5.17.2018

Is It Healthy to be Catholic?



Religion and health are a thing. There is even a journal devoted to the topic. The correlations between being religious and being in good health are numerous (extensive meta-analysis here). Religious people are less likely to smoke and more likely to exercise than non-religious people. Religious people eat healthier diets and have lower blood cholesterol levels than the non-religious. Yet, those healthier diets and more exercise have not led religious people to necessarily have lower body weights, on average, than the non-religious. Healthier lifestyles of religious Americans do appear though to impact heart health and blood pressure relative to the outcomes of non-religious people in the country. The religious also have higher functioning immune and endocrine systems, on average. Religious Americans are even less likely to get cancer than the non-religious and when they do get a diagnosis they often have a better prognosis for recovery. All of this leads to a rather surprising conclusion:

“The most impressive research on the relationship between R/S [religion and/or spirituality] and physical health is in the area of mortality. ... At least 121 studies have examined relationships between R/S and mortality. … Considering the 63 methodologically most rigorous studies (quality ratings of 8 or higher), 47 (75%) found R/S predicting greater longevity (two at trend level), whereas three (5%) reported shorter longevity. Another systematic review and two meta-analyses have confirmed this relationship between R/S and longer survival. The effects have been particularly strong for frequency of attendance at religious services in these three reviews. Survival among frequent attendees was increased on average by 37%, 43%, and 30% (mean effect being 37% across these reviews). An increased survival of 37% is highly significant and equivalent to the effects of cholesterol lowering drugs or exercise-based cardiac rehabilitation after myocardial infarction on survival.”
–Harold G. Koenig, M.D., Duke University, “Religion, Spirituality, and Health: The Research and Clinical Implications

The potential pathways for these outcomes are numerous. Religious people tend to be members of religious communities and these offer support in a variety of ways. Being religious may also reduce stress and have other positive psychological benefits that are related to physical health outcomes. Religious people, on average, also appear to be less likely than non-religious people to engage in behaviors that come with increased health risks.

But how healthy is Catholicism? According to the General Social Survey (GSS) the average Catholic adult male is 5 feet 8 inches and weighs 189 pounds. The average adult female is 5 feet 4 inches and weighs 158 pounds. Body Mass Index (BMI) combines this information into a single number that indicates whether one is underweight, normal weight, overweight, or obese. The average Catholic adult has a BMI of 27.2. This is lower than people of other affiliations. Overall, 36% of adult Catholics are of a normal weight (a small percentage are underweight). About four in ten are overweight and about a quarter are obese. Again, these numbers are generally better than those of other religious affiliations and similar to those with no religious affiliation (“None” are also disproportionately younger with an average age of 40.6 compared to 47.7 for Catholics and 50.5 for other Christians). As existing research shows, the GSS confirms that religion and spirituality are not linked to lower weights. However, among the religious, Catholics appear to be the least likely to be obese.

Most Catholics say they are in excellent or good health and are more likely to say this is excellent than those of other religious affiliations. Those without an affiliation are just as likely to say they are in excellent health. There is a relationship between one’s BMI and their self-reported health. Americans of a normal weight are most likely to report being in excellent or good health. Those who are overweight are less likely to do so and those who are obese are least likely to self-report this.


Catholics are less likely than those of other religious affiliations to report they have ever been diagnosed with high blood pressure, arthritis, depression, or diabetes. Those without a religious affiliation have a similar health profile to Catholics with an additional reduced risk of arthritis (again likely related to average age differences). Here again, with each illness, the higher your BMI, the more likely you are to have had a diagnosis. Thirty-eight percent of obese adults have been diagnosed with high blood pressure compared to 13% of those with normal weights. Twenty-two percent of obese respondents indicated they had a diagnosis of arthritis compared to 10% of those with normal weights. Fifteen percent of the obese have diagnosed diabetes compared to 4% of those with normal weights. Even depression is slightly more common among adults with obesity than those with normal weights (18% compared to 13%).


Thirty-eight percent of those with normal weights report that they are very happy (an additional 55% are pretty happy). Only 28% of those with obesity say they are very happy (61% say they are pretty happy). Christians in America, whether they are Catholic, Protestant, or some other affiliation, are more likely than those of other religious affiliations or no affiliation to say they are very happy.


While the GSS offers only one snapshot for these questions it is a remarkable one in that Catholics appear to be among the healthiest of Americans in body and mind. We can assume spiritual health likely correlates well with these aspects. The GSS does show that Catholics who attend Mass more frequently are more likely than infrequent attenders to say they are very happy.


Overall differences in health between Catholics and others are small but consistently positive. While no one should be writing prescriptions for Catholic baptisms yet it does appear that there are certainly no ill health effects from being a member of the faith in the United States. 

Update: I had a reader ask about running regressions and I took a look with OLS and Logit (where appropriate) to test the findings further. Catholics, controlling for age, gender, and years of education have a lower BMI (by 0.83) than non-Catholics (p = .03). Catholics are also less likely than non-Catholics to have been diagnosed with hypertension (p = .01). Note that non-Catholics includes those with religious affiliations and those without a religious affiliation. The relationships between Catholicism and self-reported health, arthritis, depression, and diabetes do not achieve statistical significance controlling for these other factors. More highly specified models may reveal more but it is safe to say two important health factors, BMI and hypertension, passed regression analysis with standard controls. There is indeed something more here to explore...

Doctor photo courtesy of Alex Proimos.