The idea of food as medicine dates back to the ancient Greek doctor Hippocrates, and a new study adds to the evidence that a diet full of fruits and vegetables can help improve heart health. The research comes amid an epidemic of diet-related disease, which competes with smoking as a leading cause of death.

Researchers evaluated the impact of "produce prescriptions," which provide free fruits and vegetables to people with diet related diseases including diabetes, obesity and hypertension. The study included nearly 4,000 people in 12 states who struggle to afford healthy food. They received vouchers, averaging $63 a month, for up to 10 months, which could be redeemed for produce at retail stores or farmers markets, depending on the location.

Health care providers tracked changes in weight, blood pressure and blood sugar among the participants. "We were excited to see improvements," says study author Kurt Hager, an instructor at UMass Chan Medical School.

"Among adults with hypertension, we saw that systolic blood pressure decreased by 8 mm Hg and diastolic blood pressure decreased by about 5 mm Hg, which could have a meaningful impact on health outcomes," Hager says.

Among people with uncontrolled diabetes, their A1C levels, which is a 2-3 month average of their blood sugar, also declined significantly, by about .6 percent. "The reductions we saw in blood sugar were roughly half of that of commonly prescribed medications, which is really encouraging for just a simple change in diet," Hager says.

"I felt great," says Joann Erickson, 60, who participated in a produce prescription program at One Community Health in Sacramento, Calif. The program was organized by Wholesome Wave, a non-profit organization, at the forefront of initiatives aimed at making healthy food more affordable and accessible. Approximately 94% of the participants reported that taking part in the program improved their health.

"As a chef and father of two sons living with diabetes, I'm not surprised," says Wholesome Wave's co-founder Michel Nischan. "Our food strategy included increasing Chris and Ethan's consumption of fruits and vegetables significantly," he says, noting that his sons' A-1C went down and their insulin usage reduced as a result. "We knew we needed evidence to argue for policy change," he says.

"Being able to buy healthy food, I felt like a millionaire," Erickson says. She loaded her cart with strawberries, blueberries, cherries and salad greens, items she normally can't afford. "It was a big high for me," she says. After six months on the program her doctor was able to lower her blood pressure medication. Her blood sugar levels dropped, too. "I had more energy," Erickson says.

"Anything that lowers hemoglobin A1C and improves blood pressure control is beneficial," says Dr. Dariush Mozaffarian, a cardiologist and professor at the Friedman School of Nutrition at Tufts University, where the research was conducted. The challenge is to maintain these reductions. "Improvements in blood glucose can significantly reduce the risk of conditions like eye disease, kidney disease, and nerve disease," he says, which happen frequently among people with uncontrolled diabetes.

A year ago, following a White House conference on hunger, nutrition and health, the Biden administration announced a national strategy aimed at improving healthy eating and incorporating nutrition into health care. This created momentum to shore up the evidence as more healthcare providers connect the dots between diet and disease. "I think our study really provides a strong rationale for the next step of investment," says Hager. It's time to expand beyond pilot programs, "to further invest in larger trials with comparison groups," Hager says.

As the evidence continues to build, "it's important that we are simultaneously investing in the infrastructure needed to bring food is medicine prescriptions to scale," says Holly Freishtat, director of the Feeding Change initiative at the Milken Institute. Her team has outlined market solutions that could help support implementation, such as technology-enabled systems that would help patients to participate in food assistance programs, including SNAP (food stamps) and these newer approaches.

"With the increasing burden of chronic diet-related disease in the U.S., we can't afford [to] delay," Freishtat says. "We must find a way to make it easier for individuals to know their benefit eligibility, track their benefit amount status, and understand where and how to utilize those benefits," Freishtat says.

For now, the produce prescription programs offer only short-term assistance. Since Joann Erickson's produce vouchers ended, her monthly SNAP benefits were also cut significantly. Now, once again, she can't afford healthy food. "After I stopped the program, I saw my blood pressure going up," she says. "I would say there's a direct correlation," Erickson says.

For the food is medicine strategy to work, it's clear that the people will need long-term support.

"We need to get to a place where these are persistent benefits," says Mozaffarian. "If you get put on a blood pressure lowering medication, you're not going to go off the medication in six months," he says. The same is true if healthy food is prescribed. He says more research is needed to establish which patients benefit from which food assistance programs, whether it's medically-tailored meals or produce prescriptions, and what's the right amount they need to manage their conditions. But he says the ultimate goal is to get to a place where these are covered benefits for people who need them.

This story was edited by Jane Greenhalgh

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