Gastric Bypass Surgery May Alter Brain's Perception of Sweet Taste

photo source:

| Dec 11, 2010

Obese lab rats that have undergone gastric bypass surgery to induce weight loss show a reduced desire for sugar water compared to obese rats that have not had the operation. Researchers at Penn State College of Medicine who observed that outcome also reported that the rats' preferences for salty, sour, or bitter tastes did not change. Lean rats who were given gastric bypass surgery as a control showed no changes in any of their taste preferences.

The results from the school's Department of Neural and Behavioral Science and Surgery indicate that obesity, or becoming obese, may alter the brain's perception of sweetness and the craving for it. If gastric bypass surgery in obese rats somehow changes their brain chemistry and lessens their "sweet tooth," it confirms the same effect that has been noted in post-operative type 2 human patients. 

Previously, scientists thought that changes in humans' preferences for sweets after bypass surgery were the result of increased dietary awareness, as well as motivation supplied by the surgery's often dramatic results. The Penn State College lab rat study opens the possibility that unconscious factors are also working to change perceptions of sweetness.

Gastric bypass involves bypassing a portion of the upper small intestine, either surgically or by implanting a sleeve that blocks off part of the upper small intestine. The process produces a dramatic drop in appetite and weight. Usually applied to the morbidly obese (people with a body mass index of 35 or more), the procedure has produced a high percentage of remissions among recipients who have type 2 diabetes. In many cases, the disease's symptoms disappear within days of successful completion of the surgery.

To prep rats for their study, researchers selected animals lacking a gut hormone, CCK-1, that works to create a feeling of satiation after a meal. Unable to sense when they'd had enough food, the rats ate larger meals than they needed to, eventually becoming obese and developing type 2 diabetes.

Researchers noted that as the rats became fatter, their preference for sweet tastes increased-a tendency also noted in humans who put on large amounts of weight. They observed that taste-receptive neurons in the obese rats' brains responded more energetically to sucrose water than the same neurons in lean rats.

Like their human counterparts, the gastric bypass rats enjoyed dramatic postoperative weight loss-from 26 to 30 percent of their pre-op body weight-and improved glucose tolerance. The surgery also enabled them to maintain long-term weight loss.

While the Penn State College study confirms that obesity creates changes in the brain that trigger an increased preference for sweets, the exact mechanism remains unknown. Beyond that, its findings bolster the case that gastric bypass should become an approved treatment for type 2 diabetes, even in cases where patients are not morbidly obese.

Penn State 




Click Here To View Or Post Comments

Categories: Diabetes, Diabetes, Food, Pre-Diabetes, Research, Type 2 Issues, Weight Loss

Take the Diabetes Health Pump Survey
See What's Inside
Read this FREE issue now
For healthcare professionals only
  • 12th Annual Product Reference Guide
  • Insulin Syringe Chart
  • Insulin Pen Needles Chart
  • Fast-Acting Glucose
  • Sharps Disposal
  • Blood Glucose Meters Chart
  • Insulin Pumps Chart
See the entire table of contents here!

You can view the current or previous issues of Diabetes Health online, in their entirety, anytime you want.
Click Here To View

See if you qualify for our free healthcare professional magazines. Click here to start your application for Pre-Diabetes Health, Diabetes Health Pharmacist and Diabetes Health Professional.

Learn More About the Professional Subscription

Free Diabetes Health e-Newsletter

Top Rated
Print | Email | Share | Comments (0)

You May Also Be Interested In...


Add your comments about this article below. You can add comments as a registered user or anonymously. If you choose to post anonymously your comments will be sent to our moderator for approval before they appear on this page. If you choose to post as a registered user your comments will appear instantly.

When voicing your views via the comment feature, please respect the Diabetes Health community by refraining from comments that could be considered offensive to other people. Diabetes Health reserves the right to remove comments when necessary to maintain the cordial voice of the diabetes community.

For your privacy and protection, we ask that you do not include personal details such as address or telephone number in any comments posted.

Don't have your Diabetes Health Username? Register now and add your comments to all our content.

Have Your Say...

Username: Password:
©1991-2015 Diabetes Health | Home | Privacy | Press | Advertising | Help | Contact Us | Donate | Sitemap

Diabetes Health Medical Disclaimer

The information on this site is not intended or implied to be a substitute for professional medical advice, diagnosis or treatment. All content, including text, graphics, images, and information, contained on or available through this website is for general information purposes only. Opinions expressed here are the opinions of writers, contributors, and commentators, and are not necessarily those of Diabetes Health. Never disregard professional medical advice or delay seeking medical treatment because of something you have read on or accessed through this website.