Fat Smash Diet

fat-smash-dietThe Fat Smash Diet is found in the book of the same name, which is written by Ian K. Smith, M.D.

The principle behind the name is that you achieve your weight-loss goals by smashing bad habits and misconceptions about diet.

The diet follows a 90 day program in 4 phases – detox, foundation, construction, and the temple.

The Fat Smash Diet is also used by popular TV show Celebrity Fit Club.

Fat Smash Diet Program

The Fat Smash Diet lays out your plan over 90 days for developing healthy eating habits and a healthy lifestyle, to promote fat loss and maintain a healthy weight.

Phase 1 – Detox (9 days)

Diet is essentially vegetarian – mainly fruits and vegetables (raw or steamed/grilled) to absorb natural nutrients, vitamins and minerals in 4 or 5 small daily portions, 3 hours apart, with plenty of water – plus daily exercise (30 minutes cardiovascular exercise 5 days a week, or a walk after dinner for up to 25 minutes).

This phase rids the body of toxins and impurities, developing a good basis for the following phases.

Phase 2 – Foundation (3 weeks)

Additional foods are allowed from a given list (lean meat/seafood, selected cereals and extra dairy), and physical activity is increased by up to 15%. The eating regimen of phase 1 is maintained (strictly no meals to be skipped) including plenty of fruit and vegetables, and fried foods are a ‘no-no’.

This phase establishes good eating and exercise habits for a healthy ongoing lifestyle.

Phase 3 – Construction (4 weeks)

Yet more additional foods are allowed from a given list (such as pasta and bread), portion sizes may be increased maintaining plenty of fruit and vegetables as before, with at least 4 daily meals stipulated.

1 non-fruit dessert per day is permitted (1 scoop low fat ice cream or 2-3 cookies or graham crackers) and physical activity is again increased by up to 25%.

This phase builds the diet plan up from the earlier ‘toning-down’ phases.

Phase 4 – The Temple (remainder of the 90 days)

Most foods previously denied may now be included in limited quantities, and physical activity set at 1 hour for each of 5 days weekly.

This phase is to maintain the ‘temple’ of your body, in which your lifestyle achieves a balance for maintaining your desired body weight. If your goal weight has not been reached by the end of the 90 days, phase 1 may be repeated.

Look  for healthy meal ideas here.

Fat Smash Diet Book

The Fat Smash Diet book by Dr. Ian K. Smith M.D. contains the program philosophy and details of each of the 4 phases of the program, plus 83 pages of recipes and menu ideas. The book has four appendices of useful information:

  • A body mass index chart for setting your weight goal.
  • The fiber content of common foods for increasing your dietary fiber intake.
  • Food nutrition label information.
  • Calorie expenditure charts for common exercise/physical activity programs.

Available from Amazon →


The Fat Smash Diet program has a growing following, especially given the exposure through Dr. Smith’s involvement with the VH1 Celebrity Fit Club. Many testimonials are positive about the results achieved, and the relative simplicity of the approach to weight loss as set out in the Fat Smash Diet.

This is a simple diet program, manageable and by all accounts helpful.

See Ian’s newest diet: Shred: The Revolutionary Diet, which combines the best of this plan and his other books.

  • Smith, I. K. (2012). The Fat Smash Diet: The Last Diet You’ll Ever Need. Random House.
  • Rolls, B. J., Ello-Martin, J. A., & Tohill, B. C. (2004). What can intervention studies tell us about the relationship between fruit and vegetable consumption and weight management?. Nutrition reviews, 62(1), 1-17. study link
  • Taveras, E. M., Berkey, C. S., Rifas-Shiman, S. L., Ludwig, D. S., Rockett, H. R., Field, A. E., … & Gillman, M. W. (2005). Association of consumption of fried food away from home with body mass index and diet quality in older children and adolescents. Pediatrics, 116(4), e518-e524. study link
  •  By Mizpah Matus B.Hlth.Sc(Hons)

    25 Comments or Reviews

    Comments now closed
    1. Cinthia

      I got the book today i finished reading it. The book is very short; clear and easy to follow. I will start tomorrow.

    2. shar


    3. Jenna

      I am starting this diet Saturday, (I’m going to buy the book and groceries tomorrow) I’m glad I found this website, its encouraging! I hope to lose about 30 pounds. I have to stay strong!

    4. Nosha

      I am on day 7 of phase I and hope to lose up to 30lbs. It is very difficult as I am married to a personal trainer who looks great and eats whatever he wants without weight gain. I am going to day it, but I must admit I can’t wait till Wed. as then I can weigh in and eat meat!

    5. Sonja

      I am hanging on phase 1 my family had mother’s day dinner of steaks, shrimps, baked potatoes,salad and others such cake and pies. I am so proud of myself because i’m at day four and just ate veggie and water that was temp. But got through it.

    6. Sonja

      I’m on day three of phase 1 it is hard but i am hang on.

    7. Borum

      Diet is essentially vegetarian – mainly fruits and vegetables (raw or steamed/grilled) to absorb natural nutrients, vitamins and minerals in 4 or 5 small daily portions, 3 hours apart, with plenty of water – plus daily exercise

    8. Borum

      Hi Mickey,
      I’m about to start this diet on Monday. But what I’ve read so far, Veggie Burgers are not the same as Vegatable,Fruit. Please keep in mine the 9 days is for DETOX. Stay encouraged, I will be here to support an push you..

    9. mickey

      I’m on day 6 in phase I and so far so good. I feel lighter, lets see how much I lost on day 9. Question, are veggie burgers ok in phase I? I bought the morning star and love them..

    10. ESV

      Well I really wanna start this diet, I’ve heard a lot of good things about it and I am so ready to lose weight. I need to lose about 135 lbs. I am 5’4″ and weigh damn near 280 lbs. I have Poly Cystic Ovary Syndrome (PCOS) and was told that it is the a big reason for my weight gain. But I must admit that I don’t always eat the most healthy foods. I have cut out sodas and all other caffeine so hopefully that and the fat smash diet will help. If there are any other ladies out there with PCOS please let me know of any other diets that may help me. Good Luck and happy dieting to all of you.

    11. Lisa

      Oh, BTW – there is a support group that gives you helpful hints and menus for each phase of this diet:

    12. Lisa

      I am a 44 yr old mom of 3. A year ago I graduated from Nursing school and found I had gained 67 lbs over the last 5 yrs of school. I had been trying to lose weight by working out and cutting back on snacks. I didn’t think I ate much but I ate mostly at night. My mother told me about this diet and I started it January 5th 2010. As of today, January 28, 2010 I have lost 17 lbs. You are supposed to exercise every day, but I really have only had time to do it 3 times the whole month. I am very happy – this diet WORKS!!

    13. linda crumm

      What about popcorn, is that allowed in phase II?

    14. linda crumm

      anyone currently on this diet?

    15. Naomi Wright

      LOL! People who are larger will lose more weight then folks that are smaller so it’s possible that she did lose 125 lbs in 3 months. Highly likely but possible and it depends on what she ate and how much she exercised.

    16. Tanisha McCray

      I have a question. In Phase 2 can you have Banana Nut cereal?

    17. Tamara

      It works!
      Lost 18lbs after 3 weeks, 165lbs- 147lbs and I’m still on it.

      Even with a busy schedule- focus and determination will get you there.

    18. Meka

      I just started doing the diet …first exercising for the first week then starting the detox next week to make sure I can exercise 5 days a week so I won’t give up..

    19. Cammi

      How in hells bells did you lose 125lbs in three months?!! My goodness! You must have been doing some HARD CORE EXERCISE!…like 5 hours a day or something!

    20. Susie

      Congrats to everyone on there weightloss… I just started my first detox day today, it’s alright, pretty tough. I hope to lose about 60lbs. This hopefully is perfect since my problem is portion sizes and what to eat….

    21. lesha

      Yes this works. I exercise as well doing for helps you lose the weight it’s not a diet it’s just agood way to live by eating healthy and working out


      i have tried this diet. DETOX is hard but its worth it. i dont think it should be called a diet, its more of a lifestyle change. i have 2 say congrats to losing 125lbs but in 3 months? how did u do it?

    23. Obaid Hashmi

      Are you sure you lost 125 lbs in 3 months ??
      I mean thats terrific..
      What exercises did you do?
      And was it difficult ?

    24. Sarah Reidy

      Oh yeah, it was so great.. i used to weigh 250 pounds but now im down to a healthy 125. GO FAT SMASH!!!

    25. question

      Does it work