ANN ARBOR, Mich. — Choose wisely. The next food choice you make may rob you of precious minutes of healthy living. University of Michigan researchers say eating a hot dog may shorten your “healthy life” by up to 36 minutes. On the other hand, eating a serving of cashews instead may extend it by 26 minutes!
Those are just some of the findings in a new study that concludes substituting just 10 percent of your usual daily caloric intake from beef and processed meats with a mixture of fruits, vegetables, nuts, legumes, and some seafoods may result in two major benefits. To start, your dietary carbon footprint will drop by a third. Secondly, you’ll extend your window of healthy living by an extra 48 minutes every single day!
When researchers talk about “healthy living,” the team says they’re referring to the ability to live life on one’s own terms — without having to deal with fragility, sickness, or disability. Study authors examined over 5,800 different foods during this project, ranking each according to both their nutritional disease burden on humans and environmental impact.
“Generally, dietary recommendations lack specific and actionable direction to motivate people to change their behavior, and rarely do dietary recommendations address environmental impacts,” says Katerina Stylianou, who performed this research as a doctoral candidate and postdoctoral fellow in the the Department of Environmental Health Sciences at U-M’s School of Public Health, in a university release.
Some foods get a ‘green light’ for health
These findings come from a new epidemiology-based nutritional index, the Health Nutritional Index (HENI), created by the research team behind this study. For a single serving of food, HENI calculates the associated net beneficial or detrimental health burden in minutes of healthy life. The Global Burden of Disease (GBD) also played heavily into this work, which is the theory that every single serving of food we eat has a connection to both disease mortality and morbidity.
While constructing the HENI, researchers used 15 dietary risk factors and disease burden estimates taken from the GBD. They combined them with the nutrition profiles of various foods commonly eaten in the United States, according to the What We Eat in America database of the National Health and Nutrition Examination Survey.
While that process sounds a bit complicated, it’s ultimate result is quite simple — foods with a positive score add healthy life minutes. Meanwhile, foods with a negative score lead to unhealthy outcomes.
The Michigan team also used another method to assess and rate the environmental impact of various foods across a number of considerations including production, processing, manufacturing, preparation and cooking, consumption, waste, and fine particulate matter formation. All of this data classified foods into three different color zones based on their combined environmental and nutritional profiles: green, yellow, and red.
Green zone foods both promote a healthier life and are good for the planet. These foods include nuts, fruits, field-grown vegetables, legumes, whole grains, and some forms of seafood. On the other end of the spectrum, red zone foods offer little nutritional or environmental benefits. This group includes highly processed meat, beef, shrimp, pork, lamb, and greenhouse-grown vegetables.
This doesn’t mean ‘avoid all meat’
While highly-processed meats are the worst from a health perspective, beef, pork, lamb, and processed meats all make major negative impacts from an environmental standpoint as well. However, study authors stress that these findings aren’t as black and white as “avoid meat, eat fruit.” Many foods that are great for us health-wise may not be great for the planet and vice versa.
“Previous studies have often reduced their findings to a plant vs. animal-based foods discussion,” Stylianou notes. “Although we find that plant-based foods generally perform better, there are considerable variations within both plant-based and animal-based foods.”
“The urgency of dietary changes to improve human health and the environment is clear,” concludes senior study author Olivier Jolliet, U-M professor of environmental health science. “Our findings demonstrate that small targeted substitutions offer a feasible and powerful strategy to achieve significant health and environmental benefits without requiring dramatic dietary shifts.”
The study is published in Nature Food.