A recent Sociology of Health and Illness paper finds that reading and exercise appear similarly beneficial in terms of BMI — and this leads to a befuddled analysis:
The study uses survey data from 17 nations, most of which are in Europe. In each country, a representative sample of the population was asked not only about height and weight, but also about time spent in a variety of activities. These included reading, going to cultural events, socializing with family and friends, attending sporting events, watching TV, going shopping, and exercising.
A scale that measures interest in ideas, art, and knowledge — by surveying the amount of time spent reading, attending cultural events, going to movies, and using the Internet — is associated as strongly as exercise with a lower body-mass index, or BMI (a measure of weight relative to height). In other words, reading and exercise appear similarly beneficial in terms of BMI.
In contrast, people participating in other activities such as watching TV, socializing, playing cards, attending sporting events, and shopping have higher average BMI. Although time spent reading and time spent watching TV both expend few calories, one is associated with lower weight, and the other with higher weight.
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More highly educated people tend to both read more and weigh less. Perhaps knowledge gained from schooling gives insight into the importance of proper weight for good health. In addition, mastering difficult coursework in college can help build confidence in one’s ability to reach difficult goals – including managing weight.
The data for 17 nations examined in the study did not allow for accurate measurement of family income. Yet, it’s reasonable to think higher income helps maintain body weight in several ways, such as allowing consumers to buy expensive fresh fruits, vegetables, and lean meats rather than cheaper starchy and fatty products.
That said, the association between BMI and reading and related activity can still be found even after controlling for education and other measures of socioeconomic status.
Perhaps the key is that groups sharing similar intellectual and cultural interests likely also share common lifestyles for health. It makes sense that members of a social network will share many ideals, and some of those ideals may relate to health and body weight. (See this article for another take on the importance of friends and families in fighting obesity.)
Among groups that most enjoy reading and cultural events, a healthy lifestyle and thinness may bring respect, while unhealthy behavior and being grossly overweight may bring criticism, even shame. If reading and related cultural interests lead to social networks of like-minded people, peer influence may help in maintaining or losing weight.
I’m sure it’s the esoteric knowledge of diet and exercise that the young members of the cultural elite had revealed to them in college — knowledge that has been hidden from the masses to keep them ignorant and pliable. They must never learn that a 44-ounce soft drink is bad for them, or they will challenge our power!