It’s easy not to think about where you get the food you cook each week—easy, that is, if you have a grocery store or big box stores nearby. But for the 20 million Americans who live in food deserts, where grocery stores with fresh produce are inaccessible, figuring out how to get things like meat or vegetables or even milk, can be a daily struggle. This can translate into higher rates of obesity, diabetes, and cardiovascular disease. 

These food deserts may be growing as big box stores like Walmart expand and as dollar chains like Dollar General and the Dollar Tree show up in urban and rural areas, undercutting local grocers with low prices and helping to drive them out of business. 

Now, the government is looking into whether the market power of giants like Walmart and the dollar stores is helping eliminate smaller supermarkets—and whether this violates a 1936 law, called the Robinson-Patman Act. The law essentially says retail giants can’t use their size to bully suppliers into giving them discounts and special deals that the suppliers don’t offer to other retailers. The power of the giants is something that affects everyone, not just people living in food deserts, according to Federal Trade Commissioner Alvaro Bedoya, who has been traveling around the country visiting independent stores in what would otherwise be food deserts and learning how the government could help them thrive. 

“The thing to remember is that when those independents go out of business, they are no longer providing the competitive pressure on the big box stores,” he told me. “And that gives the big box stores the ability to start raising the prices.”