If you've ever tried dieting in the past, you know how hard it is to continue losing weight and keep it off in the long run.

In the first few weeks, you tend to lose weight very quickly. But after a few weeks, you might notice the scales come to a complete standstill or the numbers even start to creep back up.

Often when we embark on a weight-loss journey, we assume it’s going to be a linear one. We think we can keep losing weight at the same rate as we did when we first started. But this simply isn’t the case.

Below we can see a graph representing our ‘expectations’ vs the ‘reality’ of a typical weight loss journey:

In the graph on the right, we can see intermittent periods of weight loss and weight plateaus. Although outwardly this might not look ideal, the journey on the right is representative of a more sustainable way to lose weight. Our weight is still trending down overall, but we experience fluctuations and plateaus along the way.

The weight-loss plateaus are important to allow time for our body to ‘reset’ before we can continue losing weight again. This is explained through a theory called the ‘set-point theory’.

Everyone has a natural ‘set point’ which is the weight that our body hovers at when we’re eating healthily. Our set point is determined by our DNA and the environment around us. Slow, gradual weight gain over many years can trick our body into thinking its set point is higher than it should be, which causes our body to resettle at a new, higher weight.

Scientists estimate that the average person will have a set point range of 5-10% of their body weight, which means that at any given time, our body can lose or gain between that amount without much resistance.

If your current ‘set point’ is 12 stone (76kg), this means your body could lose or gain between ~8-17lbs (4-8kg) without too much resistance. But to go below this range would be extremely challenging. Our body is programmed to function optimally within our set-point range and it will do everything to maintain it.

It's important to remember that everyone is unique, so some people might have a different set-point range, meaning their body allows a much smaller or larger weight loss before meeting resistance.

To further explain the ‘set-point’ theory, here's a useful analogy: think of it like our core body temperature. Our body’s normal temperature is 37 degrees. If we go above or below that, the body will do everything in its power to get us back to that optimal temperature – it’ll sweat to cool down or shiver to keep warm. ‘Homeostasis’ is the process by which our body maintains itself in a stable condition, whether it’s temperature or weight.

Set-point theory explains why some people reach a ‘stalemate’ situation when losing weight naturally, despite strictly following the nutrition recommendations.

Our own natural set point might not be what we want it to be, or even what society thinks it should be. Some of us will naturally have a higher set point weight, and some of us will have a lower one.

It’s important to take this into account when making lifestyle changes. If our goal is unrealistic it can be demotivating when it’s not realised quickly enough, resulting in us giving up and returning to our old habits.

You might be asking why you've seen other people lose a lot of weight and never gain it back? The good news is, changing your set point isn’t impossible. But, it takes time.

Just as we can reset our ‘set point’ to be higher when we gain weight, this also works in reverse when we lose weight. But we need to work alongside our body to successfully achieve this. More and more research shows that if we lose weight slowly and gradually, our set point can adjust and our body will stop battling against us.

The ideal weight loss journey will be phased with periods of weight loss and weight maintenance until we reach our goal weight.

Research shows two-thirds of people regain all the weight they lost and then some following a strict diet, so we need to keep in mind that maintaining the weight we’ve already lost is a big achievement.

The weight maintenance phase is essential to allow our body time to adapt. If we ignore this maintenance phase, continuing to lose weight will be a monumental battle.

From an evolutionary point of view, this makes sense. For our ancestors, periods of weight loss generally indicated a risk of starvation due to lack of food availability. Therefore, our body would try its best to hold onto the energy stores that we already have.

This is achieved by lowering our basal metabolic rate (BMR). BMR is a measurement of the amount of energy our body requires to stay functioning at rest. This is how much energy is needed to perform basic functions, like breathing, keeping our heart pumping, and our digestion.

If we’re reducing the amount of energy or fuel that goes into our body, our body will then become much better at rationing what it has to make it last longer. It will reduce our body temperature, thyroid activity, and fat oxidation (or the amount of fat we burn), and help our muscles move more efficiently. All of these adjustments mean that we burn less fuel overall.

To put this into an analogy, our body goes from being a fuel-hungry V8 engine to a fuel-efficient Toyota Prius, without any changes to our body weight.

Research also shows that weight loss increases our ‘hunger hormone’ called ghrelin. The production of this hormone is triggered when the stomach is empty. Once released in the stomach, ghrelin travels to our brain where it signals feelings of physical hunger that trigger us to eat.

Research indicates that people who’ve lost weight have higher levels of ghrelin compared to those who’ve kept the same weight for years. Higher levels of ghrelin also tell our body to conserve more of our fat stores.

Again, this makes sense from an evolutionary point of view, as the body wants to prevent a state of starvation, so it signals for us to eat more to replace the stores we’ve lost.

A period of weight maintenance is important to allow our body’s metabolic rate and ghrelin signalling to readjust back to normal. This happens when our body ‘resets’ to a new, lower set point weight.

This maintenance phase can last anywhere between eight to twelve weeks, but it also varies on an individual level. After this, it’s much easier for us to recommence a period of weight loss.

It's worth highlighting that there may be other reasons (aside from the 'set point theory') that you're experiencing a weight loss plateau or daily fluctuations in your weight.

To find out more about these, you can read the following articles:

Let’s recap the dieting journey some of us may have taken in the past: big initial weight loss, then progress stalls, then progress continues to plateau, and finally we get angry and quit. But the stalling part is so important, the scales aren’t moving because our body is adjusting to change.

We know it’s hard, but once you’ve hit your set-point plateau, your body will need time to adjust to a new weight. Following this, you’ll have established a different set point and your body will respond like that’s the ‘new normal’, which means you can begin losing weight again, if you want or need to.

This is how we can outsmart our body’s set point and continue to lose weight even after we think we’ve reached a plateau.

Sustainable weight loss isn’t a sprint! Most of the time significant life-changing weight loss happens over 1-2 years, not in 1-2 episodes, like on the diet shows on TV. It can take many years for us to gain weight, so likewise it will take time to lose it again.

Remember, slow and steady wins the race!