Small Food Swaps Can Extend Your Life and Benefit the Planet
- A new study in Nature Food creates a Health Nutritional Index (HENI), which rates more than 5 800 commonly consumed foods by the minutes of life lost or gained per serving eaten.
- For example, a handful of nuts prolongs your healthy life by 26 minutes, while a hotdog in a bun subtracts 36 minutes, according to the study.
- The study also rates the foods green, amber, or red, according to their environmental impact, with most plant foods ranking healthiest for the planet.
You do your best to make smart food choices for your own health and maybe even for the that of the environment, too. But how much of a difference does that fistful of nuts on your way to the gym or burger at the bar after a ride really make either way?
A new study in the research journal Nature Food has provided some of the first hard numbers for the health benefits (and burdens) of our food choices, both on their impact on our personal health and that of the environment.
The study’s main take home message: By substituting 10 percent of your daily caloric intake from beef and processed meats for a mix of fruits, vegetables, nuts, legumes, and select seafood, you can reduce your dietary carbon footprint by one-third and gain 48 minutes of “healthy life,” meaning good-quality, disease-free life, per day.
Yes, the study gets that specific. To arrive at those numbers, the researchers pulled data from the Global Burden of Disease (GBD), a comprehensive epidemiological study and database that includes 15 dietary risk factors contributing to health and/or disease and combined them with the nutrition profiles of more than 5,800 foods consumed in the United States, based on the What We Eat in America database of the National Health and Nutrition Examination Survey.
The estimated health benefits came from foods like milk, nuts and seeds, fruits, calcium, omega-3 fatty acids from seafood, fibres from fruits, vegetables, legumes, whole grains, and polyunsaturated fatty acids (PUFAs). Estimated health damages were associated with foods like processed meat, red meat, trans fatty acids, sugar-sweetened beverages, and sodium.
Researchers then scaled that data to standard serving sizes and created a Health Nutritional Index (HENI), which translated the information into minutes of life lost or gained per serving size of each food consumed. When foods are mixed into one dish (as they often are), the pluses and minuses are figured into the equation for the net gain or loss.
For instance, a handful of nuts prolongs your healthy life by 26 minutes, and a PB&J sandwich can score you an additional 33 minutes of healthy life (and help power you through your next century ride). Omega-3s and produce are so beneficial that sardines in tomato sauce will help you bank you an extra 82 minutes of healthy life.
Less healthful choices subtract minutes. For example, the study authors found that on average you lose 0.45 minutes per gram of processed meat. Foods with trans fatty acids and sodium—like a hotdog on a bun—can set you back 36 minutes, while a serving of chicken wings can dock you 3.3 minutes of healthy life.
It’s worth noting that while there’s definitely merit to these health findings, try not to obsess over the foods you consume. Though it’s important to be aware of the nutritional content of what you’re eating, being fixated on every last detail isn’t healthy and can take the fun out of fuelling your rides.
To determine the effect of food choices on the environment, researchers evaluated each food based on 18 environmental indicators, including carbon footprint, air pollution, and water use impacts. They coded each of the foods green (good for the environment), amber (slightly detrimental or generate moderate environmental impacts), or red (have either considerable negative nutritional or high environmental impacts), according to their impact on the planet.
Green zone foods are predominantly made from nuts, fruits, vegetables, legumes, whole grains, and some seafood. Amber zone foods include most poultry, dairy (milk and yogurt), egg-based foods, cooked grains, and vegetables produced in a greenhouse. Red zone foods include processed meat, sugar-sweetened beverages, beef, pork, and lamb.
“Previous studies have often reduced their findings to a plant- versus animal-based foods discussion,” said Katerina Stylianou, M.S., who did the research as a doctoral candidate and postdoctoral fellow in the Department of Environmental Health Sciences at the University of Michigan’s School of Public Health, in a press release. “Although we find that plant-based foods generally perform better, there are considerable variations within both plant-based and animal-based foods.”
Based on these findings, the researchers suggest:
- Decreasing foods with the most negative health and environmental impacts, including high processed meat, beef, and shrimp, followed by pork, lamb, and greenhouse-grown vegetables.
- Increasing the most nutritionally beneficial foods, including field-grown fruits and vegetables, legumes, nuts, and low-environmental impact seafood
“The urgency of dietary changes to improve human health and the environment is clear,” said Olivier Jolliet, Ph.D., professor of environmental health science at the University of Michigan and senior author of the paper, said in the press release. “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 project was carried out within the frame of an unrestricted grant from the National Dairy Council and of the University of Michigan Dow Sustainability Fellowship, but the researchers noted they were careful to not allow for bias.
“We have intentionally not deviated from the GBD choices to avoid biases [such as those] in favor of the dairy industry,” Jolliet told Bicycling.
We can expect that the HENI scores will evolve as research continues to be conducted on both the health and environmental impact of individual foods.