So far, not really
By PETER DIZIKES, MASSACHUSETTS
INSTITUTE OF TECHNOLOGY
How much can healthy eating improve a case of diabetes? A new healthcare program attempting to treat diabetes by means of improved nutrition shows a very modest impact, according to the first fully randomized clinical trial on the subject.
The study, co-authored by MIT health care economist Joseph Doyle of the MIT
Sloan School of Management, tracks participants in an innovative program that
provides healthy meals in order to address diabetes and food insecurity at the
same time. The experiment focused on Type 2 diabetes, the most common form.
Clinical Trial Findings and Implications
The program involved people with high blood sugar levels, in this case an HbA1c hemoglobin level of 8.0 or more. Participants in the clinical trial who were given food to make 10 nutritious meals per week saw their hemoglobin A1c levels fall by 1.5 percentage points over six months.
However, trial participants who were not given any food had
their HbA1c levels fall by 1.3 percentage points over the same time. This
suggests the program’s relative effects were limited and that providers need to
keep refining such interventions.
“We found that when people gained access to
[got food from] the program, their blood sugar did fall, but the control group
had an almost identical drop,” says Doyle, the Erwin H. Schell Professor of
Management at MIT Sloan.
Food Insecurity and Health Outcomes
Given that these kinds of efforts have barely
been studied through clinical trials, Doyle adds, he does not want one study to
be the last word, and hopes it spurs more research to find methods that will
have a large impact. Additionally, programs like this also help people who lack
access to healthy food in the first place by dealing with their food
insecurity.
“We do know that food insecurity is problematic for people, so addressing that by itself has its own benefits, but we still need to figure out how best to improve health at the same time if it is going to be addressed through the health care system,” Doyle adds.
Study Execution and Results
To conduct the study, the researchers
partnered with a large health care provider in the Mid-Atlantic region of the
U.S., which has developed food-as-medicine programs. Such programs have become
increasingly popular in health care, and could apply to treating diabetes,
which involves elevated blood sugar levels and can create serious or even fatal
complications. Diabetes affects about 10 percent of the adult population.
The study consisted of a randomized clinical trial of 465 adults with Type 2 diabetes, centered in two locations within the network of the health care provider. One location was part of an urban area, and the other was rural.
The study took place from 2019 through 2022, with a
year of follow-up testing beyond that. People in the study’s treatment group
were given food for 10 healthy meals per week for their families over a
six-month period, and had opportunities to consult with a nutritionist and
nurses as well. Participants from both the treatment and control groups
underwent periodic blood testing.
Analyzing the Program’s Effectiveness
Adherence to the program was very high.
Ultimately, however, the reduction in blood sugar levels experienced by people
in the treatment group was only marginally bigger than that of people in the
control group.
Those results leave Doyle and his co-authors
seeking to explain why the food intervention didn’t have a bigger relative
impact. In the first place, he notes, there could be some basic reversion to
the mean in play — some people in the control group with high blood sugar
levels were likely to improve that even without being enrolled in the program.
Future Directions and the Role of Meal Preparation
“If you examine people on a bad health
trajectory, many will naturally improve as they take steps to move away from
this danger zone, such as moderate changes in diet and exercise,” Doyle says.
Moreover, because the healthy eating program
was developed by a health care provider staying engaged with all the
participants, people in the control group may have still benefitted from
medical engagement and thus fared better than a control group without such
health care access.
It is also possible the COVID-19 pandemic, unfolding during the experiment’s
time frame, affected the outcomes in some way, although results were similar
when they examined outcomes prior to the pandemic. Or it could be that the
intervention’s effects might appear over a still-longer time frame.
And while the program provided food, it left
it to participants to prepare meals, which might be a hurdle for program
compliance. Potentially, premade meals might have a bigger impact.
“Experimenting with providing those premade
meals seems like a natural next step,” says Doyle, who emphasizes that he would
like to see more research about food-as-medicine programs aiming at diabetes,
especially if such programs evolve and try to some different formats and
features.
“When you find a particular intervention
doesn’t improve blood sugar, we don’t just say, we shouldn’t try at all,” Doyle
says. “Our study definitely raises questions, and gives us some new answers we
haven’t seen before.”
Research Methodology and Participant Demographics
The paper, “The Effect of an Intensive Food-as-Medicine Program on Health and Health Care Use: A Randomized Clinical Trial,” was published recently in JAMA Internal Medicine.
The authors are Doyle; Marcella Alsan, a professor of public policy at Harvard Kennedy School; Nicholas Skelley, a predoctoral research associate at MIT Sloan Health Systems Initiative; Yutong Lu, a predoctoral technical associate at MIT Sloan Health Systems Initiative; and John Cawley, a professor in the Department of Economics and the Department of Policy Analysis and Management at Cornell University and co-director of Cornell’s Institute on Health Economics, Health Behaviors and Disparities.
Reference: “Effect of an Intensive
Food-as-Medicine Program on Health and Health Care Use: A Randomized Clinical
Trial” by Joseph Doyle, Marcella Alsan, Nicholas Skelley, Yutong Lu and John
Cawley, 26 December 2023, JAMA Internal Medicine.
DOI:
10.1001/jamainternmed.2023.6670