I have to put aside my revulsion of everything Dr. Oz to write this review of the System 20 Diet, which Dr. Oz says isn’t a diet at all. 

Okay. I’m good.

Let’s do this.

What Is The Dr. Oz System 20 Plan?

System 20 is Dr. Oz’s weight loss and lifestyle plan for 2020, having launched this month for the new year. Oz claims that ‘dieting is dead,’ and we all need something healthy and non-diet to help us ‘take our health into our hands.’  Okay then!

The System 20 plan is made up of 20 ‘rules,’ which you can see on this infographic I got off of Oz’s site.

It sort of looks like the cover of Women’s World Daily Magazine, which incidentally is the usual vehicle for Oz’s crap:


Dr Oz System 20

Some of the rules are common sense. Sure, go to bed at the same time every night. Sleep hygiene is really important, I’ll agree with that. Do some meditation. Okay, fine.

But the nutrition part of System 20 – which is why we’re here – is pretty brutal. 

I can’t believe I have to say this AGAIN about Dr. Oz, because it has been said plenty of times, but for someone who is a DOCTOR and should be evidence-based, he really misses the mark here. Our society trusts medical professionals to be legitimate and honest. 

And if he was, he’d call System 20 a low carb intermittent fasting diet. Because that’s what it is, plus a couple of bullsh*t additions along the way. 

Let’s take a closer look at System 20

I think we should address the IF part right off the bat, because that’s a huge part of System 20. 

Intermittent fasting has some pretty solid research going for it, but it’s not for everyone, especially those with a history of eating disorders, pregnant women, or type-1 diabetics. 

Combining it with a very low carb diet like System 20 does, can be super-restrictive and tough to follow. And when something is restrictive and tough to follow, people can’t sustain it. Especially when it’s low in calories, but more on that later.

When you can’t sustain a diet, you go back to where you came from. Don’t worry though, I’m sure Oz will have another ‘miracle cure’ ready and waiting!

One of the reasons why Oz loves IF is that he claims that it improves longevity. But Instead of posting human research – because there is none for IF that looks specifically at lifespan, he posts this:

“(Intermittent fasting) started back in the 1930s when Cornell researcher Clive McKay found that rodents who consumed less calories led them to live longer, healthier lives. Since then, similar experiments of caloric restriction had shown to prolong the lifespan of worms, fleas, and even monkeys.”

Worms, fleas, monkeys, and a 1930s rodent study. 

Classic Oz. 

Are people actually reading this stuff and thinking that a worm study proves anything about the human lifespan?!

Fu*k! I think I just sprained my eyeballs from rolling them so hard.

If you don’t have the research, don’t make the claim. That’s pretty easy to understand.

Burning Fat with System 20

System 2020 says to start your day with a ‘fasted cardio routine’ and no food except for a black coffee that has MCT (medium chain triglyceride) oil in it.

The reasoning behind the coffee rule is that MCTs can help with satiety, and while you’re fasting, not feeling hungry is a good thing. He claims that MCT oil can burn fat, which is false AF. 

While it’s true that MCTs are burned more efficiently than other fats, that doesn’t mean that you should be consuming MCTs to ‘burn fat.’ It’s like when people eat tablespoonfuls of coconut oil to ‘burn fat.’ 


Should I say it louder for the people at the back? OMG! So annoyed right now.

Fat doesn’t burn fat. Nothing we eat burns fat. If it did, everyone would easily be at their ideal weight. But adding fat to your coffee in some random amount is not going to help you wake up the next morning weighing 10 pounds less.

It doesn’t work that way, people. And to give the impression that it does is irresponsible.

Weirdly, Oz admits that MCT oil doesn’t have a recommended dose, so you can put anywhere between 1 teaspoon and 2 tablespoons of it into your drink. Whoa. That’s quite the discrepancy in amount. 

And the fasted cardio routine? Fine for some, and for others, not so much. Research shows that in terms of weight loss, fasted cardio isn’t any better than ‘fed’ cardio. Fasted cardio may increase fat burning during exercise, but the end result in terms of weight is the same. 

Also, considering that followers of System 20 will have been fasting since 7pm the previous night, some people may be hungry enough that not eating will negatively impact their workout the following morning. 

Again, selling something with no appreciable evidence to back it up. 

We’re not off to a very good start. Moving on!

System 20’s Diet and Meals

Meals on System 20 consist of 1/2 cup of beans, 1 cup of greens, and 1 palm-sized protein twice a day. 

Snacks are all low-carb, and you’re allowed two a day as long as you follow the proper serving sizes. That means one egg, or 1 teaspoon of cocoa nibs (taste like burnt dingleberries), or 1 cup of broccoli, among others (refer to infographic above)

Looking at the two meals and two snacks, the total daily calories on this diet seem to be close to 1000. That is starvation. 

Not a diet? Whatevs, Oz.

But it gets worse, because of course it does.

System 20 cuts out all added sugars. Oz claims that ‘sugar has been proven to make you gain weight, increase your risk for heart disease and diabetes, and more.’ 

He puts a disclaimer on this by saying, “If you have a sweet tooth, that’s ok. System 20 still allows you to have sweet things like dark chocolate and berries – just not processed sugar.”

I hear fear and diet language in the words ‘allow’ and ‘processed.’ Sigh.

Let’s get one thing straight. Sugar isn’t a healthful food, but we don’t eat sugar on its own. People who eat a lot of sugar tend to eat a lot of ultra-processed foods as well. They tend to be more sedentary, and have an overall lower quality diet. 

So saying that ‘sugar makes you gain weight and have all sorts of terrible diseases’ is a gross oversimplification and stretching of the truth, which is actually this:

If your diet is based on ultra-processed foods, this can facilitate weight gain and lead to these conditions. 

But if you eat foods with added sugars in them a couple times a week and the quality of your diet overall is good, the sugar in your diet isn’t going to harm you.

Do you see how he’s using fear to sell this plan? It’s trendy to cut out sugar altogether, but honestly, it’s unnecessary, it sucks, and it’s not sustainable for most people. 

Oz loves the bullshittery that is apple cider vinegar, so of course it makes an appearance in System 20. 

He recommends taking two tablespoonfuls of ACV twice a day to help control blood sugars. Doing this will probably do nothing at all for you, since the effect is limited and studies on it are mixed and flawed. But that’s the Oz way, right?

Research like this and others on the effect of ACV and blood glucose gives ACV with a test meal of super-refined foods such as a white bagel, butter and orange juice, or mashed potatoes, none of which are on the Oz keto System 20 plan. 

He also links to his horrid slideshow of ‘Surprising Ways To Use ACV,’ which includes a recommendation to rub it directly on your teeth to remove stains.

Um. 10/10 dentists recommend NOT doing this. 

Lastly, there’s a cheat day once a week. He calls it a ‘day off.’

While I think cheat days are bullshit (read why here), Oz urges System 20 followers to take it even if they don’t want to. But, he does warn them not to ‘overdo it,’ which can ‘derail your progress.’

But let’s get one thing straight: if you’re not on a diet, you shouldn’t need a ‘day off.’

Am I right?

Especially on a low-calorie diet like this one, you’re likely to go nuts on your day off, eating everything in sight out of hunger. And I wouldn’t blame you one bit. 

My Review of Dr. Oz’s System 20

I think the most egregious thing about System 20 is not the plan, but the way Oz sells it.

I don’t have issues with low carb or intermittent fasting – they work for some people. 

But this is a starvation diet. There’s really no way else to describe it, and however Oz wants to package it, the contents are still the same: food restriction, plus language like ‘allowed’ and ‘rules,’ cheat days, and a focus on weight loss. He sells it like it’s easy and sustainable, when in reality, nobody wants cocoa nibs as a snack and giving people rules about eating rarely works in the long-term. Neither does starving them. 

The weight promise: ‘lose 20 lbs!’ is disingenuous, and a total red flag. He has no idea who is going to lose how many pounds, and the most important part – keeping them off – is unlikely.

His use of fear tactics coupled with shi**y research is disappointing AF. A doctor should know how to interpret research. I’m sure Oz does, but he counts on everyone else not bothering to do it for themselves. 

This is classic Oz – and like all other things Oz, should be avoided.

Want to read more? Check out my latest Biggest Loser Review.


  1. Sure looks like an IF diet to me! Plus MCT oil is not rec for lots of people. My nutritionist and DR told me not to go near it. Thanks for pointing out some of the other issues with this “diet”

  2. This is the best thing I’ve ever read. And I’ve read all the Haters Guides to the Williams-Sonoma Catalog (which is peak journalism, so that’s saying a lot). Thank you for making my day.

  3. YEAHHHHH…. this one is hard to follow too! It’s way to hard to follow and I seriously need something in my stomach to workout. And what about something other than cardio! Totally missing the point!

  4. Love your diet reviews. They keep me from being tempted to diet. I have been following the guidelines on the NIH website, and using their calorie calculating device, and I’m eating a ton a great food, not cutting out any categories of food, enjoying occasional treats, feeling completely satisfied, eating when I get hungry, and losing about a pound a week doing this! And it’s so easy and sustainable I plan to eat this way forever. I guess there is nothing glam and exciting about it, with thrilling promising of X number of lbs in X days, and not many are willing to pay money for “boring ” basic eating advice, but that is a shame, because, unlike the trendy extreme stuff, this actually works! Why people get excited about extremes is beyond me. I’ve long been of the opinion “if I can’t do balanced and moderate, how the hell am I going to be able to do extreme….and if you CAN do balanced and moderate, then why do I need extreme?”

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