Rump for Joy

I am a curvy girl with a big butt. I hate it. I have a small waist, and it makes my butt look even bigger. I don’t care that the Kardashians have made big butts cool. I’d like to lose weight in that area. However, my boyfriend LOVES my butt and told me there’s research that says girls with bigger butts are smarter and healthier. Is that true? That can’t be true.

—Tushy Galore

Welcome to the science-inspired catcall: “Woooo, girl…you look like a nuclear physicist in them hot pants!”

Yes, there seems to be a cognitive edge in being a woman with a big caboose — provided you have a low “waist-to-hip ratio.” That’s professor-speak for women who have small waists relative to their hips — an “hourglass figure” like yours, as opposed to a body that’s more No. 2 pencil-esque or beerguttylicious.

Epidemiologist William Lassek and anthropologist Steven Gaulin find that being voluptuous in the way you are is associated with both being a bit smarter and having smarter children. To understand why starts with understanding “parent-offspring conflict,” evolutionary biologist Robert Trivers’ term for how it’s in each child’s genetic interest to suck as much in the way of resources out of their parent as they can.

This battle for resources starts early, which is to say a fetus is a little hog. It hoovers up its share of nutrients and then may go after some of its mother’s share, too — not so much that it kills her but maybe, “Hey, Ma, enjoy the gestational diabetes!”

Lassek and Gaulin note that this competition for resources is especially rough on teen mommies, whose own brains are still developing. Both the teen mother-to-be and her child are prone to having their cognitive development “impaired” — irreversibly diminished from what it could be — when she’s forced to compete for a limited supply of nutrients with the fast-growing fetusmonster.

However, Lassek and Gaulin find that women with bodies like yours seem to be cushioned — or, you could say, “seat-cushioned” — against this cognitive impairment, apparently because the butt and hip area serves as a supplemental food storage locker for the developing fetus. There’s a special kind of fat that gets deposited in this area — gluteofemoral fat.

This booty fat is different from and healthier than belly fat. It’s loaded with omega-3 fatty acids — especially DHA, docosahexaenoic acid — which we can only get from things we ingest, like seafood, walnuts, cooked spinach, and krill oil supplements. DHA is essential for day-to-day cognitive functioning in all people. And, Gaulin emphasized to me, it’s “the most important brain building resource” for little fetus people. He and Lassek controlled for things like parents’ income and education and the number of dollars spent per student and found mothers’ higher DHA to be the strongest predictor of kids scoring significantly higher on tests in math, reading, and science.

You’re packing more DHA than a woman who carries her fat Santa-style, but any woman can increase her DHA through diet, especially by eating fish. As for your desire to shave off some of Mount Buttmore, bad news: Gluteofemoral fat is extremely resistant to weight loss (as that basically would amount to throwing away some of your brain’s lunch).

But to lose weight overall — while feeding your brain and protecting it from cognitive decline — consider this from Lassek and Gaulin’s book, “Why Women Need Fat”: “The single dietary factor most strongly related to women’s weight gain was the amount of omega-6 linoleic acid in their diet.”

A major source of omega-6 is factory Frankenstein oils — polyunsaturated, heat-processed seed oils like soybean, sunflower, corn, and canola. (Extra-virgin olive oil is healthy — an omega-3 source.) And, surprise! Eating fish cooked in these omega-6-packed Franken-oils makes us “unlikely to retain the valuable omega-3 present in the fish.”

Getting back to your back end, it seems you owe it an apology. Maybe you were swayed in what you find attractive by the cadaverishly thin women that gay male designers send out to faint on the catwalk. Consider that you may be confusing body weight and booty shape in how self-conscious you feel about your behindquarters.

Now, whether men prefer heavier or slimmer women varies by culture. However, the late evolutionary psychologist Devendra Singh found that men across cultures overwhelmingly are hotter for the smarter-baby-producing hourglass bod that you have — though without any conscious understanding of why this preference evolved. (No, their penises didn’t put on their reading glasses and pore over Gaulin and Lassek’s research.)

Instead of longing for a body type that men don’t find as sexy, maybe resolve to start appreciating what you have — including your own special version of the trickiest no-win question a woman can ask a man: “Baby, does our future Einstein look fat in these pants?”