Trying to lose weight can be frustrating!
When you first start out on your weight loss journey, the weight can come off quite quickly, you might make great progress and feel that your target is more than achievable. But then as the weeks go by the weight loss slows and you have to stay focused to keep the scales moving downwards.
At some point your progress grinds to a halt, or your weight might even go up. You’ve hit a weight loss plateau. You’re doing all the right things just like you did from the start, so what’s going on? Why won’t the weight shift any more?
Or perhaps you lost a lot of weight but put it all back on again, maybe even a little more than before. Why does that happen? Why couldn’t you stay at the reduced weight?
You may have heard of set point theory. This is the idea that your body has a predetermined fatness that it is comfortable with. Any deviation from the set point is accompanied by changes in your biology that will pull you back to the set point. Those changes in your biology are not pseudo-science, they are very real and powerful. They are the reason people plateau or put the weight back on.
In this article I look at the reasons why people plateau or put the weight back on and I list some strategies to prevent that happening. We’ll also discuss the set point idea and look at whether anything can be done to change your set point.
Why have you hit a weight loss plateau?
There are lots of reasons why you will eventually hit a weight loss plateau. Most are associated with reduced energy expenditure. Let’s have a look at them.
You’re eating less
Eating has an energy cost – the thermic effect of food (TEF). When you eat your body uses energy to break down, transport, use and store the nutrients. Most weight loss efforts involve cutting food intake, so of course TEF reduces.
You lose weight
Hang on! That’s the whole point! That’s a good thing isn’t it? Yes, it is, but as you lose weight your Basal Metabolic Rate (BMR) shifts downwards. That means you burn fewer calories at rest which, let’s face it, is most of the day for a lot of people. In other words, you burn most of your daily calories while being inactive, so any reduction in BMR will have a significant impact on your overall energy expenditure.
Your weight also affects your non-resting energy expenditure (NREE). Because you have less weight to move around you burn fewer calories moving around. Non-exercise activity thermogenesis (NEAT) is a major portion of NREE and is the aspect most affected by a reduction in weight.
As your weight comes down, so does your energy expenditure. So, if you start out your programme of weight loss and keep food intake and activity levels the same, even without the other mechanisms outlined below, you will eventually plateau as your energy expenditure lowers to match your food intake.
You become more efficient
Even without exercise, the body becomes more efficient during the weight loss process. It becomes better at using fat and glucose for fuel, meaning less energy than before is needed to perform the same activity.
If exercise is part of your programme, which it should be, then metabolic efficiency is even more enhanced, and movement is more efficient and energy sparing.
You slow down
Alongside metabolic efficiency comes a reduction in sympathetic nervous system activity – this is the part of the nervous system that innervates the muscles, which are a major contributor to energy expenditure. Along with this comes reduced thyroid output, which contributes to a slowed metabolism. Finally, you’ll get reduced sensitivity to adrenaline and increased cortisol leading to reduced testosterone. All this will make you feel sluggish, like you have less vitality. This will undoubtedly impact your tendency to stick to an exercise plan or, if you do exercise, may lead to lower energy expenditure.
At this point, I’d like to quickly mention activity trackers. They are great tools that really help with compliance to a weight loss regime and I think they are pretty accurate. If you can get one with a heart rate measuring LED then it will be a lot more accurate because it should pick up any slow down or changes in efficiency through changes in your heart rate.
You get hungry!
Hormonal changes lead to an increased appetite and reduced sensitivity to the signals of satisfaction from food. On top of this you will become more efficient at clearing nutrients from the blood, leading to earlier than normal hunger signals. Under this pressure, you may not be able to control your calorie intake. Non-compliance to a defined calorie intake is very common.
You may be storing water
If you chart the daily progress of a real weight loss journey, you’ll see it is never a straight line. It goes up and down from day to day but with an underlying trend line that is undoubtedly downwards. What is all this noise on the trendline? It’s not fat, at least not if you’ve been in calorie deficit all that time.
It’s water. The body’s control of fluids is a complex collection of stimuli and hormonal control. Water retention can be affected by salt, carbohydrate, electrolyte balance, dehydration, alcohol, caffeine, stress, certain herbs, fibre, other hormones and so on. Daily fluctuations could be due to the status of any one or more of these factors and the way your body deals with it.
You may retain water for quite a long time before your body decides to get rid of it. There is evidence that water can be stored in fat cells as you lose weight, perhaps in an attempt to retain their size. You therefore appear to stay at the same weight as fat is replaced by water. There’s a popular idea called ‘The Whoosh Effect’, which you can search for, that describes the storage and subsequent release of water from fat cells. There is very little in the way of scientific literature on this, although we have observed something similar in one or two clients.
Why did you lose weight and put it all back on?
You can probably see that some of the changes described above are going to conspire against you when it comes to maintaining a new lower weight.
After weight loss the body is primed for fat storage. It’s sensitivity to insulin is increased and it will store fat very efficiently.
On top of that, changes in hunger and satisfaction signals persist during weight regain, leading to overeating. Couple this overeating with efficient fat storage and you can see that rapid weight regain is common.
It gets worse. Studies suggest that as weight regain begins, new fat cells are created. These fat cells are particularly efficient at storing fat and will eventually become the size of the existing fat cells. After gaining weight you eventually end up at your previous weight, but this time with more fat cells and more capacity to store fat. If you have also lost muscle in the process of weight loss and regain, then you will have a lower BMR than before and are more likely to put a bit extra back on.
I’ve hugely simplified this topic. If you’d like to read more of the science on this then have a look at this excellent review of the physiology of weight loss.
What can you do avoid a weight loss plateau or weight regain?
Keep hold of your muscle
Does that matter? You bet it does! For a start, it burns calories. Research indicates that a large part of the weight-loss reduction in BMR is attributable to a reduction in fat free mass (FFM) – mostly muscle.
But muscle is also the body’s protein reservoir, it helps maintain the health of your organs, it helps with strength and function in everyday life, it strengthens your bones, it helps you adopt good posture and it gives you a better shape. You really should keep hold of it for many good reasons.
But back to calories. Muscle burns calories not just because it is a more active tissue, but because it will help you work harder and lift more in the gym. In terms of resting metabolism, a common estimate is that 1lb of muscle is worth 6 calories a day. It doesn’t sound a lot does it? But it’s easy enough to lose 10lbs of muscle if you adopt the wrong strategies. 10lbs of lost muscle would burn 60 fewer calories per day. Over the course of 5 years, which is a typical timeframe for putting on weight, and using 3500 calories as equivalent to 1lb of fat, that equates to nearly two and a half stone. Ah, ok, so that starts to make muscle loss look like quite a significant concern. You’d better hang on to it then!
We have clients who have lost 30kg on our programmes. With the wrong eating and exercise strategy they could quite easily have lost half of that weight in muscle. That would be 15kg, 33lbs, or 200 calories per day equivalent. Imagine the impact on their metabolism and ability to maintain a new weight?
But surely if I’m exercising, I’m using my muscles and will keep hold of them? Yes, you are, but that’s no guarantee you will hold on to your muscle. The same factors that help you lose fat will also tend to make you lose muscle. A sustained and large calorie deficit will make a dent in your muscle whether you like it or not. But how much of a dent is something you can control. With the right training, the right diet and a moderate calorie deficit, you can minimise muscle loss. Some of our fitter clients who work hard in their sessions and tick all the nutrition boxes actually gain muscle despite losing a significant amount of fat. It can be done. You just have to know how and you have to work hard.
Regular protein and anaerobic exercise – especially weight training – will help safeguard your muscle. I’ve written before about maintaining muscle.
As discussed above, as you lose weight your BMR and your NREE reduce. You can compensate for this by moving more.
First of all, increase your NEAT by just moving around more. Go for walks, do things standing up, use the stairs, do the housework or gardening.
Second, exercise more. After all, if you’re fitter you should be able to. As you lose weight, increase the duration and/or intensity of your exercise. This can be a challenge if your weight loss is making you feel sluggish and with low energy, you may not feel like exercising. For this reason, you might want to try early morning fasted cardio. At this time of day your hormones are in a perfect state for fat mobilisation and oxidation and, crucially, higher cortisol levels should be helping you to release energy, making you feel a bit more energetic. With a shot of caffeine to ramp up adrenaline, you’ll be able to mobilise and oxidise a good amount of fat and burn lots of additional calories so help offset the reduction in NEAT and BMR.
Keep your protein intake up
Get enough, but not too much protein. For starters, you need to get enough protein to help you hold on to your muscle. Second, protein has a much higher energy cost than carbohydrate or fat, so it helps to keep TEF high and compensate for a reduction in TEF due to a lower intake.
That said, more is not better. If you get too much protein your body will get quite good at converting it to use as energy. Not ideal when you want to hold on to your muscle. Also, if you get too much, there’s less room for carbohydrate which has important benefits for metabolism and feelings of wellbeing.
Choose bulky, low calorie foods
Fill your stomach without getting the calories. This means plenty of lean protein, fruit and veg, and plenty of fibre to swell your stomach. This will help to generate better satisfaction signals and take a long time to digest, so delaying the next bout of hunger.
Avoid getting too much fat. There’s very little energy cost of storing fat in fat cells, whereas your body has to use energy to convert excess carbohydrate or protein into fat, so is less inclined to do so. In addition, your fat cells are highly sensitive to insulin after weight loss and so are primed for storage. Fat also gives you a lot of energy without filling you up so it’s less effective at suppressing hunger signals.
Have an occasional carbohydrate refeed
As you lose weight your body becomes more efficient and slows down due to the effects of lower leptin and circulating insulin. You can largely reset the levels of these hormones with a single day of overeating. See figure 4 in the earlier cited excellent review.
This will help reset your energy expenditure. Note that the same effect is not observed with a high fat intake and, for the reasons mentioned in the last section, it’s better to avoid a high fat intake during and after weight loss.
There is one other crucial thing you can do, but first, let’s have an excursion to discuss set point theory.
Are you doomed to gravitate back to your set point?
The idea of a set point has been around for years and is the most well-known model of the mechanism of weight control. It postulates that you have a genetically predetermined set point of fatness and that deviations from that point will produce biological changes that will tend to pull you back to it. So, if you lose weight, you will find that you are predisposed to put the weight back on.
It’s simplistic and doesn’t explain, for example, the obesity epidemic which is a relatively recent development.
There are other models out there too, that all allow for different set points, or varying set points.
Below is my view on the topic. It’s based on my reading of scientific papers and my experience of clients and my own weight maintenance efforts.
If you have been at a certain weight for a long time, that is effectively your current set point. Weight loss will change your biology and tend to pull you back to it. However, if you stick at it and keep up the things that helped you lose weight, you will settle at a new weight and be able to maintain it. I like the general intake model in the cited article for this reason. The simulation performed in this paper showed a settling down at a new weight, provided the revised food intake levels are sustained. Likewise, although not modelled in the paper, any exercise habit that is maintained is likely to result in a new maintained weight.
This is the same as saying that your lifestyle determines where your weight is maintained. If you keep up good exercise and eating habits you will maintain a healthy weight. It’s not rocket science is it?
I would go a little further than that though. Not only will you maintain a healthy weight with the right lifestyle, but that new weight will become your new set point. Or at least your new set point will move closer to your new weight and so exert less of a pull.
Observations of my own weight loss and maintenance efforts seems to support the idea of an adaptable set point. Every year I get down into single digit body fat levels for my competitions. After the final competition of the season I will eat freely and gain weight rapidly. Each year the weight at which I settle gets lower and lower. Last year I maintained 14% body fat throughout the winter. This year I have settled at around 12%.
Bear in mind I am not sedentary, I eat a healthy diet, I work out most days and still do fasted cardio 2 or 3 times a week. In other words, my lifestyle is pretty geared up for maintaining a healthy weight. But my appetite is no longer controlling me like it does just after a competition. In addition, my metabolism seems healthy, I generate a lot of heat and I have plenty of energy. So, it feels like I have settled at this weight as my new set point without an exerting influence of increased hunger and reduced satisfaction signals.
So, all this discussion can be summarised by saying that you can’t simply treat weight loss as a project and revert to your old lifestyle after you reach a target weight. If you do, you can expect to put all the weight back on and possibly more.
During our programmes our clients adopt a new lifestyle. We make sure it works for them and is maintainable. When they get to the end of the programme they don’t need to renew, they just keep doing what they’re doing and maintain a healthy weight for life.
If you want to avoid a weight loss plateau, lose weight and keep it off, you have to change your lifestyle and keep it changed.