This isn’t to say that avocado eaters are necessarily better than everyone else. But a study published on March 30 in the Journal of the American Heart Association (JAHA) delivered a heart felt message for all those who regularly “guac” their worlds with green and yellow goodness. The study found that people who had eaten at least two servings of avocados per week had a 16% lower likelihood of developing cardiovascular disease and a 21% lower likelihood of developing coronary heart disease.
Before you tell everyone to kiss your Hass, though, keep in mind where these findings came from and what the associated strengths and limitations of the study may be. This study was an analysis of what had happened to 68,786 women who participated in the Nurses’ Health Study (NHS) and 41,701 men who were part of the Health Professionals Follow‐up Study (HPFS) over the course of several decades. The NHS had begun in 1976 and had since enrolled 121,700 female registered nurses who were between 30 and 55 years of age, relatively healthy to start, and from 11 different U.S. states. The HPFS had commenced in 1986 and has since enrolled 51,529 male health professionals who were between 40 and 75 years of age, relatively healthy initially, and from all 50 U.S. states. Both of these studies didn’t focus just on avocado eating because, believe it or not, people do have other activities in life. But they provided a sizeable amount of data for this avo-cardiovascular study published in JAHA.
After completing initial questionnaires about their health including their diets upon enrollment, participants of both studies had to subsequently provide updates every two years. For the avo-cardiovascular study, a team from the Harvard T.H. Chan School of Public Health and Brigham and Women’s Hospital (Lorena S. Pacheco, Yanping Li, Eric B. Rimm, JoAnn E. Manson, Qi Sun, Kathryn Rexrode, Frank B. Hu, and Marta Guasch‐Ferré) analyzed data from these cohorts that were collected from 1986 onwards.
This study did rely on self-report of things such as avocado intake. Although people are probably not likely to lie deliberately about avocado intake since few schools and businesses have had avocado mandates, people aren’t always great about remembering what they ate. Heck, some people may not even know what’s currently in their mouths at the time without the help of a teleprompter. Nevertheless, the Harvard T.H. Chan School of Public Health team did start off their analysis by excluding those study participants who didn’t answer the questions about avocado consumption. That’s because it was difficult to tell whether these folks didn’t answer because they actually didn’t consume avocados, inadvertently skipped the questions, or were somehow trying to avoid avocado persecution. They also ruled out anyone who already had developed heart disease, stroke, or cancer or had daily overall caloric intakes that were unusually low or unusually high.
Over the course of 30 years, the study participants had a total of 14,274 reported new cases of cardiovascular disease. This included 9,185 cases of coronary heart disease events and 5,290 strokes. The research team did find significant differences between those who had eaten two servings or more of goodness per week versus those who ate less goodness. However, this alone wasn’t enough to toast the cardiovascular benefits of avocado. After all, eating avocados versus not eating avocados is probably not the only thing that these study participants did over the course of several decades. For example, some of these people probably had to buy and slice avocados as well. Therefore, the research team had to take into account other personal characteristics and regular behaviors that may have affected their cardiovascular risk as well, such as the person’s age, body weight, smoking status, physical activity, aspirin and other medication use, multivitamin use, menopausal status, postmenopausal hormone therapy use, and oral contraceptive use.
After statistically adjusting for these factors, the research team still found a 16% lower incidence of cardiovascular disease and 21% lower incidence of coronary heart disease among those who had had at least two servings of avocados a week compared to those who had less than that. They didn’t find significant differences in the incidence of stroke though. The analysis also revealed that replacing half a serving per day of margarine, butter, egg, yogurt, cheese, or processed meats with a comparable amount of avocado correlated with a 16% to 22% lower likelihood of developing cardiovascular disease. So rather than munching on that gigantic wheel of cheese while watching the latest episode of the TV reality show “Married at First Sight,” you may want to swap in some avocado instead.
Are such results grounds to avo celebration? Well, it wouldn’t be surprising for avocados to be associated with better cardiovascular health. Avocados are rich in good stuff such as vitamins C, E, K, and B6, riboflavin, niacin, folate, pantothenic acid, magnesium, potassium, lutein, beta carotene, omega-3 fatty acids, and fiber. The fat in avocados is the better variety too, the kind that keep your feeling fuller so that you don’t munch as much in between meals.
Nevertheless, statistical associations alone can’t prove cause and effect. Otherwise, the solution to the current climate change crisis might be training more pirates since global temperatures have increased as the number of pirates on the sea has decreased over the years, as I’ve described previously for Forbes. Correlations found in such observational studies can end up linking two things that are not really related when each of those things are actually connected to something else. For example, there might be other differences between avocado eaters and non-avocado eater besides being super awesome that may in turn confound the results. Let’s face it, avocado toast is not exactly the cheapest food available. Therefore, avocado eaters could have had on average more financial resources available. Or maybe they had healthier habits or surroundings in ways that weren’t factored into the analysis. Furthermore, those eating avocados may in turn have been eating smaller amounts of unhealthy foods. After all, a human tends to have only one mouth. So, from this study alone, it may not be clear how much of the value rested in what avocados directly offered versus what avocados may have been preventing people from otherwise eating. Therefore, “avocadon’t” draw much more from this latest study than it can really offer.
Ultimately, though, this latest avo-cardiovascular study does offer another slice of evidence that including avocados in your diet could be beneficial for your health. So there seems to be even more reason to “avocuddle” the green and yellow goodness. More studies could help better characterize the specific relationships between avocado consumption and cardiovascular health. And it may not be super difficult to find study participants who are willing to be fed avocados.