Low Fat or Low Carb Diet: What’s Better for Weight Loss?

The low fat vs. low carb diet debate rages on – and you’ll never guess what the result is….
This ongoing debate was recently re-fueled by a new study that claims to have “cracked the code” on the debate once and for all: that low fat or low carb diets are equally good for weight loss.
A couple weeks ago, I wrote a blog post on a similar topic, The Best Diet for Weight Loss and if you wanna check that out, go here. 
As for this study looking at a low fat or low carb diet for weight loss, here’s what I’ll say above and beyond last week’s post:
1. In general, diet studies are hard to do if you want to do them really, really well. They take oodles of time, a whole bunch of smart people, a metabolic lab, and mountains of money.
2. This isn’t the first or last time this type of study will be done. And I’m glad they’re being done! Don’t misunderstand me; this research is important. It adds to the body of work out there. Especially in the low fat or low carb debate.
And these studies are not easy. And I think researchers are, in general, doing the best they can. But I think it falls apart when it gets positioned in the media as an “all or nothing”, “head to head”, definitive answer to one of the most complicated questions out there.
low fat or low carb diet

In this study, the researchers classified "low carb" at 30% carbs, 45% fat and 23% protein. The "low fat" group was 48% carb, 29% fat and 21% protein.

3. Beyond the scope of this post is getting into the difficulty of controlling for so many variables in a study like this (some impossible to control) and they had the participants perform glucose tolerance tests and found no difference but I wouldn’t think you would see much variation (unless they had prediabetes or diabetes, which the subjects did not)
4. I do LOVE that they give the details on the percentage of carbs, fat and protein though. That was awesome!
Even though we know it’s caloric deficit that causes weight loss, regardless of where the calories come from (carbs, fat or protein), I’m fascinated by the key role that high quality carbohydrates play in blood sugar regulation, prediabetes reversal, lean body mass (muscle) development, energy, and gut health.
In this study, the researchers classified “low carb” at 30% carbs, 45% fat and 23% protein. The “low fat” group was 48% carb, 29% fat and 21% protein.
What do I recommend? If someone is not getting what they want (prediabetes remains, no muscle development with hard workouts, ++cravings for sugars, etc), then I suggest aiming for 40-45% carbs, 30% fat and the rest, protein.
how many carbs should I eat

So yes the debate will of course, continue to rage on. 

The question remains: what direction will you go? For so many of us, the switch to a lower (but not too low) carbohydrate diet makes all the difference we were looking for.

Here’s a message I got from someone who really took this 40% carbs suggestion and ran with it:

If you’ve tried the extreme low carb route and feel like it’s just not something you can maintain or you suspect that maybe, just maybe, cutting out all carbohydrates just isn’t the way to go, why not try something in between?

Embrace healthy carbohydrates as part of your way of eating so you can lose weight and reverse your prediabetes.

You can do this!


how many carbs should I eat


Gardner CD, Trepanowski JF, Del Gobbo LC, Hauser ME, Rigdon J, Ioannidis JPA, Desai M, King AC. Effect of Low-Fat vs Low-Carbohydrate Diet on 12-Month Weight Loss in Overweight Adults and the Association With Genotype Pattern or Insulin SecretionThe DIETFITS Randomized Clinical TrialJAMA. 2018;319(7):667–679. doi:10.1001/jama.2018.0245

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The Best Diet for Weight Loss3 mindset shifts to make before you reverse your prediabetes