HUNGER & SATIATING HORMONES
Have you ever fascinated with what makes you feel full and hungry? What, when, and how much do we eat?
In this article we will explain about signals and neurotransmitters in the body which lead to feeling full or hungry. Hunger hormones play an important role during those processes.
Signals reach the brain in the hypothalamus region and orders out of it.
There are several well-known hormones that influence appetite, hunger, and satiaty:
- peptide tyrosine tyrosine (PYY)
- glucagon-like-peptide-1 (GLP-1)
- cholescystokinin (CCK)
- Oxyntomodulin (OXM)
In addition, Dopamine that when things go wrong: Eating processed food causes a large surge in dopamine. Continuously eating these foods causes the brain to down regulate dopamine receptors in the brain. Thus we need to eat more and more to get the same fix. Eat processed foods, carbohydrates and sugar sparingly to discourage addiction, cravings and overeating.
During and after feeding state, the production of ghrelin by the stomach is reduced. In comparison, the production of glucagon-like-peptide-1 (GLP-1), cholescystokinin (CCK) and peptide tyrosine tyrosine (PYY) from the gut is upsurged, and the serum leptin levels also increase. The changes send signal to the brain and are detected afterwards, which result in decreased appetite and feeling satiety.
During fasting state, the release of PYY, GLP-1 and CCK from the gut are restrained due to the decreased of food intake. At the same time, the secretion of ghrelin by the stomach gradually increases but serum leptin levels decreases. The changes are detected by the brain, resulting in hunger feeling.
Most satiety hormone’s levels are high in obese, but don’t trigger the brain correctly “less sensitivity”. Furthermore, stomach doesn’t stop secret hungry hormone even in feeding state. Changes can persist for 12 months after initial weight loss and may explain why the majority of obese dieters fail to maintain a reduced body weight.
HUNGER” OR “GORILLA” HORMONE: Keeps you eating until physically full. Released when the stomach is empty and stops when the stomach is stretched. Normally, ghrelin levels are highest before eating and lowest about an hour after you’ve had a meal. However: in overweight and obese people, fasting ghrelin levels are often lower than in people of normal weight. Studies have also shown that after obese people eat a meal, ghrelin only decreases slightly. Because of this, the hypothalamus doesn’t receive as strong of a signal to stop eating, which can lead to overeating.
When things go wrong: Hyperinsulinemia (chronically elevated insulin), insulin resistance, metabolic syndrome, increased hunger and cravings.
Chronically elevated levels of cortisol can lead to overeating and weight gain. However, a strict diet can also raise cortisol. In one study, women who consumed a low-calorie diet had higher cortisol levels and reported feeling more stressed than women who ate a normal diet.
Hormone produced in the brain and nervous system that “stimulates” appetite for carbohydrates. When things go wrong: Stress induces the production of NYP that leads to appetite stimulation and overeating. Fasting and food deprivation can stimulate this hormone.
Both very high and low levels of estrogen can lead to weight gain. During menopause, when estrogen levels drop because less is produced in the ovaries, the site for fat storage shifts from the hips and thighs to visceral fat in the abdomen. This promotes insulin resistance and increases disease risk.
This hormone notifies the hypothalamus (brain) that there is enough fat in storage and prevents overeating. When things go wrong: When impaired signaling doesn’t trigger the brain to calm hunger hormones. This malfunction is linked to obesity, chronically elevated insulin and hypothalamus inflammation.
Peptide tyrosine tyrosine (PYY):
reduces appetite. Insulin resistance and chronically elevated blood sugar impairs production of PYY.
Chronic inflammation reduces GLP-1 production. In one study; men who were given a GLP-1 solution with breakfast reported feeling more satisfied and ended up eating 12% fewer calories at lunch.
CCK is released by duodenum, slows gastric emptying and suppresses energy intake. Irritable bowel syndrome (IBS) can cause an overproduction of CCK that leads to increased prolactin, ACTH and cortisol.
Oxyntomodulin (OXM) is a peptide hormone released from the gut in post-prandial state that activates both the glucagon-like peptide-1 receptor (GLP1R) and the glucagon receptor (GCGR) resulting in superior body weight lowering to selective GLP1R agonists. OXM reduces food intake and increases energy expenditure in humans. While activation of the GCGR increases glucose production posing a hyperglycemic risk, the simultaneous activation of the GLP1R counteracts this effect. Acute OXM infusion improves glucose tolerance in T2DM patients making dual agonists of the GCGR and GLP1R new promising treatments for diabetes and obesity with the potential for weight loss and glucose lowering superior to that of GLP1R agonists.
Proven food & ways to fix the hormones that control your weight:
Protein:Eating protein rich meals is linked to weight loss and the reduction in insulin resistance.
Fat:Omega 3 found in fish can help lower fasting insulin levels.
Greens:Magnesium found in leafy greens can improve insulin sensitivity.
Fiber:Eat foods that have mass to physically stretch the stomach lining.
Avoid white carbohydrates; sugar ….etc, which give calories without stretching the stomach lining. Relax and sleep can help. Focus on anti-inflammatory food like fish meat.
Avoid inflammatory foods: especially sugary drinks and trans fats. Prebiotic, Probiotic supplement increased GLP-1 levels, which led to a reduction in food intake.
Prepared By: Pharmacist. Ruba Noueddin