Last week, a bunch of people were bellyaching on the networks about Karlesha Thurman, the recent California State University Long Beach grad immortalized in a photo capturing Thurman breastfeeding her infant daughter during her graduation ceremony. When she posted the picture to the Facebook page “Black Women Do Breastfeed” (I know, here we are again, having to explain what we do and don’t do), some viewers went apoplectic. Thurman’s chiders were apparently offended that she dared to bare a breast while helping her daughter live. (You can read and see plenty of that vitriol at Buzzfeed.)

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Thurman’s actions were not owed to a lack of home training or sluttiness, as some of her critics argued. The public breastfeeding was intentional. She was pregnant in her last year in college and delivered in her final academic semester. “She was my motivation to keep going,” Thurman wrote in an open letter about her daughter to her haters on Facebook, “so me receiving my BA was OUR moment.”

It wasn’t that long ago that Facebook was banning photos of breastfeeding, claiming they were vulgar. But Thurman is part of a movement to normalize public breastfeeding, resisting those who can only view breasts through a sexual lens. But breastfeeding is not only about resisting the policing of women’s bodies — and in Thurman’s case, black women’s bodies, whose policing basically became codified during the slave trade. It’s also a health issue, an environmental issue, and a justice issue as well.

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Perhaps people’s eyes would feel better comforted if she had pulled out a bottle to feed her baby some good old-fashioned Similac, or milk pumped from earlier that morning. But the nutritional benefits of direct, mother’s-nipple-to-daughter’-mouth feeding are well-established. Virtually all pediatric experts agree that breastfeeding is the indisputable best way to get your infant the nutrients it needs.

There are environmental benefits, too: No bottle means no plastic, which means no BPA and other harmful chemicals often found in plastics. It also means less waste, and less manufacturing and transport of feeding items, which all contribute to greenhouse gas emissions. As for formula, the amount of land and water used to produce the stuff — not to mention the pesticides and fertilizer — seems unjustified when a mother’s milk will do just fine. (Read more about the environmental benefits of breastfeeding here.)

And then there’s the equity factor. In the June 2012 Journal of Environmental Justice article, “A Life Cycle Approach to Food Justice: The Case of Breastfeeding,” sociologists Jeanne Holcomb from the University of Dayton, and Robert Todd Purdue and Joshua Sbicca, both from the University of Florida, find that poor mothers can’t afford to breastfeed much, often because they’re overworked.

“Disproportionately low rates of breastfeeding among people of color and the working classes are, at least partly, due to structural impediments,” write the sociologists, “such as the limited opportunities to breastfeed or pump breastmilk in low wage jobs, the lack of maternity leave in the U.S., and the fracturing of social support networks by the targeting of minorities in the War on Drugs.”

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Women making upwards of 350 percent above the poverty line are more likely to initiate and maintain breastfeeding. Meanwhile, just 67 percent mothers who make below 100 percent of the poverty line are able to initiate breastfeeding, while 19 percent can maintain it a year out from birth. For African American mothers, just 60 percent start out breastfeeding, while only 13 percent stick with it a year later — the lowest rates of all groups.

Part of the reason why black mothers are so hampered with this: The War on Drugs? Yep, drawing from the research of Lori Darby and Naomi Bromberg Bar-Yam, current director of the Mothers’ Milk Bank Northeast, Holcomb and crew point out that a “father’s favorable attitude toward breastfeeding was the most important factor in a mother’s decision to initiate” it. However, that kind of paternal support was lacking among black families due in large part to the over-incarceration of black men. “A disproportionate amount of reproduction-age African American men are incarcerated after conception or soon after birth,” write the authors, pulling a bunch of War on Drugs stats from Michelle Alexander’s must-read book The New Jim Crow.

Meaning, this issue is bigger than just Thurman. If anything, her selfie symbolized self-determination amidst a tide of factors that would rather render breastfeeding a privilege afforded mostly to women wealthier and whiter than her. That stand — for health, environment, and equity — alone deserves a diploma.