Can skipping breakfast cause heart attacks?
A recent study published in the Journal of the American College of Cardiology suggests that U.S. adults who regularly skip breakfast are at an increased risk of atherosclerosis and cardiovascular disease. With the increased popularity of intermittent fasting and supporting research that shows health benefits of fasting, why does this research state the opposite?
THE MOST IMPORTANT MEAL OF THE DAY? We’ve known for decades that kids who eat breakfast perform better in school and score better on IQ tests. Personally, I’ve believed for years that breakfast was the most important meal of the day. I regularly had a vegetable omelet that set the tone (and my insulin control) for the day. However, from an ancestral perspective, humans are able to subsist on a number of different dietary patterns that allow flexibility on food timing and availability. Some cultures eat a single large meal at the end of the day and others graze throughout the day. It makes no sense for our species to develop a chronic disease as a result of skipping a meal. So what does this latest study mean?
IT MEANS NOTHING. A quick look at the methodology shows that data was obtained from the NHANES (National Health and Nutrition Examination Survey) between 1988 and 1994. About 6,500 individuals who reported their food intake during those years were followed for 17 to 23 years and if they died, the researchers tried to find a link with their breakfast habits. Indeed, about 2,300 participants died, 620 of them from heart disease. With statistical pay, it was found that those who never ate breakfast (about 5% of the study sample) had an 87% higher risk of having a heart attack compared to those who ate breakfast every day (59% of the study sample).
HOW MANY APPLES DID YOU EAT THIS YEAR? There are MAJOR limitations to perpective studies. The NHANES study used a food frequency questionnaire that asks you to estimate how many apples you ate in the last year. It does this by asking you to remember how many you had this week (the week of the day on which you answered the questionnaire). If you had 4 apples that week because they were in season, then it would be assumed that you had 208 apples that year (4 apples x 52 weeks). Then we’ll see if those 208 apples you ate every year for the last 23 years (because that’s what we assume you ate based on the information you provided) is associated with any health condition you developed during this time.
Do you see how this data makes no sense? Can we assume that you eat the same way now as you did 23 years ago? If you skipped breakfast regularly in 1988, does that mean you’re still skipping breakfast?
Having a HUGE data set like the NHANES study leads to an exciting opportunity to play with numbers and statistics. But any information gleamed from it has very little relevance to real-world human lives. When it comes to food and nutrition, humans tend to have a pesky tendency to practice free will. This is pretty annoying to scientists who need to control variables in order to accurately test an effect. Without controlled conditions, all we have is statistical tools and tricks to try and account for variance.
WHAT’S FOR BREAKFAST? Even though the information was available, the researchers decided NOT to investigate the nature of the breakfast. So whether you regularly ate Pop-Tarts or a vegetable omelet in 1988, it still meant that you had a lower risk of having a heart attack compared to those who ate nothing. If that doesn’t make sense, it’s because it doesn’t. Studies using unreliable data produce unreliable results (the whole garbage in – garbage out kinda stuff).
THE HEALTH HALO EFFECT. In 1988, dietary fat was still the enemy. My doctor would’ve told me to eat less butter and eat more All-Bran. If I ignored his advice, I would probably ignore his advice about smoking, drinking, and eating fast food. I would probably also skip breakfast. Indeed, the study showed that between 1988 and 1994, most people who skipped breakfast were former smokers, heavy drinkers, physically inactive, and also had poor diet quality and low family income. We can try really hard to account for these confounding variables with statistics, but ultimately, it’s near-impossible to tease apart the effects of breakfast-skipping from their unhealthy lifestyle.
INTERMITTENT FASTING. Health critics have already started comparing how the “harmful practice” of skipping breakfast is different than the healthy practice of intermittent fasting. It’s not. An unhealthy person who skips breakfast isn’t going to become healthier.
Practiced properly, intermittent fasting has been shown to be associated with long-term weight loss and better outcomes in triglycerides, total cholesterol, low-density lipoprotein cholesterol, blood pressure, glucose, insulin, and C-reactive protein (inflammation). That means eating all your caloric and nutrient requirements within a shorter window of time. And your food should be healthy and minimally processed. The common practice is to eat all your food within an 8-hour period, say between noon and 8pm, which means skipping breakfast. Don’t worry, you won’t die of a heart attack.
IGNORE THE MAN BEHIND THE CURTAIN. Nutrition is a minefield of conflicting information and science is trying it’s best to make sense of it. Unlike chemistry and physics, there is no set of foundational laws on which to test a hypothesis (there’s no perfect human diet), so we’re left to use whatever information we have and whatever funding we can get to try and get answers. Studies based on bad science are much more common in nutrition (can it even be considered a science if there are no natural nutritional laws?) than in any other quantitive field. My advice is to place more importance on controlled, randomized, double-blind studies and less on observational studies, but unfortunately, that’s impossible when we want to study chronic lifestyle diseases. Instead, ignore the sensationalist headlines and look at how the study was done, how it was funded, and how it was interpreted. Then use your well-informed better judgement to come to a conclusion on how this relates to you as a pesky free-willed individual with no natural laws to follow.
