The Vitamin #5: The Current State of the Carb vs. Fat Debate

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28 May 2020 | by Aadam


It’s Thursday which means it’s time for another instalment of the Vitamin. Every week I drop some knowledge bombs on your face to help you get to your goals quicker while avoiding all the misinformation.

Let’s get to it.


1) I’ve heard recommendations that one should eat at maintenance for a month or two for every 10% of body weight lost to ‘reset’ their weight set point. The idea is that this will result in more permanent weight loss. Is there any science to back up this claim? I’ve lost 100 pounds over the last year by eating at a consistent calorie deficit and never had the desire to take a diet break because I don’t feel deprived. My diet feels sustainable and I feel prepared for maintenance when the time comes. I’d hate to think I’ve set myself up for failure because I didn’t take diet breaks along the way. What do you think?

There isn’t any science to back up that specific claim. That is, weight set points can be reset by manipulating the diet. And neither will there be because you can’t.

Just to clarify, when I say you can’t reset your weight set point, I’m referring to the idea that intermittent breaks from the diet cause physiological changes to occur that eventually make maintaining a lower body fat percentage ‘effortless’ (according to the claims).

The only way to establish a new set point–and I use that terminology very loosely–so you can maintain a lower level of body fat is to build good habits that are conducive to weight maintenance. Regular exercise (structured workouts and daily movement). Ensuring the majority of your diet is filled with whole foods that are nutrient-rich and consuming adequate protein.

With all of that said, diet breaks are still something I recommend and use with my clients.

We know dieting leads to some hormonal downregulation that can make it harder to stick to the diet. A short diet break could, potentially, help reverse some of the negative side effects of dieting.

And if a 1-2 week break increases energy levels and lowers hunger, it helps improve adherence and motivation for the next round of dieting.

Lastly, and perhaps most importantly, it gives the client time to ‘practice’ maintenance. People become so obsessed with losing weight that the thought of never eating in a deficit is alien to them. Forcing them to increase calories and practice life after dieting reminds them of the ultimate goal (spoiler: it’s not the weight loss).

But whether you decide to implement a diet break is up to you. If you feel fine and things are progressing, then keep dieting for as long as you need to and implement a break when it makes sense, like coinciding a diet break with a holiday. You know, when we used to do stuff like that.


– The current state of the carb vs. fat debate

So there’s this journalist, right. And one day he realises we’ve all been lied to–it’s not the excess calories pelting humanity to a corpulent future where we all end up like the humans in WALL-E; no, it’s the damn carbs!

In 2002, the New York Times publishes his impassioned tirade against convention, and where he presents “The Alternative Hypothesis”: Obesity and all the chronic diseases of civilisation are not caused by overeating and sedentary behaviour but carbohydrates.

The article does so well it ends up on the front cover of the magazine and lands him a book deal.

Five years later, he publishes his book “Good Calories, Bad Calories.” Which goes on to become a best-seller and firmly places Gary Taubes at the forefront of the anti-carb movement.

But Taubes’ not done yet. He publishes more books vilifying carbs and sugar and finally, in 2012, he launches the Nutrition Science Initiative (NuSI), “a nonprofit dedicated to improving the quality of nutrition research.”

The goal was to conduct a number of studies to prove the Alternative Hypothesis, or what’s more commonly known as the Carbohydrate/Insulin Hypothesis, was a real thing and, I suppose, to convince himself the last decade of his life was’t for nought.

NuSI would find the world’s best researchers–even those that disagreed with them–and fund their experiments but leave everything else to the researchers. This would prevent any biases from seeping in and ensure the studies were legit.

And that’s where everything fell apart for Gary Taubes.

The first study, titled “Calorie for calorie, dietary fat restriction results in more body fat loss than carbohydrate restriction in people with obesity“, was published in 2015.

As the title suggests, the high-carb group lost more body fat than the low-carb group. But here’s the kicker: the high-carb group lost more body fat despite the fact their insulin levels were higher.

Of course, Taubes wasn’t about to take this lying down–he was way too committed now to let one silly study change his mind. He criticised the study and tensions began to mount between NuSI and the researchers.

Eric Ravussin, one of the co-lead researchers brought on by NuSI, told Wired Magazine that “It eventually just became us (researchers) versus them (NuSI).”

In 2016, Kevin Hall, the other co-lead researcher had had enough of their shit and decided to step down from his role with NuSI, and a year later published a meta-analysis comparing the effects of calorie-matched diets differing only in their carb and fat intake. ⁣ ⁣

The researchers included only those studies where subjects were provided with all of their food during the study duration while excluding all studies where subjects were provided with food menus or instructions on how to adhere to the diet.

This ensured any dietary nonadherence that could affect the results was minimised–basically, the researchers didn’t fuck around.⁣ ⁣ They found 32 studies with 563 subjects with dietary carbs ranging from 1%–83% and dietary fat ranging from 4%–84% of total calories.⁣ ⁣ The result? ⁣The low-fat diets resulted in a mean difference of 16g/d greater body fat loss. ⁣

‘These results are in the opposite direction to the predictions of the carbohydrate-insulin model,’ Hall concluded. ⁣

And that’s not all. Another randomised control trial published in 2018 by a different research group (Gardner CD et al., 2018) compared the effect of a low-carb or high-carb diet on weight loss after 12 months. The conclusion?

In this 12-month weight loss diet study, there was no significant difference in weight change between a healthy low-fat diet vs a healthy low-carbohydrate diet, and neither genotype pattern nor baseline insulin secretion was associated with the dietary effects on weight loss.

And that’s where things currently stand with the carb versus fat debate. When calories are controlled, there’s no difference in fat loss (or gain). So choose the diet that you can stick to. Everything else is noise.

– A profound comment from a client

My clients often say things that make me go “Woah, that was profound as fuck.” One such incident occurred last week and I thought it was too good not to share.

Something REALLY clicked for me this week about the fact that the body does NOT understand 24 hrs – but it DOES understand consistency over time (meaning weeks, months, years)”

You’ve heard me say this before, but your body doesn’t care about your goals but it does care about the effort you’re putting in.

If you’re putting in honest effort towards your goal, then there’s no reason the results won’t follow. So instead of stressing about how long it’s going to take, be more concerned about doing what you need to do every day to get closer to your goal.


How Low-Carb Diets Actually Work

Apropos to today’s email: in this #TBT article, I explain all the mechanisms by which low-carb diets lead to fat loss–spoiler: it’s not insulin.

Read the article

That’s all for today. Speak to you next week.

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