You've just eaten a large, nutritious dinner and sit down to watch TV, but you're still hungry for something sweet or salty. Really, we should feel full, but our cravings get the best of us and an entire block of chocolate disappears.
There are many reasons we can feel hungry even when we've eaten, from high stress levels to lack of sleep, and it's important to try to identify our triggers in order to stay happy and healthy.
To understand the reasons why we constantly feel hungry or snack endlessly -- as well as find strategies to curb emotional eating and regulate appetite -- HuffPost Australia spoke to Libby Weaver, aka Dr Libby, a leading nutritional biochemist, bestselling author and international speaker.
1. You actually need food
"The first reason is you have a physical need for food," Weaver told HuffPost Australia. "One of the things that signals hunger is when our blood glucose levels start to decrease, so there can of course be a physical reason for hunger."
To discern whether you're physically hungry, look for these tell-tale signs: notice if the hunger comes on slowly (emotional hunger tends to come on quickly), listen for stomach growls, and test if you're still hungry after drinking a big glass of water.
"In that moment ask yourself, 'if I am actually hungry, would I go back and have some more vegetables?' If the answer is 'no', you're probably not hungry."
Solution: eat regular, nutritious meals and snacks throughout the day, and don't skip breakfast.
"And eat more dietary fat from whole food sources, which can make a big difference to what we experience in the evening," Weaver said.
2. You're feeling bored, sad or alone
"Number two would be the many different emotional reasons for hunger," Weaver said.
"If it's sweet food someone wants when they're not really hungry, I'll often use the analogy that they're looking for sweetness in life -- they're looking for joy, for something to look forward to.
"Some people continue to eat after dinner, telling themselves they're hungry, but they are actually trying to numb emotional pain.
"The phrase I tend to use in situations where you feel like you want food, but you know you can't actually be hungry, is: it's never about the food -- it's the way we distance ourselves from the way things are when they're not how we want them to be. It's very difficult in those moments when you really feel like a packet of biscuits to realise this."
Solution: keep a 'what do I really want?' journal.
One strategy Weaver recommends is to keep a notebook to understand why you're experiencing an emotional food craving. To set up the journal, draw four columns: title the first column 'what do I really want?', which is where you write what you're craving. For example, biscuits.
The second column is 'what do you really, really want?'. While your brain may still say 'biscuits' to begin with, if you keep pushing "you realise you might want company, or a hug, or a 'thank you' for washing up every night for the last 18 years".
"The third column is how you perceive having this want -- whether it's the hug, company or 'thank you' -- would make you feel.You might feel appreciated, loved," Weaver said.
"That's actually what you're looking for the food to make you feel, but food can never do that. Food can never tell you that you're appreciated."
The fourth column is 'how do I experience that emotion in a way that's not harmful to my health?'.
"It might be that your children are in bed so you go and watch your children sleep. Or you've got a dear friend who really understands you and you phone her. Or you write in a diary, or exercise, or watch the sunset because it reminds you everything is always okay in the end."
3. You're stressed
Stress is another big cause for always feeling hungry or constant snacking.
"What I mean by that is our stress hormone production: adrenaline and cortisol," Weaver said.
"Science suggests humans have been on the planet for about 150,000 years, and for all of that time adrenaline has communicated to the body that our life is in danger.
"In modern times, we make adrenaline when we consume caffeine and from our perception of pressure and urgency, and the body has not yet learned to decipher the difference between the adrenaline we make from a genuine threat to our life, and the adrenaline we make when we've got six new deadlines on our desk. To your body it's all the same thing."
When our bodies are producing more stress hormones and we have high circulating levels of adrenaline, we require a 'fuel' to power us out of the danger the body thinks it's in. And this affects hunger cues.
"The only two fuels for the body are glucose or fat -- we typically use a combination of both. But when you've got adrenaline you need a fast-burning fuel to get you out of danger," Weaver said.
"The body will get the message to burn glucose -- that is, sugar. Because of the stress response, you will then crave sweet foods to try to top up the stores you've been burning all day."
Solution: practise deep breathing and reduce caffeine intake.
"There's a part of the nervous system that adrenaline drives -- the sympathetic nervous system, which is the fight-or-flight response. Instead of activating that we want to activate the other arm of the nervous system -- the calming arm, which is the parasympathetic nervous system," Weaver explained.
"The only thing science currently knows that will do this is to extend the length of our exhalations. Do a breath-focused practice when you first wake up -- whether it's meditation, tai chi, yoga, pilates or breath awareness."
Alternately, implement moments of 20 long, slow breaths across the day, such as every time you wait at the red traffic lights, make herbal tea or every hour at the computer.
"Get a ritual in your day," Weaver said. "We also have to be honest about how much caffeine we're having and really explore our perception of pressure and urgency."
4. Your food lacks colour, variety and flavour
Humans eat first with their eyes, so if you're used to bland-coloured foods like burgers, chips and biscuits, this lack of colour and variety (and thus lack of sensory sanctification) could be why you're experiencing constant hunger.
"There are definitely people who continue to feel hungry because of a lack of sensory pleasure. If they've had a meal which is really bland, they're going to continue to feel hungry because their senses weren't stimulated," Weaver said.
Solution: eat mindfully and add various colours, flavours and textures to your meals.
"These people do well with really flavoursome foods, lots of herbs and spices, and a variety of colours."
5. You're not sleeping enough
"Sleep has an enormous impact on our appetite. Originally researchers thought that the extra hunger people felt from a lack of sleep was really in search of energy because they were fatigued," Weaver explained.
"What we now understand is that when people don't get enough sleep, the two main hormones that regulate satiety and appetite (leptin and ghrelin) change. You are biochemically driven to want to eat more food when you haven't had enough sleep."
Solution: make sure you're getting eight hours of sleep per night and have a regular bedtime and waking time.
6. You've set up a habit
Another reason we may feel constant hunger, particularly after a filling dinner, is simply habits we have formed over time.
"People do get into real habits of eating dinner and having dessert. Try to recognise when a habit no longer serves your health in any way, and really that's just about making a decision," Weaver said.
Solution: make healthy swaps and eat more dietary fat.
"If you can't stop eating a dessert, it would be wise to make homemade healthy desserts and keep them in the freezer ready to go for the week, so the dessert you have after dinner is a nourishing choice," Weaver said.
"You can make the desserts higher in fat as fat is very satiating, and subtly sweetened with dates, to start to change your habits."
Dr Libby Weaver's new book What Am I Supposed To Eat? launches in all good bookstores from Wednesday 30 August. Weaver commences her national speaking tour 'Food Frustrations' on Monday 4 September.