I don’t know if you’ve ever had periods in your life where you can’t sleep. I have, and I remember feeling pretty desperate about it. Your eyes want to shut all day, but when you get to bed at night, it’s like they’re held open by matchsticks. I’ve tried taking pills or potions during those times without much success, but maybe I just didn’t believe enough?
I read about a teenager in America who was suffering from insomnia. Like me, she’d looked up treatments for lack of sleep on her phone, and decided that melatonin was definitely going to work. She asked her mum if she could get her some, who told her she had some in the car. After taking the pill she fell into a deep sleep, could hardly get out of bed in the morning, and felt drowsy all day. Her mum had given her a tic-tac.
The belief that something works is often more powerful than whether the thing truly works or not. Non more so than low-carb diets. Among the many, apparent, benefits of a ketogenic diet, a complete decimation of any kind of hunger usually comes out on top. When enough people talk about how powerful the effect is, it’s hard not to take notice. However, just as I’m not going to throw tic-tacs down my throat next time I can’t sleep, I’m not going to tell my clients to give up carbs just because someone on Instagram says they should. So does keto really cure hunger? Find out why the science doesn’t fit with the low carb narrative.
Anecdotes should be taken seriously, but shouting something loud enough doesn’t make it true. The real science to back up the claims of a very low-carb diet eliminating hunger is iffy at best.
A review from a few years back did report a decrease in hunger in people following a ketogenic diet, but, on closer inspection, it was found to be a bit lacking. Firstly, it only contained three studies, which doesn’t make it much of a review. Secondly, only one study showed how much they were eating and if they were, truly, ketogenic.
To add to the lack of evidence that low-carb diets cure hunger, there is also, contrary, evidence showing that high-fat foods are more palatable, and therefore easier to overeat. Other studies have shown that people who eat high-fat foods are more likely to be obese than those who eat a lower-fat diet.
The real issue with these kinds of nutrition studies is that you can’t trust what people say. People routinely under-report how much they are eating, and over-report how much exercise they do. It’s not uncommon for people to say they are eating 50% less than they really are. It makes it hard to draw conclusions about hunger when people are saying they eat 1000 calories with zero interest in food but are actually eating twice that.
To answer the question as to whether keto really cures hunger, we needed a study that took place in a lab where every last detail could be controlled. That study didn’t exist, until now.
The researchers set to find out if people ate less on a low-carb/high-fat diet than a low-fat/high-carb one. To make sure that this study didn’t have the same failings as the self-reported ones, they took 20 people and admitted them as inpatients to a health centre where the lab could control everything.
- The 20 people were randomly split into either a keto or low-fat group.
- Both diets were minimally processed and whole food-based but the keto diet was 75% fat, with 10% carbs, and the low-fat diet was 10% fat and 75% carbs.
- Protein was the same between the two diets.
- They could eat as much as they wanted; stopping when they were full.
- Once they had been in one diet group for two weeks, they switched to the other one.
Keto logic says that people would have eaten less on the low-carb diet and consumed way more on the carb-heavy one. If that happened, keto would lead to significant fat loss while carb eaters would gain weight. That didn’t happen.
While both groups lost weight, the low-fat diet made people lose fat, while the keto group only made them lose water.
The real kicker is that when eating keto, people ate 689 calories more per day on average than they ate on the low-fat diet.
Sometimes the things we believe might not really be true. That’s ok. Because now instead of believing that it’s keto giving you all the magic, maybe it’s something else. I don’t know, maybe you’re magic. Either way, now you know keto isn’t affecting your hunger the way that you thought, you could try something else. Or you can stay with it if that’s your thing. It’s all fine with me, but the ball is in your court, and that’s always a good thing.
If you find a super-low-carb diet easy to stick to then there are very few reasons why you shouldn’t eat that way. However, before you jump onboard your new low-carb life or tell the world how much better it is than everything else, learn the facts. Despite what you’ve heard or read on the internet, keto doesn’t cure hunger.