There’s something wonderful about breakfast. Maybe it’s the fact that it’s the only meal of the day where it’s socially acceptable to drink your own body weight in coffee. Maybe it’s the delightful knowledge that you’ve actually managed to get out of bed today. Of course, it could be that we all love breakfast because we have been told by countless sources that it’s the best and healthiest meal of the day.
And, according to recent headlines, breakfast is even more important than you might’ve thought. Across the world, media sources from the New York Times to CNN to the Daily Mail have been yelling that breakfast is not just about getting a good start to the day, it might be preventing heart attacks as well! Apparently, skipping breakfast increases your risk of stroke and heart disease by 87%, making it that much more important that we all chow down first thing after waking up.
But before you start gobbling down Cheerios in the morning, it’s worth noting that there’s more to the story than you may’ve heard.
It turns out that breakfast probably isn’t saving your life after all.
The study that all of these headlines are talking about was what’s known as a prospective cohort. Basically, the researchers took a group of people, measured them on a wide range of variables over time, and then looked decades later to see what factors influenced health outcomes like heart disease and death. In this case, after controlling for a wide range of factors, they found that those people who reported never eating breakfast were 87% more likely to die from heart disease compared to those who at breakfast every day.
When I put it like that, breakfast does sound pretty rosy.
The study was also very well done, controlling for a number of things that might’ve gotten in the way of their conclusions, using a big sample, and generally doing the things that epidemiological research is meant to do. There does seem to be an association between breakfast and cardiovascular death, at least from this research.
But unfortunately for the breakfasters among us, there’s a bit more to this story. It seems that breakfast might not be as important as the headlines suggest.
The first important point is that a study like this can’t establish causation. There are simply too many factors that can influence both breakfast habits and heart disease to make any definitive claims based on an observational study like this.
I’ve written before about the perils of inferring causation from epidemiological research of this kind, but basically we can control for the things we know about, but we can’t control what we don’t know about or can’t measure. There may be factors influencing the results that we simply don’t know that we don’t know.
There’s also another issue. People who never ate breakfast were more likely to die from heart disease, but they weren’t more likely to die of any cause, or more likely to get heart disease. They were more likely to have a stroke, but the number of strokes was pretty small anyway so it’s hard to know what that means. It might just be that people who never eat breakfast get heart disease instead of, say, choking to death on their morning banana bread.
Also, the absolute risks were very small. The headlines reported an “87%” increased risk, but that was just relative: the absolute difference between people who never ate breakfast and those who ate it every day was more like 0.2%, which is not nearly as scary.
But even more than that, there’s a fundamental issue here: what is breakfast?
In this study, people were allowed to define for themselves what they meant by “breakfast”, which is a problem because that makes the results almost impossible to interpret. Is breakfast the first meal of the day? The first thing you eat? Does it have to include “breakfast” foods? Is eating cold pizza at 2pm breakfast if you woke up with a hangover at 12 and have only had cigarettes since, or should that be brunch?
It’s pretty easy to see the problem.
The only thing we can really take away from this study is that people who say they don’t eat breakfast — whatever that means to them — are more likely to die from heart disease than people who say they eat breakfast every day. They are also more unhealthy in a lot of ways — they smoke more, drink more, weigh more etc — so it might just be that people who self-report not eating breakfast are just generally a bit less healthy than those who do.
There’s been quite a bit of research into breakfast. Studies like this one have previously shown links to obesity, diabetes, and general ill-health from skipping breakfast. However, it seems that when we actually try and get people to add breakfast to their day, the results are mixed. While there isn’t an enormous amount of research in the area, a systematic review from 2018 found that, on average, when people add breakfast to their diet they actually gained weight rather than lost it. Conversely, there have been some studies showing that people who skip breakfast may eat less each day, although that’s also a contentious finding.
And on top of all of this confusion, we have the problem that we still don’t really have a definition for breakfast. It means so many things to so many different people that it’s really hard to take one thing away from the idea.
When I was a shift worker doing overnight corporate security gigs, breakfast could mean a muffin and coffee or a pre-shift burrito depending on when I started. If someone had told me to make sure I ate breakfast for my health, I’d have just been confused.
Ultimately, it’s unlikely that breakfast has that big an impact on your health. It’s possible that eating healthily first thing in the morning might have a beneficial impact on your life, but skipping breakfast might be good too. The reality is that the best thing to do is probably the one that works for you.
Not very helpful advice, maybe, but a bit more true than the headlines.
So don’t worry too much about skipping breakfast. There’s weak evidence that it may be bad for you, but similarly weak evidence that it might be good for you too. Even if it is bad, the effect is pretty small, and doesn’t impact your overall chances of death or heart disease. If you’re worried about your diet, go and see a dietitian. They are the best placed to give you health advice that will be meaningful to you.
The headlines were wrong.
Breakfast probably isn’t that important after all.
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