Why Diets Fail (And What I’ve Learned About Losing Weight the Hard Way)

I know how to lose weight.

At one point in my life, I was actually very good at it. I lost around 10 stone in 73 weeks, going from 22 stone 12lb to around 12 stone. I followed my plan religiously, watched the numbers on the scales come down and eventually reached the weight I’d spent so long working towards.

If you’d asked me then how to succeed at a diet, I could probably have given you plenty of advice.

Plan your meals. Stay motivated. Don’t give up after a bad day. Drink plenty of water. Find lower-calorie alternatives. Keep going when the scales don’t do what you want them to do.

Some of that advice isn’t necessarily wrong, but I see weight loss very differently now. Because losing the weight wasn’t the end of my story.

I regained weight. My relationship with food and the scales wasn’t always particularly healthy, and some of the things I thought were evidence of being incredibly committed to weight loss are things I would actively discourage now.

That experience has taught me far more about why diets fail than successfully losing the weight ever did.

The biggest lesson has probably been this: being able to lose weight and being able to live at a lower weight for the rest of your life are two very different challenges.

My perspective: I lost around 10 stone in 73 weeks after joining Slimming World, going from 22st 12lb to around 12st. I later regained weight, and my experiences with dieting, maintenance, food and the scales have changed considerably since then. This article isn’t about telling you which diet to follow; it’s about what I’ve learned from experiencing both significant weight loss and weight regain.

Why do diets fail?

I think we often ask the wrong question. When somebody starts yet another diet and eventually stops following it, we tend to ask what went wrong with the person. Why couldn’t they stick to it? Why didn’t they have enough willpower? Why did they let themselves regain the weight? Why can’t they just eat less?

Maybe we should spend a little more time asking whether the way they were trying to lose weight was something they could realistically continue doing.

There are countless diets that can help someone lose weight in the short term. If an eating plan creates an energy deficit and you follow it consistently, weight loss can happen.

The difficult bit is what happens six months, two years or ten years later. That’s where my perspective has changed enormously.

I used to think successful weight loss meant reaching my target. Now I think the real challenge is finding a way of eating, moving and living that doesn’t require your entire life to revolve around maintaining that number.

I thought motivation was the answer

When you first start losing weight, motivation can be incredibly powerful. You might have had a photograph taken that you hate, struggled to fasten an aeroplane seatbelt, received worrying health news or simply reached a point where you desperately want something to change.

That initial burst of motivation can carry you quite a long way. The problem is that nobody remains permanently motivated.

There will eventually be a cold, miserable Wednesday when you don’t particularly care about the inspirational reasons you wrote in a notebook six months ago. You’ll be tired, hungry and fed up, and the novelty of your new weight-loss plan will have disappeared.

If the only thing keeping your diet going is how desperately you want to lose weight, it becomes much harder when that feeling isn’t as strong.

This doesn’t mean motivation is useless. I’ve written separately about how to stay motivated when losing weight, because there are absolutely things that can help. But motivation can’t be the entire foundation.

The things you can do reasonably easily when you’re not feeling motivated are probably much more important.

The diet you can tolerate isn’t necessarily the diet you can live with

This is one of the biggest things I would think about if I were approaching weight loss again.

Ask yourself:

Could I imagine eating roughly like this when I’m no longer actively trying to lose weight?

Not perfectly. Obviously life changes and nobody eats exactly the same meals forever. But broadly. If you’re spending the whole diet looking forward to reaching target so you can stop doing it, that might be telling you something important.

Perhaps you’ve removed all the foods you really enjoy. Maybe you’re avoiding meals out because you can’t control the calories precisely enough, cooking separate dinners from your family or going to bed hungry every evening.

You might be capable of doing those things for three months because losing weight currently feels incredibly important. But could you do them for three years? Ten? That’s a much harder question.

Losing weight quickly can feel incredibly rewarding

I understand the appeal of fast weight loss. When you’re carrying a lot of weight and desperately want it gone, losing half a pound can feel disappointing when you’ve convinced yourself you should be losing three.

I certainly became very focused on getting good results on the scales. The more weight I lost, the more successful I felt. That can make it tempting to eat less and less or become increasingly strict because bigger losses feel like proof you’re doing everything properly. I don’t think like that anymore.

I’d much rather lose weight more slowly while eating enough, enjoying my meals and having a life than lose it incredibly quickly using an approach I’m desperate to escape from.

This is also why comparing your losses with somebody else’s is so unhelpful. Your starting weight, body, activity levels, circumstances and health aren’t identical. Weight loss isn’t a race where the person reaching target first wins.

Being hungry isn’t evidence that you’re doing well

Diet culture has a strange relationship with hunger.

There’s sometimes an assumption that hunger is something you should learn to tolerate. If you’re hungry, apparently you just need more willpower. Drink some water. Distract yourself. Brush your teeth. Go for a walk.

Those things might help when what you’re experiencing is boredom or a habit of reaching for food at a particular time. But sometimes you’re hungry because you need food.

If you’re spending most of the day thinking about your next meal, struggling to concentrate and desperately trying not to eat because you’ve used your calorie allowance, I’d question whether your current approach is going to be sustainable.

Making meals satisfying matters.

Protein, fibre and foods you genuinely enjoy can all make a difference. So can eating enough at meals instead of creating tiny “diet portions” and then wondering why you’re rummaging through the cupboards two hours later.

I’ve written much more about this in my guide to why you might feel hungry all the time, because hunger deserves a better answer than simply telling people to develop more self-control.

Food noise can make dieting even harder

I’ve also become much more aware of the difference between physical hunger and constantly thinking about food.

You can have eaten enough and still find food occupying an enormous amount of mental space.

What am I having for dinner? How many calories is that? Can I have a snack? I shouldn’t have a snack. Maybe I’ll have one later. How many calories have I got left? What am I eating tomorrow? It can be exhausting.

For some people, highly restrictive dieting seems to make that mental chatter even louder because suddenly food has become incredibly important.

When you decide you absolutely cannot have something, there’s a fair chance you’ll spend much more time thinking about it.

I’ve written separately about food noise vs hunger because they’re not quite the same thing, but both matter when you’re trying to understand why sticking rigidly to a diet can feel so difficult.

The “good food” and “bad food” mentality didn’t help me

I used to see food much more in terms of whether it was good or bad for weight loss. Some foods fitted the plan. Others didn’t. If I ate something outside the rules, it was very easy for that decision to feel like I’d done something wrong.

The problem with this kind of thinking is what happens next. You eat something you’ve labelled “bad”. You feel guilty. The day now feels ruined, so you might as well have something else. Perhaps you’ll start again tomorrow, or Monday, or after Christmas.

One food decision turns into several days of eating differently because mentally you’ve already failed. I no longer believe food needs that moral judgement.

Some foods are more nutrient-dense than others. Some contain more calories. Some keep you fuller. Some are mostly there because they taste lovely. That’s okay. Chocolate doesn’t need to pretend to be broccoli before you’re allowed to eat it.

Learning that one food doesn’t have the power to ruin your entire diet makes it much easier to simply enjoy something and carry on.

The scales became far too important to me

This is probably one of the biggest things I would change.

When I was losing weight, weigh-in mattered enormously. Seeing a good loss could make me feel brilliant, whereas a disappointing result could affect how I felt about the entire week.

The problem is that your weight isn’t a weekly performance score.

I’ve recently written in detail about why weight fluctuates, because there are so many reasons the number can change that have nothing to do with suddenly gaining body fat.

Water retention, your menstrual cycle, salt, carbohydrates, food still being digested, constipation and even starting a new exercise routine can all affect your weight temporarily.

I wish I’d understood that emotionally as well as intellectually.

It’s one thing knowing weight can fluctuate. It’s another being able to step off the scales after seeing a gain and genuinely not allow that number to decide whether you’ve succeeded.

The scales can be useful. They just shouldn’t be the judge, jury and executioner of your week.

Trying to be perfect made setbacks feel enormous

Another thing I understand much better now is how dangerous perfection can be when you’re trying to change your habits.

If your goal is to follow your diet perfectly, eventually you’re going to fail. Not because there’s something wrong with you, but because you’re human.

There will be birthdays, holidays, meals out, Christmases, terrible days, unexpected takeaways and evenings when the dinner you’d planned is the last thing on earth you want to eat.

If your weight-loss plan only works when life behaves itself, it’s probably not a particularly useful plan. I think flexibility is much more valuable.

Instead of asking whether you’ve followed your plan perfectly, look at what you do most of the time. One takeaway doesn’t make you unhealthy any more than one healthy dinner makes you healthy. The boring middle ground matters far more than either extreme.

Your environment matters more than we like to admit

Weight loss is often presented as though it happens entirely inside your head.

Make better choices. Have more discipline. Want it enough. But our surroundings influence those choices enormously.

What food is available at home? How much money do you have? Do you work shifts? Are you caring for someone? Do you have time to cook? Can you afford a gym? Are you dealing with stress? Do you sleep properly? Are you taking medicines that affect appetite or weight?

Two people following exactly the same weight-loss advice can have completely different levels of difficulty.

That doesn’t mean change is impossible. It means generic advice like “just meal prep every Sunday” isn’t equally useful to everyone.

The best weight-loss plan is the one that fits into your actual life, not the imaginary organised version of your life where you always have three hours free on Sunday afternoon and never get tired.

Weight loss doesn’t happen in isolation from your mental health

I also think we need to talk much more openly about what dieting can do to your relationship with yourself.

Losing weight can feel exciting, especially when other people start noticing. Compliments increase, clothes fit differently, and you may receive attention you weren’t used to getting.

That can make becoming smaller feel incredibly rewarding. The danger is when your self-worth starts shrinking and growing with your body.

If you regain some weight, suddenly it doesn’t just feel like your body has changed. It can feel as though you’ve failed as a person.

I’ve had to unpick a lot of that thinking. My weight is something about me. It isn’t everything about me. And I absolutely refuse now to spend years waiting to reach a particular size before deciding I’m allowed to enjoy my life.

Why I Refuse to Wait Until I’m Thin to Enjoy Life

Reaching target doesn’t magically solve everything

This is probably the bit I understood least when I was actively losing weight.

The goal was reaching target. Everything was focused on that number. What happens afterwards sounds easy, doesn’t it? You simply stop losing weight and maintain.

Except your body doesn’t suddenly hand you an instruction manual saying: “Congratulations! Here is exactly how to eat for the next 40 years.” You have to work out what maintenance actually looks like.

How much can you eat? How often do you weigh yourself? What happens when your weight goes up a little? How much fluctuation is okay? Do you still follow the same rules? What happens on holidays? At Christmas? During stressful periods?

And perhaps most importantly, how do you stop actively dieting without returning to exactly the habits you had before? I don’t think we talk enough about that transition.

There is so much information about losing weight and comparatively little about learning how to live afterwards.

Regaining weight taught me things losing it never could

Regaining weight isn’t something I would have chosen.

At the time, it felt incredibly embarrassing because I had been so public about my weight loss. I’d written about it, shared photographs and built a huge part of my identity around being someone who had successfully lost 10 stone.

Then I wasn’t that person anymore. Or at least, that’s how it felt. For a while, it was very easy to view the regain as evidence that I’d failed. Now I see it differently.

It taught me that weight maintenance deserves just as much attention as weight loss. It taught me that reaching a number doesn’t automatically fix your relationship with food, body image or the scales.

It also made me question some of the things I had previously celebrated. Was eating as little as possible really success? Was obsessing over weigh-in day healthy simply because the number was getting smaller? Was being frightened of regaining a pound a good way to spend the rest of my life?

Those are questions I didn’t ask while everything appeared to be “working”.

Does that mean there’s no point losing weight?

No.

I sometimes think criticism of dieting swings too far in the opposite direction and ends up suggesting that intentional weight loss is completely pointless because some people regain it.

I don’t agree with that either.

People have different reasons for wanting to lose weight. Health, mobility, comfort, fertility, preparing for surgery, reducing symptoms or simply wanting to feel different in their body can all play a part.

I don’t think it’s my job to tell somebody whether they should or shouldn’t want to lose weight. What I do think is that we deserve better than being told the solution is simply to try harder.

If you’re going to lose weight, I think it’s worth considering how you’ll live at the other end, rather than focusing exclusively on how quickly you can get there.

What would I do differently if I were starting again?

I wouldn’t try to be perfect. That’s probably the biggest change.

I’d choose something flexible enough to include meals out, holidays and foods I genuinely enjoy. I’d make meals filling instead of constantly trying to make them contain as few calories as possible.

I’d pay much more attention to protein and fibre because feeling satisfied makes everything easier. I’d also think about maintenance from the beginning rather than treating it as something Future Jen could worry about when she got there.

Most importantly, I’d try not to make weight loss my entire personality. I’d still go on holiday. I’d buy clothes I liked at the size I was. I’d be in photographs.

I’d exercise because movement could make me fitter and stronger, rather than seeing every workout primarily as calories burned.

I’d celebrate changes that had nothing to do with the scales.

And I certainly wouldn’t believe that my life would begin properly once I’d finally become thin enough.

Sustainable weight loss is probably less exciting

I don’t think the answer to why diets fail is one magic macronutrient, one perfect calorie target or a secret habit successful people know about. It’s probably considerably less exciting.

A sustainable approach needs to be something you can keep returning to when life inevitably gets messy. It needs enough flexibility that one meal doesn’t become one bad week, and enough food that you’re not permanently battling hunger.

It means understanding that your weight will fluctuate and accepting that progress won’t always happen as quickly as you’d like. It means building habits that don’t depend entirely on motivation.

And if you want to maintain the weight you’ve lost, it means recognising that reaching your target isn’t the end of the process. That’s perhaps the hardest lesson I’ve learned.

I didn’t fail because I regained weight

For a long time, I would probably have struggled to write that sentence.

I lost 10 stone and I regained weight. Both things are true. But the second doesn’t erase the first, and neither tells you everything about me.

My experiences have changed the way I think about dieting enormously. I’m much less interested now in whether somebody can follow a perfect plan for 12 weeks and much more interested in whether they’re creating something they can actually live with.

If you’re currently losing weight, I don’t want you to read this and assume I’m telling you you’ll inevitably regain it. I’m not. I want you to think beyond reaching your target.

Are you eating in a way you could realistically continue? Are you learning habits that will still make sense when there isn’t another weigh-in goal ahead? Are you enjoying your life now, or have you put everything on hold until you’re thinner?

And if you’ve already lost weight and regained some or all of it, starting again doesn’t have to mean repeating exactly what you did last time.

You know more now; I certainly do.

Losing 10 stone taught me how determined I could be. Regaining weight taught me that determination alone isn’t enough. And strangely, I think the second lesson might ultimately prove more useful than the first.

Useful next reads

If you want to read a bit more to help you then these posts I have written may help.

Why Does My Weight Fluctuate From Day to Day?
Perfect for anyone who struggles emotionally with individual weigh-ins.

Why Am I Always Hungry?
For readers whose weight-loss plan feels like a permanent battle with hunger.

How to Stay Consistent With Weight Loss
The practical next step after understanding why motivation alone isn’t enough.

Why I Refuse to Wait Until I’m Thin to Enjoy Life
The natural companion to the body-image/living-your-life section.

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