When you think about a healthy diet, do you consider the role the foods you eat play in reducing your risk of disease, their impact on the environment, or both? A new study found that choosing a diet that’s good for you and the planet is easier than you think — and could add years to your life.
The study, published in the journal Nature Food, evaluated over 5,800 foods based on their nutritional burden on global disease and their impact on the planet. It then broke down these foods into three zones defined by how many minutes of health were gained (or lost) as a result of including them in your diet, as well as the impact to the environment. For example, the analysis showed that a hog could cost you 36 minutes of your life, while a serving of nuts bought you time.
- Red zone: Foods in the red zone have little nutritional value and a negative impact on the environment. Processed meats and sugar sweetened beverages drove the most adverse health impact, while red meat, such as beef, pork and lamb, and processed meat had the greatest adverse impact to climate change due to increases to greenhouse gas emissions. In addition to meat, cheese-based foods and some salmon dishes were also identified as offenders to the environment. The authors of the study advised people to limit foods in the red zone.
- Yellow zone: Foods in this zone have slight adverse health impact and moderate impact to the environment. These include most poultry, dairy, egg-based foods, cooked grains such as rice and vegetables produced in a heated greenhouse. These foods should be eaten in moderation.
- Green zone: Foods in the green zone had high nutritional value and low environmental impact. They include nuts, fruits and vegetables (especially those grown in fields), legumes, whole grains and some seafood such as catfish (considered to have a low impact on the environment). The study authors concluded that these are the foods you should focus most on including in your diet.
In addition to keeping these zones in mind, here are three other takeaways from the study that you can use to guide your food choices.
Some healthy foods may have adverse impact on the environment
Numerous studies have demonstrated that consuming a plant-based diet can have a positive impact on physical and mental health. When it comes to the environmental impact however, it varies. For example, the researchers found that plants grown in fields are far better for the environment than plants grown in heated greenhouses. Another example is fatty fish. Though the data would clearly align fatty fish consumption with reduced risk of certain chronic diseases (due to their omega-3 content), the environmental impact varies greatly. The point here is not to skip these foods entirely, but instead, to be aware of their impact on climate change and adjust other parts of your diet to accommodate them.
Small changes can lead to big health benefits
A 10% adjustment in calories resulted in 48 minutes gained per day and reduction of your carbon footprint by one-third.
The study found that making small adjustments to the foods you eat can lead to a longer life and a healthier planet. In fact, making just a 10% adjustment in calories resulted in 48 minutes gained per day and reduction of your carbon footprint by one-third. This benefit was seen when red zone foods like beef and processed meat were replaced with fruit, vegetables, nuts, legumes and certain seafood.
The good news is it doesn’t take much to make a big impact. If you can’t keep all your dietary needs within the green zone, then simply substituting with some foods in the yellow zone can be beneficial as well. The point is, you can look at these zones in ways you may not have looked at dietary decisions before — simply choose the most from green, the least from red, and throw in some yellow every so often.
Knowing where your food comes from is critical
When my patients ask me where to get their eggs, I often tell them to find someone near their home who has chickens. I suggest visiting the operation to see firsthand how the chickens live and eat. The supply chain from the farm (or factory) to our plate is often not considered, but from a health and environment component, it’s critical.
You can consume healthier foods and limit your carbon footprint by growing your own crops and utilizing as little water as possible to do so. In fact, a key component in the study is how water utilization impacts the environment. If you buy your produce, then choose from field grown options and limit produce that has to travel more than 50 miles to reach your grocery store.
Determining a diet solution that works for you requires balancing the impact on your health with the impact on the earth. Researchers suggested that to do so you may have to make trade offs (such as having sustainable seafood over beef, for example), but doing so may help both you, and the planet, last longer.