Our hunger hormones - how hunger and appetite work

Ever wondered what causes food cravings? 

Or why sometimes you struggle to stop eating, while other times you're perfectly satisfied with just a bit? 

Part of the answer to this actually lies in our hormones - in particular our hunger hormones!! 

While we've been taught to believe that hunger is as simple as calories in and calories out, its actually far more complex than we think... 

Hormones control a HUGE part of how much we want to eat, when we feel hungry, and even what food we choose (or crave) 

Leptin and ghrelin are the two main hunger hormones :

- leptin makes us feel full

- ghrelin makes us feel hungry

LEPTIN is made by fat cells, meaning our fat stores affect how much leptin we make. It's part of the body's 'control mechanism' to regulate our weight.

Leptin  controls hunger, satiety, and even affects our willpower! It speeds up metabolism (via our thyroid) and tells our muscles to burn energy.

Leptin also helps immunity, and rapid weight loss or being underweight makes our immune system weaker, making us more prone to infections. Plus when we lose weight rapidly, leptin levels drop, making it progressively harder to lose more...

It's why crash diets always fail and we end up often regaining more weight, as our hormones start to work against us.

Leptin is also suppressed when we don't get enough sleep - research shows we eat significantly more calories when we're sleep deprived for just a night or two!! 

To optimise leptin, getting enough sleep, managing stress, and avoiding crash diets are all key

GHRELIN does the opposite, it makes us feel hungry, and stimulates our appetite

It's normally released when our body needs more energy, but it's also released when we

✔️see pictures of high calorie food or even imagine this food (which triggers cravings - so don't shop while hungry!! ) 

✔️eat ultraprocessed (junk) food (this stimulates ghrelin release, making us more likely to overeat - research shows people consistently eat more calories when served ultraprocessed meals compared to whole food mels) 

✔️think the food we're eating won't fill us up (this means 'diet' foods often make us feel less satisfied even if they have similar calories)  

✔️are stressed or sleep deprived (those carb and fat cravings when you're tired are real!) 

Ghrelin is suppressed, helping us NOT overeat, when we

✔️eat foods we think will fill us up (ie foods we perceive as filling or satisfying)

✔️eat whole foods (unprocessed - especially high fibre plant foods, these fill us up faster than high fat high sugar foods)

✔️eat off a smaller plate (this tricks our brain into thinking we're eating more!)

✔️wait 15 min before going back for second helpings (it can take this long for our ghrelin levels to drop even when we've eaten enough)

So if you struggle with overeating or controlling those cravings, remember your hunger hormones - and try use these tips to have a healthier relationship with food - they really do work!!