health and Welfare Canada, and Food Standards Australia-New Zealand (FSANZ). Sucralose is one of two artificial sweeteners ranked as “safe” by the consumer advocacy group Center for Science in the Public Interest. The other is Neotame.[16][17][18] According to the Canadian Diabetes Association, the amount of sucralose that can be consumed on a daily basis over a person’s lifetime without any adverse effects is 9 mg/kg/day.[19][20]
“In determining the safety of sucralose, the FDA reviewed data from more than 110 studies in humans and animals. Many of the studies were designed to identify possible toxic effects, including carcinogenic, reproductive, and neurological effects. No such effects were found, and FDA’s approval is based on the finding that sucralose is safe for human consumption.” For example, McNeil Nutritional LLC studies submitted as part of its U.S. FDA Food Additive Petition 7A3987 indicated that “in the 2-year rodent bioassays…there was no evidence of carcinogenic activity for either sucralose or its hydrolysis products…”[21]

For those who do not wish to take this, the mixed berry flavor was formulated with this in mind and does not contain sucralose.