One of the biggest difficulties faced when losing weight is controlling hunger. After all, the more hungry you are, the more likely you are to indulge in food, increasing your calorie intake and hampering weight loss. If you could control your hunger, would this make losing weight easier? Definitely.
What controls hunger is a fairly complicated topic, if you want to learn about the mechanisms in-depth, then you can head over to my academic series on appetite regulation here. Appetite is the desire to eat, when we have high appetite we will feel hungry and when we have low appetite we feel full.
Trying to lose weight or not, it's important to feel full in-between meals. Not only to reduce excessive eating but to also feel satisfied too. It's certainly not a comfortable experience feeling hungry throughout the day.
What controls appetite?
Appetite is controlled by a seriously impressive and integrated system governed by the brain and gut. Throughout the gastrointestinal tract (GI tract) there are certain hormones that are released that signal to the brain to either increase or decrease appetite (1). These hormones are influenced by different environmental triggers, such as food, exercise and sleep.
Food influences how hungry or full we are. There are many important properties of food that influence how filling it is, such as:
The calorie content
The volume (air & water content)
The nutrient content (carbohydrate, protein and fat)
Fibre is an indigestible form of carbohydrates that passes through the GI tract all the way down to the large intestine (colon). Once fibre reaches the colon, it's greeted by a diverse community of gut bacteria, which ferments fibre into short-chain fatty acids (SCFA)(2).
SCFA are fatty acids whose main responsibility is to provide energy to cells in the GI tract. However, SCFA also signals to the cells in the GI tract to release appetite-suppressing hormones, which then signals to the brain to either suppress appetite (to feel full and stop eating) or stimulate appetite (to feel hungry and begin feeding) (3).
In addition to this, fibre also slows down the digestion of food, a process termed 'delayed gastric emptying'. This is another potential mechanism by which fibre helps keep us feeling full (4).
However, you need to consume enough fibre to experience the appetite suppressing benefits. Research has shown that at least 30g of fibre a day is needed to significantly decrease appetite and subsequently reduce food intake (5).
The best sources of fibre?
Non-starchy vegetables: spinach, kale, broccoli, asparagus
Seeds & nuts: flaxseeds, chia seeds, almonds, cashews
Beans & pulses: lentils, black beans, chickpeas
Most sources of fibre are also fairly large volume or have a high water content, which also makes it that little bit more filling. There's nothing better than heating up some frozen spinach cubes to get the full appetite suppressing effect, bulky, water-dense and packed full of fibre!
Protein has consistently shown across research to reduce appetite and food intake compared to both fat and carbohydrates. This means, when participants are given a high protein meal, compared to high fat or high carbohydrate meal, protein produces a greater reduction in appetite compared to the two other meals, despite all meals containing the same amount of calorie.
How? Well, it seems as though protein increases the production of gut hormones that signal to the brain to make us feel full, explaining the mechanisms of how protein produces these appetite responses (6).
The best sources of protein include:
Meats & fish
Tofu, soy, Quorn
We're all aware of the numerous benefits from exercise, but were you aware of the appetite benefits too?
It seems endurance-based exercises, especially moderate-intensity endurance exercises like running and cycling suppress appetite and reduce food intake. After exercise, hormones that suppress appetite and reduce food intake are elevated, which signal to the brain to keep us feeling full (7).
Can't stop feeling hungry? Why not incorporate some running or cycling, or other forms of activity into your daily routine to get stay full and satisfied?
I'm sure we can all relate to feeling rather grumpy, tired and hungry after a poor nights sleep. After all, we're looking for some quick energy to make us feel more awake and energised, what better place to look than food?
A recent review highlighted how a poor nights sleep can significantly increase appetite, making us feel more hungry the following day. Hormones that make us feel hungry are significantly elevated after less than 5-hours of sleep compared to a healthy nights sleep of 7-8 hours (8).
It's inevitable we'll all experience one or two sleepless nights. Next time, why not start the day with some exercise and pack your plate full of nourishing fibre to not only feel more energised but to feel satisfied and reduce hunger throughout the day.
It's worth mentioning that hunger itself isn't bad! In fact, it's an essential evolutionary drive and it's certainly vital to eat meals throughout the day to provide you with your daily energy requirements. Here, we're talking about the unwanted hunger, and now you have some scientifically proven tips to help tame it:
Incorporate plenty of fibre & protein with each meal, in addition to a healthy serving of fat
30-40 minutes of exercise, with endurance exercises potentially the most effective
A good nights sleep, 7-8 hours!
If you'd like to learn more, or you're interested in booking a consultation with me to help with your health goals, head over to my consultation page here!