No, You Really REALLY Don’t Need To Eat Breakfast
Oh dear, it’s observational study oops time again: Causation and conclusions are drawn, where only loose associations and interesting hypotheses emerge. Meanwhile, the media hubbub may be harmful to your health.
The headlines blare: “Skipping breakfast tied to higher risk of heart-related death, study finds”. The study was conducted by researchers at a quality institution (The University of Iowa), and published in a respected journal (Journal of the American College of Cardiology).
Researchers looked at one-time interview responses from 6,550 participants age 40-75 in the NHANES (National Health and Nutrition Examination Study) between 1988 and 1994. The majority of participants (59%, or 3864) reported that they ate breakfast every day, 25% (1637) some days, 11% (720) rarely, and 5% (327) never. They then looked at 18 years of death registration data, which showed 2318 deaths, 619 of which were due to heart attacks or strokes.
Among the few never-breakfast-eaters, there were 41 cardiovascular deaths, which although a very small overall number and thus quite prone to error, was reported as a 87% higher risk than among always breakfast eaters. The researchers then drew the conclusion that skipping breakfast was associated with a higher risk of cardiovascular death, which is incorrect.
Here’s why their conclusions are all wrong, and it’s all in their own data: People who never ate breakfast were not only more likely to report an unhealthy diet and lack of physical activity, they were also more likely to have a history of smoking and heavy alcohol use, and—here’s the kicker on all of these skipping breakfast studies—to be poor.
The correct conclusion drawn in this study should be:
Participants who reported never eating breakfast were also more likely to have multiple risk factors for cardiovascular disease, as well as a higher risk of cardiovascular death. It’s not clear if an unhealthy diet, lack of physical activity, a history of smoking, heavy drinking, and/or being poor caused people to not eat breakfast, or if it’s the other way around.
Think about what we’re really measuring here. Could it be that people from a very low socioeconomic status don’t eat breakfast because they can’t afford it? Or maybe they’re working nights and the first meal they get is actually lunch, or maybe the only food they can afford is crap. Oh, wait, they said that, they reported an unhealthy diet. And little physical activity. And current smoking. And more drinking. Maybe people who stay up late partying, smoking and drinking, are less likely to wake up for a traditional breakfast? Maybe eating breakfast has little to do with anything
I’m far from the only one who disagrees with this study’s conclusions. All we can really say about it is it’s a bunch of loose associations, and several interesting hypotheses emerge, none of which are reflected in the headlines.
To really study the health effects of skipping breakfast, we’d want to conduct clinical trials where we controlled the variable of interest (not eating breakfast) and then studied specific outcomes (like things that have to do with cardiovascular health). Somebody should do that!
Oh wait, they did… Actually, we have numerous scientific review articles examining multiple clinical trials and summarizing the findings, like this 2017 article in Annual Reviews. Four human trials looked at the health effects of prolonging the overnight fast until lunch. I.E., skipping breakfast for 2 to 4 weeks, and found a 2% to 4% weight loss, as well as lower blood sugar and cholesterol, and several more looked at other forms of intermittent fasting. The authors conclude: “Modified fasting regimens appear to promote weight loss and may improve metabolic health”.
This excellent 2018 article in The Journal of Physiology and Pharmacology looked at 28 clinical trials of various IF regimens, and found across the board significant associations with weight loss, blood sugars, cholesterol, blood pressure… Check out Table 4, it’s pretty impressive. The authors conclude: “… intermittent fasting in patients with obesity (including those with coexisting Type 2 Diabetes) can lead to a reduction in body fat mass and metabolic parameter improvements. These beneficial effects arise not only from the loss of body mass, but also from the activation of metabolic pathways specific to fasting conditions.”
Yes, more research on prolonged fasting—like skipping breakfast– is needed, but it has to be well-conducted clinical trials, not observational data. So ignore the headlines and do your own research… And know that you do not have to eat breakfast.