When the City Council put a referendum on the November ballot to impose a 1-cent-per-ounce tax on sugar-sweetened beverages, soda companies poured at least $2.5 million into efforts to defeat it.

African-American organizations in the city, like the Black American Political Action Committee and the Richmond chapter of the N.A.A.C.P., joined the industry, arguing that the proposal was paternalistic and that lawmakers had failed to consult with their community before putting it to voters. Some used even stronger language, stoking divisions in a city that had long faced tension between its black establishment and more liberal whites.

“They claimed it was racist — that here I was, a white doctor, trying to impose a regressive tax on black people,” said Jeff Ritterman, a former Richmond councilman and retired cardiologist who led the effort. “Even though we had data showing it would improve the health of African-American children, it was hard to get that message out.”

While some local N.A.A.C.P. chapters have been members of Americans Against Food Taxes, the national N.A.A.C.P., whose anti-obesity advocacy is financed chiefly by the Robert Wood Johnson Foundation, does not oppose soda taxes. In a resolution adopted at the group’s 2010 annual convention, the N.A.A.C.P. hailed its partnerships with beverage companies but also cited the foundation’s research showing that higher prices can drive people to eat fewer unhealthy foods. The resolution called for local chapters to pursue a range of strategies to reduce African-Americans’ consumption of products containing added sugars.

A Mutual Benefit

For nonprofit groups, especially those serving low-income communities, corporate grants and sponsorships can be a financial lifeline, underwriting programs, conferences and research. And as community groups serving blacks and Latinos try to tackle rising rates of obesity, many of them have chosen to team up with soda manufacturers and other food companies. Their preferred solutions often reflect those favored by the beverage industry: calorie labeling, nutritional education and expanded exercise programs.

“We have not been able to bring some of the older-line civil rights leaders along in our discussion of public health,” said LaDonna Redmond, a health activist and senior program associate at the Institute for Agriculture and Trade Policy, based in Minneapolis.

“They may understand the ties to food consumption and health,” Ms. Redmond added. “But they’re like so many Americans — they understand the problem but they don’t want to get involved to do something about it. They’re going to take the money and they say, ‘What’s wrong with helping our friends?’ ”