Researchers studied whether eating a diet that’s good for the environment is also good for your health. They looked at data from thousands of older adults and found that people who followed a “planetary health diet”—which focuses on plant-based foods, whole grains, and less meat—had lower risks of dying from heart disease and other causes. This diet is designed to be healthy for both people and the Earth. The findings suggest that choosing foods that help our planet might also be one of the best things you can do for your own health.
The Quick Take
- What they studied: Whether eating a diet that’s environmentally friendly (the planetary health diet) helps people live longer and reduces heart disease risk
- Who participated: Older adults (average age 65+) from the Health and Retirement Study, a long-running research project tracking American adults over time
- Key finding: People who most closely followed the planetary health diet had significantly lower risks of dying from any cause and from heart disease specifically, compared to those who followed it least
- What it means for you: Choosing more plant-based foods, whole grains, nuts, and less red meat might help you live longer and protect your heart. However, this is one study, so talk to your doctor about dietary changes that work best for you personally
The Research Details
This was a cohort study, which means researchers followed a large group of people over many years and tracked what they ate and what happened to their health. The researchers looked at data from the Health and Retirement Study, which has been following American adults since 1992. They created a scoring system to measure how closely each person followed the planetary health diet—a way of eating that emphasizes vegetables, fruits, whole grains, legumes, nuts, and fish while limiting red meat, processed foods, and added sugars. They then compared health outcomes between people with high scores (eating this way most) and low scores (eating this way least).
The researchers tracked participants for about 10 years and recorded who developed heart disease, who had heart attacks or strokes, and who died. They adjusted their analysis to account for other factors that affect health, like smoking, exercise, and overall health status, so they could focus on the diet’s specific effects.
This approach is valuable because it shows real-world eating patterns and long-term health outcomes in actual people, rather than just testing diet in a lab setting.
Following people over many years in their real lives gives us practical information about whether dietary changes actually work in the long term. This study design is particularly useful for understanding how diet affects serious health outcomes like heart disease and death, which take years to develop.
This study has several strengths: it followed a large number of people over a long period, it measured actual food intake, and it accounted for many other health factors. However, the study relied on people remembering what they ate, which can be imperfect. Also, people who choose to eat this way might differ in other healthy habits, making it hard to know if the diet itself or other lifestyle choices caused the benefits.
What the Results Show
People who followed the planetary health diet most closely had about a 30% lower risk of dying from any cause during the study period compared to those who followed it least. They also had significantly lower risks of dying specifically from heart disease. These benefits were seen even after researchers accounted for other important health factors like age, smoking, exercise, and body weight.
The benefits appeared to increase gradually—people who followed the diet moderately well had moderate benefits, while those who followed it most closely had the greatest protection. This suggests that the more closely you follow this eating pattern, the more benefit you might receive.
The protective effects were consistent across different age groups and between men and women, suggesting this diet may help many different types of people.
The study also found that people following the planetary health diet had lower rates of heart attacks and strokes, though the protection was somewhat less dramatic than for overall mortality. The diet appeared particularly protective for people over age 75. Additionally, the benefits were seen in people across different income and education levels, suggesting this isn’t just a diet for wealthy or highly educated people.
These findings align with previous research showing that plant-based and Mediterranean-style diets reduce heart disease risk. However, this study is unique because it specifically examined a diet designed to be sustainable for the planet while also being healthy for people. It adds to growing evidence that what’s good for the environment may also be good for human health.
The main limitation is that participants reported their own food intake, which may not be perfectly accurate. People who choose to eat this way might also exercise more, manage stress better, or have other healthy habits that contributed to their longevity—so we can’t be completely certain the diet alone caused the benefits. The study included mostly older American adults, so results might differ for younger people or in other countries with different food availability. Finally, this was an observational study, not a controlled experiment, so it shows association but not definitive cause-and-effect.
The Bottom Line
Consider gradually increasing plant-based foods (vegetables, fruits, whole grains, beans, nuts) and reducing red and processed meat in your diet. This appears to be a safe, evidence-based approach to eating that may reduce serious health risks. Confidence level: Moderate to High (based on consistent findings across multiple studies, though this is one new study). Start with small changes—try meatless Mondays, add beans to meals, or swap red meat for fish a few times per week.
This research is relevant for anyone interested in living longer and reducing heart disease risk, particularly adults over 50. It’s especially important for people with family histories of heart disease or those already diagnosed with heart conditions. People with certain medical conditions (like kidney disease or specific allergies) should consult their doctor before making major dietary changes. Younger people may also benefit, though this study focused on older adults.
Heart disease develops over years, so you shouldn’t expect immediate changes. However, some benefits like improved energy, better digestion, and weight loss might appear within weeks to months. Significant reductions in disease risk typically take 1-2 years of consistent dietary changes to become apparent.
Want to Apply This Research?
- Track daily servings of plant-based foods (vegetables, fruits, whole grains, legumes, nuts) and weekly servings of red meat. Aim to increase plant foods and decrease red meat over time. A simple goal: 5+ servings of vegetables and fruits daily, 3+ servings of whole grains, and red meat no more than 2-3 times per week.
- Start with one specific change: choose one meal per week to make plant-based, or replace one meat-based snack with nuts or seeds. Use the app to log this meal and track your progress. Gradually expand to more meals as the habit becomes comfortable.
- Weekly check-ins on plant-based meal frequency and red meat consumption. Monthly reviews of overall diet quality and how you’re feeling (energy levels, digestion, weight). Annual health metrics (blood pressure, cholesterol, weight) to track long-term health improvements.
This research suggests associations between diet and health outcomes but does not prove that dietary changes will prevent disease in all individuals. Results from this study may not apply to all populations, ages, or health conditions. Before making significant dietary changes, especially if you have existing health conditions, take medications, or have food allergies, consult with your healthcare provider or a registered dietitian. This information is for educational purposes and should not replace professional medical advice.