Monday, November 30, 2009

Gastric bypass stops appetite? Not according to this study


Remember all the articles about how since gastric bypass patients have less ghrelin in their blood, their appetites are curved?

What they all DIDN'T say is this was a theory. In fact, they have not really figured out what ghrelin does in humans but they know it doesn't work the same way in humans as it does in rats (well you may think some humans are rats but they aren't really!) :)

Recently a clinical study seemed to suggest the opposite... not only did the gastric bypass patients not experience appetite suppression but actually a goodly percentage of those in the study (63 patients) became extremely hungry soon after eating!

A clinical study is the most accurate study there is because this is the type of study where the cohort (participants in the study) are physically examined!

This was not a published study but was reported to the convention of the Professional organization for weight loss surgery surgeons, the ASMBS this past summer.

Here is an article I sent out about this:

After the big news stories claiming that gastric bypass patients have less grehlin which causes appetite suppression, a clinical study of 63 gastric bypass patients by Mitchell Roslin and associates, has suggested this theory is in error, when it found that not only did 80 percent of the gastric bypass patients in their study suffer a ravenous appetite soon after meals, but also experienced the almost uncontrollable urge to eat which did for many result in weight regain after the first year (the study went for 4 years).

The researchers also found that 80 percent of the patients also had undiagnosed "glucose abnormalities" including "high blood sugar" or "low blood sugar" or both. Dr. Roslin reported on this study at the 2009 ASMBS convention, suggesting that the gastric bypass may cause a heightened insulin response due to the rapid emptying of the pouch into the small bowel.

All this caused the researchers to wonder whether the gastric bypass should continue to be the "gold standard" of weight loss surgery.

Roslin's theory is that gastric bypass causes an enhanced insulin response due to the rapid emptying of the pouch.

This may in time, make things difficult for diabetics rather than "cure" them as has been advertised on TV. In truth, many gastric bypass patients find after a few years that they again require their diabetes medication.

This study suggests the gastric bypass might undermine their lessened intake of calories rather than help (most diabetics can keep their sugar levels at normal if they restrict calories slightly.


http://www.medpagetoday.com/MeetingCoverage/ASMBS/14874


Bottom line, don't expect a gastric bypass to kill your appetite except during the healing phase (usually takes about a year but some patients heal faster). After that, if you are like many patients, your appetite may not only return but be stronger than it was before surgery.

1 comment:

wriggles said...

80 percent of the gastric bypass patients in their study suffer a ravenous appetite soon after meals, but also experienced the almost uncontrollable urge to eat which did for many result in weight regain after the first year (the study went for 4 years).

I've been geniunely astounded that it could be any other way.

My only coda was in the light of the huge tremendous multiple shock the body undergoes with GBS, that this might temper the appetite, temporarily.

As for the gherlin thing, they say it lessens appetite, but if it is part of a chemical messaging system that in itself signals hunger/ appetite, then attacking appetite/hunger would mean there was less of it!

Less appetite/hunger, less signs of appetite/hunger.

This kind of mindwarp seems to come from the insistence that fatness is a disease. The use of the disease model often seems to get in the way of rational understanding in this way.