Why Are Women More Likely to Be Obese Than Men?

In almost all countries, women are more likely to be obese than men. The economists Anne Case and Alicia Menendez set out to learn why, using data collected from a township outside of Cape Town, South Africa. Here’s what they determined:

1. “Women who were nutritionally deprived as children are significantly more likely to be obese as adults, while men who were deprived as children face no greater risk.”

2. “Women of higher adult socioeconomic status are significantly more likely to be obese, which is not true for men.”

These two factors, Case and Menendez write, fully explain the difference in female/male obesity rates they found in their sample. But there is a third point as well:

3. “Finally (and more speculatively), women’s perceptions of an ‘ideal’ female body are larger than men’s perceptions of the ‘ideal’ male body, and individuals with larger ‘ideal’ body images are significantly more likely to be obese.”

Although this research was done in a setting far removed from the typical U.S. town or suburb, Case and Menendez’s findings seem well worth thinking about for anyone here who is trying to fight obesity. Another issue to explore further might be whether obesity has a large cost for a woman when she is unmarried, but less so when she is married — although one could ask the same question of men.

It is perhaps also worth noting an obvious fact here: Case and Menendez are both women, and have produced here what looks like an important piece of research that concerns women. Emily Oster also comes to mind as a woman who does important research concerning women. Which leads me to wonder:

1. Do male economists tend to do too little research on women’s issues?

2. If so, shouldn’t there be many more female economists?

(If this subject is near to your heart, the Ten Principles of Feminist Economics may be worth a look.)


Wow - talk about over analyzing a question for which there is a very simple answer. All your reasoning is just speculation if not inaccurate. However, I feel no need to argue these points but get down to the real reason behind this: Hormones. Simply put, higher testosterone levels with low estrogen levels lead more lean mass. When estrogen levels are high and testosterone low, the body tends to store more fat. Given the natural level of these hormones in both men and women, it is pretty easy to come to a conclusion as to why more women are obese than men.


I believe the rates are slightly higher for men in this country, which actually fits somewhat well with the findings in other countries. Here, women have a lower ideal. Though the first finding is particularly worrisome considering the trend of younger and younger women to intentionally nutritionally deprived themselves.

Imperfect information or a high discount rate?


That's very interesting. My casual observation has tended to be that women from lower on the socio-economic ladder tend to be heavier than women who are higher--it costs money to be thin when junk food is cheap and high quality produce, health club memberships, and other, shall we say, "thinness support mechanisms" like diet pills and personal trainers are expensive.

But then, my casual observations tend to be of other young women who are between the ages of eighteen and thirty and nearly all of whom are unmarried and active in the dating scene. Given the premium our society places on thinness in women, it might indeed no longer be "worth investing" in thinness once a woman has acquired an appropriate spouse...at least until the time comes to find a new one.


And this study has more merit than studies on obesity within the medical field how? Within the US, the poor tend to have higher obesity rates exactly for the reason why Legaleaglet notes- junk food is cheaper. There is an incentive to eat less healthy.

Seriously, economists sometimes baffle me; here they are, touting around their ruler for every question under the sun when honestly, someone else has perfected a better tool to measure, predict and control for the question under purview. Just because economists can't be bothered to read the medical literature, doesn't mean they need to reinvent the BMI.


Actually, Silvanus, BMI was invented by an economist, not a doctor. (it was originally an actuarial statistic which is why it's fairly accurate as a health gauge among populations but meaningless in many individuals)


BMI (the measure often used to measure obesity) is a bad measure, and especially so for women. BMI accounts for height but in a way that favors tall people (I'm 6'5 myself). Being short and overweight/obese is "easier" if you are short due to the construction of the measure. Women are, on average, shorter than men and should (according to forementioned claims), thus, be obese more frequently.


Just checked out the "Ten Principles of Feminist Economists." Most of them seemed to be pretty debilitating attacks on any claims that economics can make to universality. But I think even economists (Dubner...you admitted this in a video recently) would agree that the principles of economics do not outline a universal system for analyzing human decision making. Otherwise we would live in a deterministic world.

Trouble is....these Feminist Principles outline something which is not economics at all, more of an anti-economics based on a post-structuralist world view. Do feminists seek to create quantitative models for the behavior of people based on the principles they have outlined, or do they only seek to deconstruct the ones that economists propose (when everyone knows full well that they are approximations)?

The other thing I'm confused about is that feminist economics is not a well defined science since there is not one set of "principles" from which it works. It's interdisciplinary, amorphous. How, then, can the subject be treated rigorously without a regression to either 'common sense,' or the principles of some other discipline, such as historical study or literary analysis?



The BMI also doesn't take into account the possibility that you may be muscular as opposed to fat (and muscle is more dense than fat too). I'm pretty certain that most rugby/American football players would be classed as "overweight" or "obese" according to the BMI. Of course, you tend to get more muscular men than muscular women, which would probably fudge the stats.

Rick L

My assumption has been that obesity is positively correlated with wealth in under-developed countries and negatively correlated with wealth in developed countries. In the first case, calories are expensive. In the second, calories are cheap. (Nutrients, on the other hand, are often prohibitively expensive to the poor in any country.)


Also somewhat confounding is the body fat difference between men and women. BMI does not depend on sex, but healthy women have 5% more body fat than healhty men. I'm not sure if BMI comparisons take this into account.


Evolution and natural selection go a long way towards explaining obesity. Our ancestors who ate as much food as possible whenever possible, survived famine and lived to pass along those "eat a lot" genes to us. Now that we have such easy access to calories, obesity is an epidemic.

The "eat a lot" gene was more important to women for survival of famine. Men could more easily go out and find food on their own. Women were often saddled with babies and young children, and had to build up enough calories to sustain breast feeding through famine. Over eating has been a successful survival tactic for the majority of human existence, particularly for vulnerable mothers.


Do male economists do more research on male economics than female economics? Do most female economists do research on female economics? If not most, is it unbalanced?


Having looked at what passes for "feminist economics", I'd like to potentially go off-topic and offer a possible eleventh principle, based largely on evolutionary psychology.

The fundamental paradigm of human sexual intercourse is prostitution. (1) Being an economic activity, it is inherently adversarial, with the buyer wanting to pay less and the seller wanting to provide less. (2) There are significant differences between men and women concerning the average optimum length of the contract. (3) On average, it is more important to women than to men that they control when the contract can broken off.


isn't the obvious answer that more men are dependent on their fitness level for employment? I don't see too many obese landscapers.


A couple of good points have been made already...

- Women are shorter/smaller than men, which means a smaller amount of weight gain accounts for a larger % of increase on the BMI scale

- Evolutionarily speaking, women might have had a tendency to eat more/maintain more body fat due to differences in the tasks of men and women

I was speaking with a co-worker the other week and her theory was that women have a natural tendency to put on weight more easily because body fat helps protect the woman and the baby during pregnancy...

while I don't take this for scientific fact, I think this is a fairly astute theory.

Janet V

Evolution also requires females to be able to store more energy to conceive, birth and nurse babies. I seem to recall reading the actual body fat percentage (10 percent?) that is the baseline for successful conception.

Which is why, I'm sure, all these rail-thin actresses have to adopt. At 2% body fat, they're simply not going to conceive.

I also agree with poster #13, Damon, that even now, men tend to engage in more physically demanding labor that builds muscle mass and, if they eat even marginally healthy foods, will keep them at lower weights.

I'm sure much of the adult obesity problem has to do with sedentary work places with extra loads of stress that lead us to seek solace in food, not exercise.

David Sickmiller

If "individuals with larger ‘ideal' body images are significantly more likely to be obese," that suggests that the American society's unrealistic ideal body shape actually helps fight obesity! That must make Kate Moss a humanitarian.


Should the title of this not be Why Are Women Outside Cape Town SA Are More Likely to Be More Obese Than Men Outside of Cape Town SA? Or would that just not sell like reference to your entry today of the story title with Bush Sr in the White House not counting his years as VP?

- Minh


As the article suggests that this is true in all countries, and not just in South Africa, this may be irrelevant.

However, I was a Peace Corps volunteer in South Africa for two years, and the general rule there was that male volunteers would lose weight and female volunteers would sustain or gain weight. This was, we were told, because the staple food, pap, is almost 100 percent carbs, which men can apparently digest or burn more quickly than women.

I don't know anything about nutrition, but I can attest to the fact that my male friends and I slimmed down quite a bit (with disappointing results when coming back to the U.S.), while our female colleagues, for the most part, did not. In my village, too, there were many more obese women than men. I always attributed it to the pap-factor.

Perhaps this could explain some of the data in developing countries where the staple food is so starchy?



My 2 cents on this is that especially in couples, men and women are often served (or give themselves) an equal amount of food, when men generally have higher metabolic rates allowing them to eat more. The extra calories hit women harder b/c their caloric requirements are less.
Perhaps women in higher socioeconomic groups take an especially heavy hit compared to men because they are at more sit-down restaurant dinners, where you're presented with equivalent amounts of good food sitting there right in front of you for a decent stretch of time. You're talking, having a good time--eat another couple of calamari, get that extra drink, etc... I think the best solution is to simply stop eating when you're not hungry and keep those eyes off his plate. Easier said than done. And look at the upside--he might be able to eat all that steak at one sitting, but you just got dinner and tomorrow's lunch for the price of one meal.