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Why do I gain weight when I eat less?

This blog delves into why the common weight loss advice of "eat less and move more" may not always yield long-term results.

Beth Tripp
Beth Tripp
Why do I gain weight when I eat less?

The common advice to people who want to try to lose weight is to simply “eat less and move more.” Yet, often when people do this, they might lose weight initially, but the weight loss doesn’t seem to continue nor last, leaving them perplexed and wondering “why am I putting on weight even though I’m eating less.”.

Well, there are various other factors that this well-known advice fails to account for, such as metabolism, stress, and sleep, and these factors will be explored in this blog. So, hopefully, you won’t be pondering this question for much longer. So, let’s get into it.

Can eating too little make you gain weight?

We have already touched on the fact many individuals put in considerable effort to lower their calorie intake, only to experience a sense of disappointment when the scale doesn't reflect the expected changes.

Sound familiar?

Unfortunately, reducing calorie intake might not be as straightforward as most people may think, and the weight loss we might have in the short term is not likely to last long. There are various factors that can play a part in why this is often the case. 

4 extra factors that impact weight loss

Nutrition value

The first factor is nutrition.

Simply put, calories do not always equal nutrition, and just because something is lower in calories, it doesn’t always equal nutritionally superior. 

So, maybe you have been having lots of lower-calorie foods that lack much nutritional value when the better choice would have been opting for more whole foods that are higher in calories but in terms of nutrients, you get a bit more bang for your buck. 

A good example of this is foods like avocado. Avocados are a high-calorie food, yet they are a fantastic source of healthy fats, whereas a chocolate bar might be full of additives and sugar, but has fewer calories than the avocado. 

Protein needs

Another common mistake is people simply neglecting food groups like protein as if we aren’t having enough it can mean losing muscle mass. 

Not only that, but sufficient protein intake can also improve our metabolism, which in turn will mean our body will burn fewer calories at rest. So, if we are having fewer calories by sacrificing the protein element of the meal, it might mean we end up burning fewer calories at rest, simply just because our metabolism is slower.

Eating habits

One of the more apparent factors as to why simply eating less doesn’t always work for long-lasting weight loss is that many people will simply eat in a way that isn’t sustainable.

For example, they may not eat enough, or attempt to cut out lots of foods that they enjoy, which results in them not being able to stick to the strict regime they have set out, sending them back into binge eating.

Sleep and exercise

It’s also not just food that can impact weight gain. Factors like lack of sleep and exercise also can impact weight gain. 

What we are trying to say here is if you have tried losing weight by just eating less, there is a reason why it might not be leading to the weight loss you are looking for.

Can eating less affect my energy and metabolism? 

So why can eating less actually lead to weight gain itself?

To answer this, it's essential to consider the impact on energy levels and metabolism. If we greatly reduce our calorie intake, our bodies can take this as a signal that we are going to be in a situation where food is scarce, such as a famine. 

It then decides that because we don’t have access to food, we need to hold onto whatever energy stores we do have. This is because our body is amazing and it can self-regulate, and if we were to find ourselves in an unfortunate situation where food is scarce, we would be very grateful for it.

However, when trying to lose weight by eating less, this biological mechanism can be very counterproductive.

How losing weight can actually lead to weight gain (yes, you read that right)

When your body activates this survival response, it may slow down your metabolism, making it more difficult to burn calories while at rest. Initially, eating fewer calories might seem to lead to short-term weight loss. 

However, over time, your body might interpret the reduced calorie intake as a survival situation and start conserving energy instead of burning it, contrary to your goals. This can lead to a significant rebound effect, where a slower metabolism contributes to not only regaining the lost weight but also potentially gaining additional weight.

On top of this, when we eat less calories, we’re also likely to experience a dip in energy. At the end of the day, food is energy. So if you’re cutting that energy supply it’s going to make completing any form of exercise that bit harder. We all know being physically active is recommended for weight loss, so it’s crucial that we make sure that we have the energy to carry it out. 

To create a sustainable plan that is achievable and doesn’t leave you working a lot harder than you have to, understanding this natural metabolism response is important. 

Why am I gaining weight even though I exercise?

So we have talked about how simply eating less doesn’t result in weight loss, but what about moving more? 

Exercise is often hailed as the silver bullet for weight loss, but there are so many other factors that can influence whether your workout sessions have an effect on the number on the scales.

We might exercise –  which is great – but then eat a lot of calories, or not fuel our body with the right nutrients post-exercise, and these can reduce the calories burnt. 

Many people tend to reward themselves for doing exercise, with sugary and processed foods or use exercise as a way to rationalise eating extra unhealthy foods, and by doing this they might offset any weight loss they would have achieved. Also, as we said before, if you aren’t eating enough, it may slow your metabolism down, meaning that you have to work harder to burn those calories.

The impact of stress and poor sleep

In addition to dietary choices, stress, and sleep play crucial roles in influencing the success of weight loss efforts, particularly in the context of increased physical activity.

You might have heard how stress can lead to increased cortisol.

Cortisol is a hormone associated with the body's "fight or flight" response and if levels are persistently high it may contribute to weight gain by promoting the storage of abdominal fat, as well as trigger emotional eating and cravings for high-calorie and sugary foods. 

Moreover, stress can disrupt sleep patterns, leading to inadequate or poor-quality sleep. Insufficient sleep can disrupt hormonal balance, and this can directly impact our hunger hormones, such as leptin and ghrelin. These are known to regulate hunger and satiety, so if these hormones are out of sorts - it can lead to increased calorie intake. 

There is also the more obvious factor that if you aren’t sleeping well, it may impact motivation to engage in physical activity, therefore burning fewer calories.  

You may be doing the wrong exercise

The very exercise itself can also be inhibiting weight loss. If you are hitting the gym and doing lots of muscle-building exercises, you might be reducing your body weight, but gaining muscle mass. 

This is a really good thing to be building muscle for many reasons, but it will mean that the number on the scale might climb instead of go down. Not only that but if we incorporate a strict exercise routine, there can be some short-term water retention while inflammation goes down and your muscles repair. 

As mentioned, this doesn't mean we should be packing in those weight-lifting sessions just yet, however, some activities do well with weight loss, such as swimming. 

Swimming is extremely beneficial for weight loss, as well as bringing about other benefits such as improving heart health. Dive into our swimming article to discover how you can harness swimming to improve your weight loss.

There isn't a one-size-fits-all approach

So what have we learned here? 

First off, we hope you now understand that with weight loss, there isn’t a one-size-fits-all approach, and there are many different factors that can impact weight. 

Weight loss can be achieved by many more things than simply just reducing the amount of food we eat, whether it’s by:

  • Increasing physical activity levels
  • Getting a regular good night's sleep
  • Adding more whole foods into the diet (like nuts, seeds, beans, and vegetables).

How Embla can help you lose weight

Here at Embla, we know how complex weight loss is and offer personalised support from doctors, nurses, and nutritionists, alongside proven weight loss medication. 

Weight loss medication is a great tool at our disposal to help you achieve lasting weight loss, but to achieve healthy weight loss, it must be coupled with sustainable habits. 

Not only can our health mentors support you in creating these lifestyle changes, but we also have a blog you can read right now on our website on how simple tweaks to your lifestyle can bring about lasting results.

Remember, there is no one-size-fits-all approach, so what might be a sustainable habit for one person, might not be sustainable for another.

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Beth Tripp
Beth Tripp

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