Review: This is Why You’re Fat

By Mike Howard

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Author Jackie Warner is a fitness trainer, very successful entrepreneur, and host of the Bravo reality series, Work Out. Her newly-released book: This is Why You’re Fat (and How to Get Thin Forever) promises you can “Eat more, cheat more and lose more – AND keep the weight off”.

Let’s have a closer look.Warner is an inspiring example of someone who struggled early in life, only to turn things around through healthy living. The premise of this book is essentially that hormonal imbalances are making you fat, and correcting them is the key to weight loss.

Hormones and Diet

  • According to Warner, it’s a matter of enhancing HGH, testosterone and progesterone, whilst squelching insulin, estrogen and leptin – these are the keys to keeping thin. And, she gives dietary and lifestyle tips on how to optimize these hormones.
  • Warner is very adamant that sugar is the prime driver of obesity and poor health in general.
  • The dietary plan involves a two week jump start program, which includes a daily dose of 2 eggs, 1 cup of oatmeal, 2-3 cups of veggies, 2 servings of fruit, a protein shake and herbal teas. Low calorie to be sure, but not terribly stringent.
  • The rest of the plan follows what Jackie calls a “5+2 plan”, which entails eating clean, healthy foods for 5 days, and enjoying 2 treat meals on the weekends. Essentially, the recommendations call for 4-4 oz. servings of protein, high fiber carbs, vegetables, fruits, fats high in omega-3’s and monounsaturated fats.
  • For fluid needs, 3L of water per day.


  • The exercise section has explanations on the different components of exercise, and why each is important.
  • Warmer recommends 20 minute high-intensity intervals.
  • There is also a section on strength training, as well as an illustrated workout program.
  • She also recommends a circuit-style workout to enhance fat-burning.

The Good

  • The eating plan is sensible, not overly restrictive, and low enough in calories and high enough in protein to be sustainable.
  • The plan is simple to follow and well laid out in terms of how to execute.
  • Warner advocates food journaling, and has a very good section on mindset and attitude.
  • There is a helpful section on how to read labels, grocery shopping and eating out.
  • Easy-to-follow meal plans and recipes.

The Not-So-Good

  • My biggest beef with the book was the amount of sweeping generalizations and spurious claims. While I understand that it’s common diet book strategy to use power words and make bold proclamations, Warner makes some misleading, partially true, but often false, claims throughout the book.
  • While keeping things simple is a good thing, oversimplification isn’t. As an example, hormones do have a role in weight regulation, however it isn’t as simple as eating X food and a switch goes on (or off) in the endocrine system.
  • Warner also tends to push the toxin theory beyond the realms of evidence-based research, and bandies about the term far too frequently for my liking.
  • She also falls victim to the common misconception that a pound of muscle burns 50-100 extra calories. This is WAY off.
  • I personally wouldn’t include jump lunges in a program designed for the overweight.

Overall Impression

Within this book you will find some sound dietary advice and guidelines with clear-cut outlines on how to implement it. The picture of Jackie Warner on the cover may even be sufficient motivation for many as she is someone who clearly practices what she preaches.

To summarize: her dietary advice is for the most part sound and simple enough to follow, but her rationalization for such advice lacks scientific support.


  1. Mars

    Jackie Warner can be quite harsh to beginners. I have tried her workouts and found some of them are hard to follow. Recently she has released a new workout DVD on how to shed off weight in 30 days.

  2. Mike Howard

    Sorry for the late reply : )

    Again credit to James Krieger for this, but it seems studies that cite a ~20cal/lbs metabolic boost are prone to error as they measure resting energy expenditure within 24-48 hours after the last weight training session. Therefore any residual effects of the last session on metabolic rate would make their way into the numbers (as protein synthesis from the last training session can still remain elevated at 48 hours).

    Hope that makes sense.

  3. Mike Howard

    From that paper…

    “The only relevant human controlled intervention trial with hard end-points that we are aware of found a non-significant (p = 0.10) increase of cardiovascular mortality in CHD patients who were advised to eat more whole-grain cereals compared to those who were not advised to eat more whole-grain cereals”.

    Again, we can’t look at extremes to make these comparisons – you claimed that there is a causal relationship between oatmeal (and other grains/legumes) and leptin resistance. This is what I would like to see evidence of. And if there is an affect – what does this RESULT in?

    Until then, your claims are speculative.

  4. Mike Howard

    I’ll have a more detailed look when I have time, but upon a cursory glance, the authors conclusions were centered around making current “agrarian” diets more healthy – not doing away with them completely.

    The study on leptin resistance was in pigs.

  5. b

    Hm. This makes me wonder if it’s a linear relationship or not. It’s possible that it either decelerates/levels off as you get more muscle, or that it accelerates. Do you know whether the studies that got closer to 20 cal/lb had the same size (30-40lbs) difference between their two groups?

  6. Ryan

    Really, any grain or legume. Traditional food preparation methods (sprouting, sourdough fermentation) seem to have an effect on lectins, which block receptors for leptin, but industrialization has pretty much killed those methods off.

  7. Mike Howard

    Any poultry, beef or fish should work (provided you aren’t a vegetarian). Nuts, peanut butter, cheese, greek yogurt, cottage cheese also work. Ditto with beans and legumes – although they lack all amino acids hence making them “incomplete”.

  8. Mike Howard

    Hi Ryan,

    Do you have evidence for this claim? Dose response?

  9. Mike Howard

    Most studies show about a 6-20 cal/lb. Segal et. al. showed closer to about 6. In his study, the metabolic rates of obese men were compared to muscular men of a similar BMI. The muscular men had resting metabolic rates approximately 250 calories more per day than the obese men and were carrying almost 39 more pounds of lean mass. This works out to about 6.4 cal/lb.

    Hat tip to my friend and colleague James Krieger for the above calculation.

  10. Mike Howard

    I concur, spectra. I always get a good chuckle when people refer to sugar as “poison”. Her bit on sugar is a little over-the-top and alarmist. I’ll get into some of the other issues of the book if time permits.

  11. laurenthompson

    “The dietary plan involves a two week jump start program, which includes a daily dose of 2 eggs, 1 cup of oatmeal, 2-3 cups of veggies, 2 servings of fruit, a protein shake and herbal teas. Low calorie to be sure, but not terribly stringent.
    Im allergic to eggs”

    —-But Im allergic to eggs. Is there anything I can substitute it?

  12. Ryan

    But oatmeal creates leptin resistance…

  13. Ashley S

    So how much DOES one pound of muscle burn?

  14. Spectra

    I’ve heard different reviews about this book and I think she’s a LITTLE too harsh on sugar. She acts like it’s pure poison, etc. I happen to think that there is room for a little sugar in an otherwise clean diet, as long as you count the calories in it. I’d like to read the book to see just exactly what kind of claims she makes regarding hormones.

  15. Mike Howard

    You are most welcome : )

    To be fair, I think Jackie’s advice is generally good – I just found a boatload of erroneous and misleading information in both the nutritional and exercise sections.

  16. M.C.

    Thanks for the review, Mike. I’m pleased that she brought up the endocrine system at all, but you’re right that it doesn’t help if she’s giviing misleading advice regarding how to manage it.