What To Do If You Mess Up Your Diet


It’s a situation familiar to many a hardened dieter. You’ve had a “bad day”. Maybe it was that unplanned cookie mid-morning, that bag of chips you shared with a colleague at lunch time, or that mid-afternoon candy bar … whatever it was, you feel like you’ve “failed”. You’ve broken your diet, and you might as well give up.

This line of thinking is why many of us are constantly on and off diets, yo-yo-ing up and down and feeling increasingly frustrated with our eating patterns, and with ourselves.

It doesn’t need to be that way, though – you can stop a dieting slip-up from becoming a dieting disaster. Here’s what you need to remind yourself (write these out and stick them to your fridge, if necessary):

  • One cookie won’t ruin your day
  • One skipped gym class won’t ruin your week
  • One day won’t ruin your diet

One Cookie Won’t Ruin Your Day

I call this the “one cookie” principle, but it applies to all sorts of other foods – so substitute your own weakness (bar of chocolate, slice of cake, etc.) where I’ve put “cookie”!

A single cookie has around 80 – 120 calories. One of those isn’t going to ruin your day. It takes 3,500 calories to gain a pound. That’s about 30 – 40 cookies, give or take a few. If you eat an unplanned cookie, give yourself permission to shrug it off. It’s a cookie; big deal.

What you must not do is give yourself permission to write off the whole day. “That’s it, I ate a cookie, I might as well give up.” Come on – can you imagine doing this in any other area of life? “That’s it, I overslept by 15 minutes, I might as well not go to work at all now.” Of course not … when you have a minor slip-up, you just get on with things as best as you can. That’s exactly how it should be with your diet.

One Skipped Gym Class Won’t Ruin Your Week

Maybe you’re okay when it comes to recovering from food-related mishaps. Perhaps your problem is exercise. It goes something like this: you end up working late on Monday, and missing your step aerobics class. And since you’ve now “failed” at your self-imposed exercise regime, you may as well not go to the gym at all this week…

Again, this is a silly way to think. You’re unlikely to see any dramatic loss of fitness based on skipping a single workout. Why not go for a late-evening jog or walk, so that you still get some exercise? Or try out the Tuesday class instead?

Don’t get hung up on being perfect. Again, in other areas of your life, you wouldn’t think in such “all or nothing” terms: if you missed a small project deadline on Monday, you wouldn’t give up hitting all your deadlines for the rest of the week.

One Day Won’t Ruin Your Diet

Here’s the biggie, the one that trips up most dieters. It’s the day from hell. It’s the day where you ate a cookie for breakfast, a chocolate bar mid-morning, and gave up completely by lunchtime. You scoffed a double-cheeseburger ready-meal for lunch, and numbed your feelings of guilt and failure with chocolate all afternoon. Now it’s evening, you’ve just polished off a pizza and a tub of ice-cream, and you’re giving up on your diet for good.

That’s your big mistake. Not eating the cookie, or the chocolate, or the ice-cream … but giving up. One day, however badly it goes, won’t be at all significant if you stick (more or less) to your diet for the next few weeks. Draw a mental line under the day (or a real line in your diary, if it helps), and start afresh.

Once you’ve realized that one cookie doesn’t ruin your day, though, you’re much less likely to have these day-long disasters. You might occasionally eat something you’d not planned, but you’ll shrug it off; maybe you’ll have a bit less lunch or dinner, or you’ll do an extra ten minutes in the gym, to get yourself back on track.

How do you stop your diet slip-ups from becoming diet disasters? Let us know in the comments…


  1. Monique 1 month ago

    I know I have to go back on the diet, but slip ups hurt, even though the cheat felt good at first

  2. Jin Kim 1 month ago

    It’s really hard to keep up with my diet. I ate 3 whole bags of chips yesterday, today I ate lunch (I do intermittent fasting with a normal diet plan.) I was sad. I just thought about my diet and workout but did nothing that day. I didn’t exercise or even consider it. Today, as I am writing this, I feel guilty that I ate this food. I hate myself, and I cannot motivate myself to workout. Help me and please email me.

    • Carolina 3 weeks ago

      Just keep going do not feel unmotivated please.. every day is a new day!

  3. Ash G. 5 months ago

    I had 200-300 cals worth of sour cream and onion chips. I feel so so so guilty.
    lost a little under 4 lb this week. I was doing so well :(. Today was really stressful tbh. I’m about to go to the gym in a bit. I burn around 300 cals in 30 min on the eliptical. I usually do an hour work out i should be okay.but i’m still sooo mad at myself. Im sure the drop tomorrow wont be as much because of the chips’ fat and sodium content

  4. Kelsie Stahl 11 months ago

    I’ve lost 12 pounds and this past month I’ve ruined my diet so bad and gained some weight back. I feel like a failure. I really want to restart but I feel why bother I’m just going to mess it up again. I have no will power, I’m so weak and I hate myself for it. I struggle working out I never get used to it I constantly had to push myself when I was working out. I feel like I can’t do it without help, but I also don’t have anyone to help me. 🙁

    • Ted 11 months ago

      Perhaps your dieting is too strict or restrictive?

    • Kateri 3 months ago

      Hey Kelsie!
      Stop being so hard on yourself! The first thing is that you have to do this from a place of self love. The fact that you lost 12 pounds is a HUGE deal! Also too though, losing 1-2 pounds a week is the healthy way to go so make sure youre not being too restrictive, because if youre not eating enough calories youre starving yourself and messing up your metabolism. Losing 12 pounds does not sound like no willpower to me!

  5. Julie

    I’ve beeneating in a clean and healthy way, but this week has been so hard for me to stick to it though. I’ve been eating more than one cookie the last three days and telling myself I’ll get back tomorrow, tomorrow hasn’t show up yet though. And I’m feeling so sad like I’m a failure, I’m scared I’ll gain back the weight I’ve lost already.

    • Good luck 1 month ago

      Best time to start is today. Challenge yourself. Be kind to yourself. Trick yourself. Teach Yourself. Do anything it takes to break the ice and get back on the horse. You can do it, others have done it. Youve done it before. Nothing is stopping you.

  6. Nae

    Anddddd, I’m going out to dinner this Friday and plan on eating hot wings and fries!

  7. Nae

    I totally ate a brownie and I’m am on my fourth week eating healthy and working out . I haven’t cheated on my meals at all and I have a nutritionist and only missed two days in the four weeks. I also didn’t work out today. I just feel so terrible, I am really aiming to get this weight off me. Did I ruin it all 😩

    • Ted

      Hi Nae, You should look into flexible dieting. It allows you to have treats like brownies without messing up your diet. It’s truly life changing for some people, especially those that obsess about certain foods: https://healthyeater.com/flexible-dieting

  8. Em

    The worst thing is when you eat something you thought was healthy only to find out it had something like corn syrup or sugar in it! 😬 that’s what I get for not reading ingredients though. I’m not giving up!

  9. Lisa

    I feel somewhat better, but I had more than one cookie.

  10. Erica

    I just ate the whole bag of cookies and half a pizza, i feeel like i ruined my diet i may as well not workout today. What should i so i need help???

    • Ted

      Get back on the wagon tomorrow.

    • Lisa

      Go work out! I ate more cookies than I have ever eaten today so I am not going to ruin the whole day. I am going to the gym.

    • Ofri 4 months ago

      What is the logic in “I may as well not workout today?”
      Today you need it more than on “good” days, since you’re in a caloric surplus. This is precisely the defeatist mentality this article is about.

  11. Karen

    I just ate two handfuls of fritos from my sons bag.. I feel horrible i had a heavy led day yesterday and i am so sore. I suffer from a heel spur so i know when to rest I’m just so pissed that I was tempted to eat chips when i never eat them.Other then that i had a great feeding day. Sucks when others eat what they want. I describe my body as a gainer i gain muscle but i also can easily gain fat so i have to be disciplined especially as i am trying to reduce body fat and reduce my tree trunks

  12. Lauren

    I’ve just started becoming more self concious and I cycle a few hours a day as I suffer from anievty in the Gym and I have tried to wean myself off the junk but it is hard, I limit what I eat and make sure I stay under 1,500 calories a day but today I have been feeling so bad and I had a chocolate bar this morning, then AFTER my cycle I ate a bag of pick and mix sweets and then Belvita cookies which are like 4 in a pack. I feel so bad but reading this makes me feel slightly better but it’s hard especially after I ate a good breakfast and good dinner!

  13. bobby

    It actually could mess up your day. Sending signals to your brain thinking that you look gross or you feel fat etc. Also depending on what you eat and at what time can have serious effects. Like eating a pizza and a tub of ice cream at night. Well guess what your gonna sleep on that pizza and ice cream and it will turn to fat. Just like magic!! If your gonna diet, do it right and don’t half as’s anything. My 2 cents.

    • Matt

      Except no. Studies have shown repeatedly that “meal timing”, yes eating at night or before bed, does not result in the food bring converted to fat. Please get your facts straight before advising others. You could do a lot more harm than good.

      • Ewan AD Roy

        Well said, Mark!

        • Damiam 1 week ago

          Who the hell is mark lol

  14. Rose

    Hi, So every fortnight I meet with my friend and 2 weeks ago we had two small slices of cake and yesterday we had greasy fish and chips and another slice of cake. The cake seems to be a regular social thing we have when we meet and my diet has gone completely off the rails now. What shall I do?

  15. Brittany

    I’ve been dieting for about a week now and this morning i ate two burritos and that’s 625 calories I really feel like I’ve messed up . It’s really hard dieting when all my family does is eat unhealthy for in my face . I have been craving sweets but I don’t give in something made me give In this morning.

    • Ted

      Just reduce your calories the rest of the day. You really should check out flexible dieting which is a much more relaxed approach and allows you to eat burritos and some sweets. https://healthyeater.com/ebook

  16. Cindy

    For me, I like to have a healthy and high calorie breakfast that keeps me full and focused in the day, then unprocessed food like sandwiches for lunch, the trick is eat less for dinner, such as a salad, some vegetables with chicken breast, apples and grapes. This way I have a good balance of fruits, protein, grains, diary and vegetables every day. Then pair with some treadmill running sessions three or four times a week and I’ll be in shape and feeling fit. I do have those ‘bad days’ but I realize it’s part of the process of being fit and losing weight…if you accept it, it will be so much easier! Then you would be motivated and determined the next day, instead of giving all up. Plus, I find myself wanting to eat fresh and clean foods the next day, if I ate greasy and spicy and sweet foods too much on my ‘bad day’, I also crave less. It’s like my taste buds changed.

  17. Sally

    I have been eating healthy, drinking lots of water and going to the gym for 36 days now! I have cut out wine and chocolate my two favourite things ?

    Only yesterday I slipped up as my other half ordered an Indian..and also some chocolate (well quite allot) i have noticed such a difference in all my hard work.. my stomach has completely bloated back out and feel flubby all over again (may be in my head) but deffo feel it.

    I now feel very unmotivated and now have the taste for sugar! Will try get back on track tomorrow but very very hard with Valentines Day and Easter coming up ?

  18. Kelli

    Next weekend is Valentine’s Day and my family has a pizza and big heart shaped chocolate chip cookie tradition and i love chocolate chip cookies, i know imma want to pig out. Will eating pizza and a lot of cookie erase all my progress (i’m not overweight exactly just tryna lose a few pounds, only started a few days ago)

    • Ted

      It’s all about the calories you can and do consume during each day. Figure out how many your body needs for weight loss and/or maintenance and stay close to that amount. You could try to save the majority of your calories for the “pig out” and also exercise that day, which will allow you to eat even more. https://www.diet-blog.com/05/how_to_calculate_your_daily_calorie_needs.php

  19. Tim hutton

    Hahaha if it makes anybody feel better. I had two hard workouts today. One in the morning and one tonight. Haha I cheated last night and had a huge thing of pasta. Hahaha then tonight I was starveing I searched the cabinets and found a whole drawer full of candy. Is this common for women by the way a hidden drawer of hoarded candy. Anywase I just ate a little bag of sour candies mmm they where good. Sooo tommorow is going to be another super early day. Keep at it people think happy thoughts and don’t let it eat you up.

  20. Dean

    I have been on a diet now for 2. 1/2 weeks! Also I am working out very instenstly everyday except Sunday! Well today I have for medium size peices of fried chicken, I just want to beat myself up! I know I might not even put on weight or a a pound at most! But it sucks to take 2 steps back and 1 step foward I was 190 and today’s weight was 178.5

    • Mallory Parlier

      What have you been doing for your diet? I can’t seem to lose any weight at all and you’ve lost over 20 pounds in 2 1/2 weeks!

      • john

        11.5 lbs

      • Damian 1 week ago

        If you buy a treadmill (craigslist) and push out 20min with a 4.5 incline at 4 to 5 mph and slide up to 30 min the following week everyday your get a big boost in weight loss, if your not the runnong type that is. Heavy. I was 252 im now 236 in 3 weeks this is what i have been doing and i just joined jiujitsu.

  21. Mar'Taja

    I felt so bad. I have been dieting to get into tha Army. I weight 169lbs. My goal is 165lbs. I messed up today. My recruiter put me on a green vegetable and water diet. It made me sick so one day last week I ate a few sour patch kid candies. Yesturday I ate more cereal than I should. The same with today. I was at 38% bodyfat. He gave me until April 8 to get to 32% body fat. 6% I haven’t stopped the workouts though. Will those things ruin it for me even if I get right bsck on track tomorrow and stay on track until Monday? My meadurments taken March 28 2013 was 180lbs 40D-32-45.
    My goal is 165lbs 40D-30-42.
    The recruiter said I could do it IF I stuck with the diet. But I slipped 3 times. To keep from getting sick I eat Saltines and lemon and low-valorie flavored water. Can I still make it by Monday IF I stick to it for the next 5 days?

    • Marv

      Yes you can. If you believe you can then you will. You just need to want this like you need to breathe fresh aircevery second. Try dipping youre head under water for 2 minutes and then tell yourself yoi want this like you want that goal. Then dont bust youre mind just bust the gym or tge street with some mean workout and stivk to the diet. Every action has a reaction. You must act in order to get get a rwaction from life. Just remember you cannot climb the ladder of success with youre hands inside you’re pockets. You gotta work like hell and smash your goal.

  22. Rose

    I had more like a two day slip up and felt totally crap after pigging out i felt like a failure and really down but after reading this article and I feel much better and have told my self that tommorow shall be a new fresh day and hope fully by summer i will have dropped a dress size

  23. catey

    This is what I needed to read. Had a piece of black forest cake today. Tasted good, but ever since I’ve felt horrible. I need to stop putting so much pressure on myself. Tomorrow is a new day

  24. christine

    Can smoking mess you up when you doing your workout

    • Ted

      Really? Of course.. smoking messes up your entire body.

      • Jerry

        Not true I smoke a little after a workout and I make all kind of gains. The only thing that sucks about smoking is the munchies lol

        • Ewan AD Roy

          Are you talking tobacco or something else? If its the former there is absolutely nothing to gain from smoking tobacco! If its the latter then you will still damage your lungs but it can help some people with eating disorders and anxiety and things…

  25. julz

    thanks so much! sadly i just read this article AFTER i had a piece of banana bread, then had 3 more after that… but now i know for tomorrow that one slip up is a-okay! thanks!

  26. Patty

    I ate a bag of cheetos today and after reading this article, I don’t feel bad at all!! Now I’m back to being happy and satisfied from the cheetos! Thanks!

  27. Georgie

    I am so glad I read this! A colleague just gave me a piece of cake which I ate because I can’t resist it when its in front of me (NOT because it would be rude not to as I told myself ) and after eating it I started thinking to myself “right well I’ve ruined today so might as well go to the cake shop and buy 5 more” but then I read this article and all your comments and now I don’t feel like doing that at all. I’ll just have a salad for dinner and tomorrow is another day! Yay! Thank you! Diet disaster avoided!

  28. Myduh

    Oh my good this article makes so much sense, specially number 3! I added this to my favorites, I NEED TO REMEMBER THIS!
    ” It’s the day where you ate a cookie for breakfast, a chocolate bar mid-morning, and gave up completely by lunchtime. You scoffed a double-cheeseburger ready-meal for lunch, and numbed your feelings of guilt and failure with chocolate all afternoon. Now it’s evening, you’ve just polished off a pizza and a tub of ice-cream, and you’re giving up on your diet for good.” That, right there, is me.

  29. Jennie

    I have recently lost 6 stones by eating healthy and cuttin out crap but then last night I ate chocolate tart for pudding in a posh restaurant, I went to bed feeling sooo guilty and worried that I’d ruined my whole diet but readin this has helped me feel a little better and am goin to get back on track today 😀

  30. kittycatmeowww

    Wow your post made so much sense!
    I binged high time today and I was feeling so lousy till I came here.
    Everyone who really feel horrible after pigging out should seriously come here to calm themselves down.

    Thank you so much, it really made me feel so much better about myself (;

  31. Khulan

    you’re absolutely right. very liberating. thanks

  32. torie

    I have decided to make a lifestyle change and have been exercising and eating 1200 healthy vegetarian calories a day for last 2 weeks. Today I got home really late and was so over tired I ate pizza and a medium slice of pineapple cake. Now I’m laying in bed crying because I feel all my work has gone down the drain.

    • Tim hutton

      Oh no don’t feel like that you really just need to enjoy and savor the little things. Still gotta live life and enjoy it. It’s a life style change. Can’t eat Nuthing but rabbit food forever and you can’t expect to just jump head long and change a lifetime of eating habits in a couple weeks. It’s a long process that you practice and get better at over time.

  33. shay

    I think we ALL beat ourselves up when we mess up a day. But the TRUTH is tomorrow is another day, a fresh start and what you did today doesn’t matter its what you do tomorrow that counts. As long as you get back on track its NOT failure. i hate the word “DIET” its like setting you up to fail right from the start, because diets are short term, and mentally your waiting for the day when the diet ends. A Lifestyle change is better, but you have to ALLOW yourself treats and “slip-ups” from time to time. for it to work LONGTERM. I just take it DAY to DAY..one step at a time..Time is the constant, its going to pass no matter what..the thing we can change is what we do today.

    • JenineTryinToEatClean

      That was so nice… and so true. Personally, I think I have a hard time with “lifestyle change” for the very reason that I think im going to have to eat like this for the rest of my life – very restrictive and no dessert. Albeit I do feel amazing. I think my issue is addction to sugar. However I will start to approach this as a lifestyle change… and come to terms with there being no end in sight (maybe that’s still very negative). But a change that allows “treats”.

  34. The crazy one

    Im on Atkins with a twist . Im not about the fat and stick to 40 or under ! And I need to stay at 30 carbs a day that drives me crazy at times . So I messed up today and had yum jello pudding with heavy cream ! I feel like I messed up and my weeks are gone . But your so right about its just a slip and just keep at it . So for the next 4 days Im going hardcore and then I will treat myself to another slip up 🙂

  35. Charles

    I think it is important for people not to beat themselves up when they make mistakes. The great thing about eating healthy is that with each passing day you have another opportunity to do well.

    Keep stacking up those healthy days and before you know it, the healthy habits are easier than the unhealthy habits.

  36. Barbara Bartocci

    I repeat these words from the book, Grace on the Go: Quick Prayers for Determined Dieters:
    “Failure is not the same as quitting.
    Though I may have failed, I will not quit.
    Strengthen me, Lord, as I start again.” (And if you’re not into words like “God” or “Lord” just say
    “Give me strength as I start again.”

    • JenineTryinToEatClean

      Thank you Barbara! That was just what I needed to hear. I had a rough day at work today. I wanted to eat something sweet or fried. I didnt necessarily want to completely quit my diet… but I daydreamed about quitting my job. Your prayer helped me with both issues!

  37. Cenegenics Atlanta

    When a Slip Up becomes Disastrous I believe it reflects a basic lack of commitment to change. “Dieting” has to be a life style change you can live with long term, not a temporary fix that is prone to rebound and failure. You can recover from a Slip – just refocus and move on.

  38. sinamin

    I love this! I used to never eat dessert before because I always thought it was “bad” for me. I recently signed up with Freshology and they give me a dessert everyday! It really helps take the edge off and makes me feel like I’m not restricting myself.

  39. Edwin

    The main problem here is that people see Diets as something temporary when you should see it has a lifestyle change. It should be a way of living. The majority of the people gain back the weight because they think that once they lose the weight they can go back to there bad eating habits and that’s were they commit the big error.

  40. julie

    I shrug it all off. Sure, weight loss is slow, but it keeps happening, and I’m not driving myself insane. I made the mistake of “dieting” once before, and when I finished, I gained back 50 pounds, so now, if it’s not a way I can eat the rest of my life, I dont even bother to go there. One piece of cake or a cookie doesn’t make one fat, unless it’s the whole cake, or every day.

  41. Charlie Hills

    If you do let a few slip ups lead to a complete dietary face-plant, I read about a good trick on NPR last month: the twenty-four hour fast. It’s not a trick to lose weight, but a way to get your body back on track, by allowing your blood sugar and insulin levels to even out. It helps break that cycle where the very act of overeating is what causes you to overeat even more.

  42. Gregory Hayes

    Nice perspective. It’s always important to keep things in perspective. We’re all going to fall off the wagon sometimes. Don’t stress about it.

    Great insight.

  43. Cari from ditch diets

    In The Mind over Fatter Programme I talk about stopping a slip from becoming a dip from becoming a dive. It’s so easy to indulge in black and white thinking and to think we have to do everything absolutely perfectly. Then when we don’t we get what i call the ‘what the heck syndrome’… as in … what the heck, I’ve blown it, I might as well just keep eating today and I’ll start again tomorrow – that turns a slip into a dip. But when tomorrow comes and the ‘what the heck syndrome’ continues and keeps continuing after that even it becomes a dive.

  44. The Baroness

    This is the one thing that was the key to me losing the last of my weight. I would mess up and then think: “Well, I’ll start again Monday because I’ve messed up.” Of course, Monday would never come. When you start letting go of your mistakes, you can let go of your weight.

  45. Viveca

    Well I haven’t been that good lately – many slip ups. My biggest excuse is that I am not fat but the truth is I need to get into better shape – cholesterol is too high.

    Long time ago I read that it is too difficult to break a habit (like being lazy!) and that the best thing to do is form a new habit (like going to the gym a couple evenings a week.)

    So — that is my plan. That and a mantra like “I choose to live well.”

    Years ago I quit smoking with a mantra “I choose to breathe.”

    Great topic – thanks!


  46. FJ

    Yup… the problem is people keep thinking this way until they’ve eaten about 50 cookies.


    It’s why Lays Chips has one of the best slogans I’ve ever heard. “Betcha can’t eat just one”

    “just one”… that word is F***ing dangerous!

  47. Spectra

    Back when I used to “diet”, I had so many “That’s it, I ruined it” days. I would resolve to eat bran flakes with skim milk for breakfast, but after driving my siblings around on their 5 am paper route, I would decide to stop at Kwik Trip to get a donut and cappuccino for breakfast instead. And since I “ruined” breakfast, I figured I might as well just eat crap the rest of the day too. I think what made it different for me when I decided to make over my lifestyle was that I planned for the splurges I had. By planning them into my day, I didn’t feel so tempted to cheat.

    Although, I did have one “day from hell” that probably could easily have derailed me for at least a few months…I had made a pan of Rice Krispies treats with chocolate chips melted on top and planned to eat only one a day. However, I managed to eat half the pan over the course of the afternoon. I think I managed to survive that one by telling myself that it was just one day of bad eating and that I would just eat less the rest of the day and get right back on track tomorrow. The good thing that came out of that was that I never really liked Rice Krispies treats as much after that, lol.

  48. Vtrimmer

    If you are looking for help in modifying your relationship with food, you should check out Vtrim. Vtrim is an online, behavioral management weight loss program based on 18 years of research at the University of Vermont. If you are interested, you should look at the website: http://www.uvm.edu/vtrim

  49. Heather

    That’s it, I overslept by 15 minutes, I might as well not go to work at all now.”

    This made me laugh for some reason
    Excellent comparison

  50. FatGuyThin

    I try not to classify foods as “good” or “bad”. Food is food. A chocolate bar is not inherently “bad” the same as broccoli is not inherently “good”. They just vary in nutrient quality. Classifying food as good or bad can lead to feelings of guilt. And guilt is not an appropriate emotion to have after eating.

    I was speaking to a friend recently who told me she was on a diet. She said that she had been “good” all day and felt like she deserved a treat. It was as if she was about to commit a cardinal sin by having a cookie with her cup of tea. She felt guilty just thinking about it. That cannot be healthy.

    The other thing I like to remember is that one meal will not make you fat. It’s what you consistently choose to eat that makes a difference.

    • Ella

      Thank you for the advice. I’ve stuggled with weight issues for most of my adult life. I am curently at my goal weight and I’ve maintained a healthy life style for 3 years. I can be very hard on myself and occasionally I’ll binge on junkfood. The comments and thoughts I’ve found here today have made such a difference in my attitude towards myself. I feel relieved. Thanx again ?