After watching the recent BBC programme ‘the truth about fat’ Ghrelin was talked about in relation to hunger, appetite and obesity. Many people may not have heard about this ‘hunger hormone’ so I thought I would cover off a few things.
Ghrelin: a 28-amino-acid peptide hormone that is secreted primarily by stomach cells with lesser amounts secreted by other cells (as of the hypothalamus), that is a growth hormone secretagogue, and that has been implicated in the stimulation of fat storage and food intake
The ghrelin hormone, secreted from the pituitary gland in the brain not only stimulates the brain giving rise to an increase in appetite, but also encourages the accumulation of lipids in visceral fatty tissue, located in the abdominal zone and considered to be the most harmful.
Ghrelin is a hormone produced in the stomach and the function of which is to tell the brain that the body has to be fed. Thus, the level of this secretion increases before eating and decreases after. It is known to be important in the development of obesity, given that, on stimulating the appetite, it encourages an increase in body weight. This accumulated fat in the region of the abdomen that is deemed to be most harmful, visceral obesity being related to higher blood pressure or type 2 diabetes. Being located in the abdominal zone and in direct contact with the liver, this type of fatty tissue encourages the formation of liver fat and increases the risk of developing resistance to insulin.
Research suggests that Ghrelin is closely related to excess weight gain and insulin resistance, particularly under a high fat diet and in the dynamic stage. Controlling this hormone may be useful not only for anorexia-cachexia but also for obesity and type 2 diabetes, which are becoming increasingly prevalent worldwide.
Blocking the body’s response to ghrelin has been suggested as a weight loss treatment but it may also produce unintended effects on mood. The Nature Neuroscience study found mice with increased levels of the hormone showed fewer signs of depression and anxiety. Not all research on ghrelin is as positive and certain.
Experts said further studies were needed.
Meanwhile, get more active and eat a well balanced diet including good sources of protein and you won’t go far wrong!
The science daily (online) 20 May 2009 Merriam-Webster medical dictionary
BBC News online ‘hunger hormone depression link’
British Medical Journal ‘Antagonism of ghrelin receptor reduces food intake and body weight gain in mice’