Michael Seifert of the Rio Grande Valley Equal Voice Network said there is a direct correlation between hunger due to poverty and obesity.
Low-income people have less access to healthy, more expensive food and are becoming ill with deadly diseases like diabetes.
"Obesity and diabetes is extraordinarily expensive to the whole community, just as eating healthy is extraordinarily difficult for people to afford, that don't have that kind of disposable income," Seifert said.
A room full of spectators viewed the documentary A Place at the Table Thursday in Brownsville, which deals with hunger and obesity in the U.S. today.
Sister Phyllis of Projecto Juan Diego, said it's going to take a systematic change to impact these problems.
She added it could start with stores lowering the price of healthy foods and increasing the price of unhealthy ones.
"In the long run we're only hurting ourselves - we're spending more money on healthcare, Sister Phyllis said. If we could help get better foods for (low-income people) at a cheaper price, then they could be healthy, productive people and we'd have a better economy."
If there is no change, it's predicted that 50 percent of American children will end up with diabetes.
"We've seen children who are only 5 or 6-years-old and weigh 200-300 pounds," she said.
An inadequate diet is not only causing childhood diabetes at a ramped rate, but it's also affecting their development.
"(It affects) retardation, they're mental condition worsens after they don't have food - the proper types of food - and it really puts them behind a lot, Sister Phyllis said. We're going to pay much more health care,