Monday, June 10, 2024

 

Planetary Health Diet associated with lower risk of premature death, lower environmental impact


HARVARD T.H. CHAN SCHOOL OF PUBLIC HEALTH




Key takeaways:

  • People whose diets most closely adhered to the Planetary Health Diet (PHD) had 30% lower risk of premature death compared to those with the lowest adherence.
  • Every major cause of death, including cancer, heart disease, and lung disease, was lower with greater adherence to this dietary pattern.
  • Diets adhering to the PHD pattern had substantially lower environmental impact, including 29% lower greenhouse gas emissions and 51% less land use. 

Boston, MA—People who eat a healthy, sustainable diet may substantially lower their risk of premature death in addition to their environmental impact, according to a new study led by Harvard T.H. Chan School of Public Health. It is the first large study to directly evaluate the impacts of adherence to recommendations in the landmark 2019 EAT-Lancet report. The researchers have named the dietary pattern outlined in the report—which emphasizes a variety of minimally processed plant foods but allows for modest consumption of meat and dairy foods—the Planetary Health Diet (PHD).

The study will be published online June 10 in The American Journal of Clinical Nutrition.

“Climate change has our planet on track for ecological disaster, and our food system plays a major role,” said corresponding author Walter Willett, professor of epidemiology and nutrition. “Shifting how we eat can help slow the process of climate change. And what’s healthiest for the planet is also healthiest for humans.”

While other studies have found that diets emphasizing plant-based foods over animal-sourced foods could have benefits for human and planetary health, most have used one-time dietary assessments, which produce weaker results than looking at diets over a long period of time.

The researchers used health data from more than 200,000 women and men enrolled in the Nurses’ Health Study I and II and the Health Professionals Follow-Up Study. Participants were free of major chronic diseases at the start of the study and completed dietary questionnaires every four years for up to 34 years. Participants’ diets were scored based on intake of 15 food groups—including whole grains, vegetables, poultry, and nuts—to quantify adherence to the PHD. 

The study found that the risk of premature death was 30% lower in the top 10% of participants most closely adhering to PHD compared to those in the lowest 10%. Every major cause of death, including cancer, heart disease, and lung disease, was lower with greater adherence to this dietary pattern.

In addition, the researchers found that those with the highest adherence to the PHD had a substantially lower environmental impact than those with the lowest adherence, including 29% lower greenhouse gas emissions, 21% lower fertilizer needs, and 51% lower cropland use. 

The researchers noted that land use reduction is particularly important as a facilitator of re-forestation, which is seen as an effective way to further reduce levels of greenhouse gases that are driving climate change.  

“Our study is noteworthy given that the U.S. Department of Agriculture has refused to consider the environmental impacts of dietary choices, and any reference to the environmental effects of diet will not be allowed in the upcoming revision of the U.S. Dietary Guidelines,” said Willett. “The findings show just how linked human and planetary health are. Eating healthfully boosts environmental sustainability—which in turn is essential for the health and wellbeing of every person on earth.”

Other Harvard Chan School authors included Linh Bui, Fenglei Wang, Qi Sun, Frank Hu, Kyu Ha Lee, and Marta Guasch-Ferre.

The study was funded by National Institutes of Health (NIH) research grants UM1 CA186107, P01 CA87969, R01 HL034594, U01 CA176726, U01 CA167552, R01 HL035464, R01 DK120870, and R01 DK126698.

“Planetary Health Diet Index and risk of total and cause specific mortality in three prospective cohorts,” Linh P. Bui, Tung T. Pham, Fenglei Wang, Boyang Chai, Qi Sun, Frank B. Hu, Kyu Ha Lee, Marta Guasch-Ferre, Walter C. Willett, The American Journal of Clinical Nutrition, June 10, 2024, doi: 10.1016/j.ajcnut.2024.03.019

Visit the Harvard Chan School website for the latest newspress releases, and multimedia offerings.

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Harvard T.H. Chan School of Public Health brings together dedicated experts from many disciplines to educate new generations of global health leaders and produce powerful ideas that improve the lives and health of people everywhere. As a community of leading scientists, educators, and students, we work together to take innovative ideas from the laboratory to people’s lives—not only making scientific breakthroughs, but also working to change individual behaviors, public policies, and health care practices. Each year, more than 400 faculty members at Harvard Chan School teach 1,000-plus full-time students from around the world and train thousands more through online and executive education courses. Founded in 1913 as the Harvard-MIT School of Health Officers, the School is recognized as America’s oldest professional training program in public health.

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Alarming trends call for action to define the future role of food in nation’s health



New public opinion poll and expert analysis reflect crucial need to make healthy food accessible to avert projected crisis in cardiovascular disease incidence, costs


AMERICAN HEART ASSOCIATION





CHICAGO, June 10, 2024 — The cost of nutritious food and the lack of access to it are of significant concern to U.S. consumers. That’s according to a new national poll of public attitudes on food and nutrition conducted by Zogby Analytics on behalf of Research!America and the American Heart Association. Nearly 7 in 10 (68%) respondents recognize healthy eating habits as an important factor in improving a person’s chance for a long and healthy life. Yet more than half (53%) say the United States is not making enough progress for nutritious food to be more accessible and affordable.

The polling results are included in an expert analysis of U.S. health and the future of food that outlines steep challenges to improving nutrition security, caused by systemic factors that can make it more difficult for people to access healthy food. The report, released today by Deloitte, the American Heart Association and Research!America, details the urgent challenges to creating a food system that effectively integrates nutritious food into health care for the prevention, treatment and care of cardiovascular disease and other chronic conditions.

These findings were announced at The Drake Hotel in Chicago, the birthplace exactly 100 years ago of the American Heart Association, the world’s leading public health  organization focused on heart and brain health for all.

“Efforts led by the American Heart Association have cut death rates from heart disease by half in the past 100 years, but as we look to our second century of existence, the trends are ominous,” said Nancy Brown, chief executive officer of the American Heart Association. “We are committed to averting a crisis of unparalleled health and economic burdens due to cardiovascular disease and obesity in the coming decades.”

According to stark projections published June 4 in the Association’s flagship peer-reviewed journal Circulation, obesity, if left unaddressed, will be a significant driver of sharp increases in cardiovascular disease that are anticipated by 2050:

  • More than 6 in 10 (61%) U.S. adults are projected to have some form of cardiovascular disease by 2050 – up from about half of all adults currently.
  • Obesity rates will increase nearly 40% in adults. from 43.6% to 60.6%, and by more than 60% in children, from 20.6% to 33% by 2050.
  • The highest growth of obesity prevalence is expected to be among adults 20-44 and 45-64 years old. In children, a steep growth of obesity is projected in all age groups.
  • More than 150 million people (close to half of the nation’s population) will have a poor diet – the most prevalent factor affecting health conditions such as hypertension, obesity and diabetes.

Obesity is also a major factor in the public’s perceptions of health in the U.S., according to the public opinion survey. A resounding 94% of respondents believe that obesity is either a somewhat (41%) or very (53%) serious concern.

More than 3 in 4 respondents (77%) said they would like to eat a healthier diet. However, respondents reported significant barriers to achieving that, including:

  • The cost of healthy food (60%): Many find it challenging to afford nutritious options.
  • Stress eating (42%): Emotional factors play a role in dietary choices.
  • Lack of preparation time (33%): Busy schedules hinder meal preparation.
  • Lack of knowledge (32%): Understanding what foods are healthy and how to prepare them remains a challenge.

“The results show significant differences in how historically underrepresented groups rank the barriers to healthy eating,” said Mary Woolley, president and CEO of Research!America, a nonprofit medical and research advocacy alliance. “Nearly 7 in 10 Asian American (66%) and Hispanic (68%) respondents said the cost of healthy food was their biggest barrier to healthy eating. Black respondents were more likely to cite gaps in knowledge about healthy food (38%) and difficulty accessing stores that carry a selection of nutrient-dense foods (25%) as barriers to healthy eating.”

The U.S. Health and the Future of Food report implicates food and nutrition insecurity (the inability to attain adequate calories and nutrition to support health), ultra-processed foods and the lack of resilient and adaptive food and agricultural systems as major contributors to poor diets. As cited in the report, approximately 1 in 7 people in the U.S. faced food insecurity in 2022 – a total of 44 million people, including 13 million children, marking the highest rates since 2014.

“The impact of food insecurity is felt disproportionately in rural (90%) and southern (80%) U.S. counties, but food and nutrition insecurity exist across the U.S.,” said James Cascone, partner, Deloitte Sustainability, Climate & Equity strategic growth offering and the Future of Food leader for the Americas. “Factors including consumer preferences, cultural norms and unhealthy food marketing, compounded by social inequities and food and nutrition insecurity, impede access to healthy foods. The resulting decline in diet quality significantly raises the risk of chronic conditions including cardiovascular disease.”

Nearly 60% of the U.S. diet is comprised of ultra-processed foods that are high in refined grains, calories, sodium, sugar and saturated fat, and are more often selected by consumers over nutritionally healthier alternatives, according to statistics cited in the report. The report calls for stakeholders including health care professionals, food industries, policymakers and others to drive innovations that enable food systems to bolster health outcomes.

“Healthy, nutritious food not only leads to better overall health – it can be a critical tool to treat, manage and prevent chronic disease,” said Kevin Volpp, M.D., Ph.D., American Heart Association volunteer, scientific lead for the Association’s food is medicine initiative Health Care by Food™ and founding director of the Center for Health Incentives and Behavioral Economics at the University of Pennsylvania’s Perelman School of Medicine and the Wharton School. “Cross-sector collaboration and research-backed innovation in public and private sector programs are needed to stem the combined tidal wave of obesity and nutrition insecurity, threatening the health of millions of people in the U.S. now and for decades to come.”

The Association’s Health Care by Food™ initiative is investing in research, advocacy and education to integrate cost-effective food is medicine approaches into the health care system. Initial pilot studies funded by the Association are underway to help strengthen the evidence base by demonstrating the effectiveness of healthy food interventions applied within the health care system.

The Association also is driving greater understanding of the components of specific foods and their role in human health in collaboration with the Periodic Table of Food Initiative (PTFI). PTFI was established by multiple academic disciplines along with the technology, philanthropy and nonprofit sectors five years ago to better understand food biodiversity by building a unique database of the global food supply to inform dietary recommendations and agricultural practices to enhance both human and planetary health.

Brown noted that additional health and nutrition solutions are needed to prevent projected increases in cardiovascular disease incidence and cost.

“We must make bold moves to change the troubling trajectory of cardiovascular disease. That is why the American Heart Association will soon launch a novel, longitudinal direct-to-patient registry of individuals living with overweight and obesity and those prescribed treatment for weight management,” Brown said. “Building on our decades of experience in patient registries and inspired by the Framingham Heart Study, this groundbreaking registry will provide seminal research to improve understanding of the causes and treatments for obesity, and how obesity is managed by health care professionals.”

The new initiative will help set the stage for fundamentally shaping public health guidelines related to nutrition and obesity. Brown called on others to embrace these types of innovative and comprehensive approaches to improving the nation’s health.

“Collaborative efforts from public and private entities are imperative to advance health and nutrition approaches that could shape the course of public health in the next century,” Brown said. “We invite stakeholders from across the health and nutrition sectors to join us in this fight to ensure that every person has access to nutritious food that leads to better health.”   

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About the American Heart Association 

The American Heart Association is a relentless force for a world of longer, healthier lives. We are dedicated to ensuring equitable health in all communities. Through collaboration with numerous organizations, and powered by millions of volunteers, we fund innovative research, advocate for the public’s health and share lifesaving resources. The Dallas-based organization has been a leading source of health information for a century. During 2024 - our Centennial year - we celebrate our rich 100-year history and accomplishments. As we forge ahead into our second century of bold discovery and impact our vision is to advance health and hope for everyone, everywhere. Connect with us on heart.orgFacebookX or by calling 1-800-AHA-USA1.    

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