There could be a REASON why we fail diets. Or -- diets fail us.
One year after initial weight reduction, levels of the circulating mediators of appetite that encourage weight regain after diet-induced weight loss do not revert to the levels recorded before weight loss. Long-term strategies to counteract this change may be needed to prevent obesity relapse.
Ghrelin. You may have heard of this evil little hormone.
Do you follow?
*blink blink* Wikipedia tells me --
Ghrelin is a 28 amino acid peptide and hormone that is produced mainly by P/D1 cells lining the fundus of the human stomach and epsilon cells of the pancreas that stimulates hunger. Ghrelin levels increase before meals and decrease after meals. It is considered the counterpart of the hormone leptin, produced by adipose tissue, which induces satiation when present at higher levels.
In some bariatric procedures, the level of ghrelin is reduced in patients, thus causing satiation before it would normally occur.
Medical News: Hunger Hormones May Be Dieters' Worst Enemy - in Primary Care, Obesity from MedPage Today.
Hormones regulating when a person feels hungry or sated do not rapidly adjust to weight loss, which may be a factor in the yo-yo effect observed among dieters, researchers found.
One year after losing weight, levels of appetite-regulating hormones didn't revert to baseline levels, Joseph Proietto, PhD, of Heidelberg Repatriation Hospital in Australia, and colleagues reported in the Oct. 27 issue of the New England Journal of Medicine.
The findings suggest that the "high rate of relapse among obese people who have lost weight has a strong physiological basis and is not simply the result of the voluntary resumption of old habits," Proietto and colleagues wrote.
It's well established that heavy patients who lose weight dieting often fail to keep the pounds off, the researchers explained.
Studies have shown that restricting calories can lower levels of the hormones leptin -- which tells the brain that the body is full -- and ghrelin -- which stimulates hunger.
Doesn't this also help explain why some forms of weight loss surgery ... work better overall in the long term? In certain types of WLS -- most of ghrelin producing factor -- is removed.
Go DS. Or not. It's up to you. Surgery flame wars!
Approximately 70% of the stomach is removed along the greater curvature, also called a vertical sleeve gastrectomy (VSG). The remaining stomach is fully functioning, banana shaped and about 3 - 5 oz in size which restricts the amount you can consume. The pylorus continues to control the stomach emptying into the small intestine; as a result patients do not experience "dumping". The upper portion of the duodenum remains in use; food digests to an absorbable consistency in the stomach before moving into the small intestine. This allows for better absorption of nutrients like vitamin B12, calcium, iron and protein when compared to gastric bypass procedures.
A benefit of removing a portion of the stomach is that it also greatly reduces the amount of ghrelin producing tissue and amount of acid in the stomach.
Ghrelin is the "hunger hormone" and by reducing the amount of the hormone produced the appetite is suppressed.