The Cooper Institute

Founded in 1970 by the "Father of Aerobics"
Kenneth H. Cooper MD, MPH


To Lose Weight, Phone a RD

Posted in
Live well

Monday, Mar 02, 2009

“Phone a friend” is a way contestants on a popular game show recruit help on their quest for a million bucks.  If your goal is to lose weight, then phone a registered dietitian.  

A study published last month in the Annals of Internal Medicine compared different ways for supporting obese men and women in their efforts to lose weight while taking a weight loss medication called sibutramine, otherwise known as Meridia.  Patients were randomized to one of five groups:

  1. Weekly face-to-face meetings with a RD for 3 months followed by bi-weekly face-to-face meetings with a RD (high frequency F2F)
  2. Monthly face-to-face meetings with a RD for 6 months (low frequency F2F)
  3. Weekly telephone calls with a RD for 3 months followed by bi-weekly telephone calls with a RD (high frequency phone)
  4. Weekly email contacts with a RD for 3 months followed by bi-weekly email contacts with a RD (high frequency email)
  5. No contact with a dietitian. (self-help)
All five groups received the same self-help weight loss manual and had access to the same weight loss web site.  And all were prescribed a moderate dose of Meridia.

At the end of the six month intervention, all the groups lost 5% or more of their baseline body weight, a clinically significant finding.  But the high frequency face-to-face and telephone groups lost significantly more weight (8.9% and 7.7% decline from baseline, respectively) than the other groups.  Thus, frequent contact was an important factor, something numerous other studies have shown. 

But this study suggests that meeting with a RD by phone or face-to-face may yield similar results.  The implication being that because phone contact with a RD can be more convenient and less costly than office visits, it may be a good alternative to face-to-face meetings.  Emailing instead of talking live may also be a good delivery option but more research is needed.

This is just one study and like many studies it had some flaws.  For one thing, there was not a group that did not take Meridia so it cannot be determined how much of the weight loss was due to simply to taking the medication.  Also, the patients were nearly all women so the it is not known if similar results would be found for men.

So the next time you want to lose some weight, call a RD instead of phoning a friend.  To find a Registered Dietitian in your area, go to and click on “Find a nutrition professional” in the upper right corner of the web site.  


Digenio AG et al.  comparison of methods for delivering a lifestyle modification program for obese patients.  Annals of Internal Medicine.   2009;150:255-262.