The smaller the paycheck, the bigger the belly, say many researchers who study poverty and obesity.
It might seem like a paradox, but not having enough money for food doesn't mean the poor are skinny. The opposite appears to be true: The lower-income are more likely to be heavy than the well-to-do.
"Obesity is an economic issue," said Cyndi Walter, manager for the California Department of Public Health obesity-prevention program, Project LEAN. Eating well is beyond the reach of many California residents, she said.
It's easy to make the connection in the central San Joaquin Valley. At least 20% of adults in the region live in poverty, and about 30% are obese. Statewide, 13% are poor and 23% are obese, according to U.S. Census data and the 2007 California Health Interview Survey.
Health experts say there is no shortage of reasons why poverty is a predictor for obesity -- even stress and hopelessness could be factors. Overall, it comes down to food options: Poverty not only limits choices, but also can discourage healthy decisions that have little to do with money, they say.
For starters, the low-income tend to live in neighborhoods that are flush with fast-food restaurants and convenience stores that sell mostly junk foods, the experts say. Supermarkets are few -- and the fresh fruits, vegetables and lean meats they carry are more expensive than hamburgers, french fries and sodas.
The low-income "are buying what's available to them and affordable to them," said Genoveva Islas-Hooker, regional program coordinator for the Central California Regional Obesity Prevention Program.
People still are responsible for making the healthiest food choices possible, she said. But there, too, poverty's powers are hard to ignore.
Habits start young
Food habits begin in childhood, Islas-Hooker said. "You grow up in a household where there is limited economic means and your caregiver is purchasing food on what they can afford," she said. "You become ingrained in that type of diet and that type of pattern."
Carmen Solorvano, 30, of southeast Fresno grew up in a big family. There wasn't a lot of money for fresh fruits and vegetables and lean cuts of meat. Meals were mostly spaghetti, tacos, rice, beans, potatoes -- starchy foods.
Solorvano cooks those same foods today. "I'm used to cooking and eating the way I was raised, when I was small," she said.
She would like to fix healthier meals. She is 100 pounds overweight and her doctor has warned her she needs to lose weight. But money for healthy foods and time to prepare them are hard to come by.
Solorvano is a part-time food-service assistant. Her husband works part time at odd jobs. The family's combined income is about $900 a month, and they receive food stamps. Solorvano attends classes at Fresno City College in child development. She wants to become an assistant Head Start teacher. By the time she rushes home from picking her children up from school, she has to leave for class.
Meals have to be quick -- and cheap, she said.
Fatty, salty and sweet
Foods high in fat and carbohydrates and those full of sugar are cheap, energy-dense, nutrient poor -- and filling, said Edie Jessup, a program development specialist who works with Islas-Hooker at the obesity-prevention project.
Giving children a package of Top Ramen is an inexpensive, quick meal, Jessup said. "And because it's more carbohydrates, it makes your child feel like they've had more," she said.
Fats and sugars make foods taste good, too. "We really like fat, salty and sweet," Jessup said.
Some even suspect the foods are addictive.
A number of studies are looking at the physical response to such foods, according to the California Department of Public Health. The department says introducing fats and sugars to children early isn't recommended by pediatricians. They suggest giving infants pureed vegetables before pureed fruits so they can develop a taste for the vegetables and not reject them in favor of the sweeter fruit tastes, the department says.
Researchers who study the relationship between income and poverty speculate that some of the food choices made by the poor are not strictly cost-driven.
When you're living paycheck-to-paycheck, making a healthy food choice "is just not the highest priority in life," said Paul Leigh, an expert on health and labor economics and a professor at the Center for Healthcare Policy and Research at the University of California at Davis.
Leigh is senior author of a new study that found minimum-wage workers are more likely to be obese than people who earn higher wages.
People who live on minimum wages have fewer options than higher-wage earners, Leigh said.
"There is a direct causal relationship between the wages low-income people receive and their risk of obesity," he said.
But there also is an indirect emotional reaction. Living in poverty also involves stress, Leigh said. "With a certain amount of stress and unhappiness, you want to have some quick reward," he said. A sugary soda, for example, can provide a cheap, quick emotional lift.
The fast-food solution
By the same token, fast-food restaurants provide an outlet for low-income families: The food is cheap, it tastes good, and there is free entertainment for the children.
"The kids love it," Leigh said.
People with higher incomes can be selective about restaurants, he said.
Solorvano, the southeast Fresno mother, considers it a treat to take her children -- ages 14, 8 and 6 -- to McDonald's. The children look forward to it, she said. "They see other people and they go to McDonald's," she said. "They want to fit in."
Islas-Hooker understands the draw to fast food. The restaurants are hard to ignore when they're on every corner, a grocery store is several miles away and children are hungry.
And the Valley's immigrant population see images on television of happy people eating hamburgers and fries and drinking sodas, she said. "There's the psychology of the new immigrants wanting to fit in, and part of how they fit in to the new American society is adopting the diet."
In some cases, eating out or serving processed foods may be the only option for a family. The stove in the apartment may not work, they don't have pots and pans to use. They don't know how to cook.
"Half of the story is about people making smarter decisions," Islas-Hooker said. "But make sure healthy options are there."
The obesity epidemic among the poor has very little to do with individual motivation or even genetics or metabolism, said Dr. Adam Drewnowski, director of the Center for Public Health Nutrition at the University of Washington. He has specialized in the relationship between poverty and obesity for the past decade.
"Obesity is an expression of limited resources," he said. "Solutions really lie in education, instruction, access to healthy foods and being able to afford healthy foods."