Doctors should have confidence in recommending plant-based foods such as fruit, vegetables, legumes, and whole grains for managing and preventing major chronic diseases, says a meta-epidemiological study from the American College of Lifestyle Medicine (ACLM) that was recently published in the medical journal Advances in Nutrition.
The study reviewed 78 clinical practice guidelines published between 2010 and 2021 in North America, Europe, and Asia and found close alignment in their recommendations for encouraging daily consumption of plant-based foods, while limiting consumption of alcohol, salt, sodium, red meat, and processed meat.
What food groups are better for health?
In analyzing the specific food groups, the researchers found that nearly three quarters of clinical practice guidelines recommended including or increasing intake of vegetables, which was the highest percentage of any food group.
No guidelines recommended excluding or reducing vegetables. In addition to vegetables, fruit was the most commonly recommended food group at 69 percent, whole grains at 58 percent, and legumes at 47 percent.
The food groups most often recommended to limit or reduce among guideline recommendations were red meat at 32 percent, followed by processed meat at 27 percent, and refined grains at 19 percent.
Among food components, 62 percent of guidelines recommended excluding, decreasing or limiting alcohol, and 56 percent recommended the same of salt or sodium. The most recommended food components were vegetable oils at 35 percent and soy protein at 18 percent.
“These findings demonstrate that global dietary and nutrition guidelines support and are aligned with ACLM’s recommendation that, for the treatment, reversal, and prevention of lifestyle-related chronic disease, the optimal eating plan is predominantly based on a variety of minimally processed vegetables, fruits, whole grains, legumes, nuts and seeds,” Micaela Karlsen, PhD, MSPH, ACLM, Senior Director of Research and senior study author, said in a statement.
Nutrition for chronic disease
Clinical practice guidelines reviewed for this study were developed by governments, major medical professional societies, and large health stakeholder associations to improve the health of adults with chronic diseases, such as type 2 diabetes, cancer, cardiovascular disease, digestive diseases, weight-related conditions, and chronic obstructive pulmonary disease. Dietary patterns, food groups, and food components were of primary interest in the study, while macronutrient and micronutrient recommendations were a secondary interest.
The researchers focused on major guidelines for the study because that’s what doctors rely on for their everyday practice. “Clinicians depend on clinical practice guidelines developed from the most current and rigorous medical research to help steer their diagnoses, treatment, and management of common chronic diseases,” Beth Frates, MD, ACLM President and Clinical Assistant Professor at Harvard Medical School, said in a statement.
“The results of this comprehensive review of evidence-based clinical practice guidelines are important because they can benefit both clinicians and their patients by reducing the variability in dietary and nutrition guidance that often prevents clinicians from providing optimal care,” Frates said.
Why nutrition is so important
The study notes that the Global Burden of Disease Report has confirmed that an unhealthy diet is responsible for more deaths globally than any other risk factor, including tobacco smoking. To the authors’ knowledge, this was the first study to compare dietary recommendations across current clinical practice guidelines for multiple major chronic diseases.
According to the ACLM researchers, the study’s findings are important because patients have reported confusion caused by contradictory nutrition messaging, especially online. And, notably, physicians, whose expertise is frequently sought by patients, often receive insufficient nutrition education in medical school to feel confident giving dietary guidance to patients for the treatment of chronic disease.
“The growing prevalence of overweight [individuals] and obesity and the associated chronic conditions are a serious public health threat that must be urgently addressed,” Kelly C. Cara, MS, doctoral student at Tufts University Friedman School of Nutrition Science and Policy, the study’s first author, said in a statement.
“Patients look to healthcare professionals for dietary guidance, so it is critical that physicians are fully informed and confident when offering recommendations to patients in order to provide the best outcomes,” Cara said. “We hope the results of this study will assist physicians in developing the foundation of knowledge needed to achieve those outcomes.”