Summary: Following a Mediterranean diet reduces the risk of all-cause mortality by 23 percent in American women over age 25. Nutritional benefits include lower cancer and cardiovascular mortality, positive changes in metabolism, inflammation and insulin resistance. Researchers analyzed biomarkers to understand these health improvements. The study highlights the diet’s potential for long-term health benefits.
Key Facts:
- A Mediterranean diet reduces the risk of all-cause mortality by 23% in American women.
- The benefits include lower cancer and cardiovascular mortality.
- Positive changes in metabolism, inflammation and insulin resistance explain the improvement in health.
Source: Brigham and Women’s Hospital
The health benefits of the Mediterranean diet have been reported in many studies, but long-term data on its effects on US women are limited and little is known about why the diet reduces the risk of death.
In a new study of more than 25,000 initially healthy American women up to age 25, researchers at Brigham and Women’s Hospital, a founding member of the Mass General Brigham Health Care System, found that participants who had a high Mediterranean diet were up to 23. The overall mortality risk % for cancer death and cardiovascular death benefit is lower.
The researchers found evidence of biological changes that could help explain why: they found changes in biomarkers such as metabolism, inflammation, insulin resistance, and more.
Results are published by Jama.
“For women who want to live longer, watch your diet! The good news is that following a Mediterranean diet cuts the risk of death over 25 years by nearly a quarter, with benefits from cancer and cardiovascular death for women (and men) in the US.” It is the leading cause of death worldwide,” said senior author Samia Mora, MD, cardiologist and director of the Lipid Metabolomics Center at Brigham.
The Mediterranean diet is a varied, plant-based diet rich in plants (nuts, seeds, fruits, vegetables, whole grains, legumes). The main fat is olive oil (usually virgin) and the diet also includes moderate amounts of fish, poultry, dairy, eggs and alcohol consumption and occasional consumption of meat, sweets and processed foods.
The current study examined the long-term benefits of following a Mediterranean diet in a US population recruited as part of the Women’s Health Study and examined the biological mechanisms that may explain the health benefits of the diet. The study investigators evaluated a panel of approximately 40 biomarkers representing different biological pathways and clinical risk factors.
Biomarkers metabolism and inflammation contributed the most, followed by triglyceride-rich lipoproteins, adiposity, and insulin resistance. Other biological pathways are related to branched-chain amino acids, high-density lipoproteins, low-density lipoproteins, glycemic parameters, and blood pressure.
“Our study provides important public health insights: even modest changes in risk factors for metabolic diseases—especially small molecule metabolites, inflammation, triglyceride-rich lipoproteins, obesity, and insulin resistance—result in significant long-term benefits from following a Mediterranean diet.”
“This finding highlights the potential of promoting healthy eating habits,” said lead author Shafkat Ahmed, PhD, associate professor of epidemiology and researcher in the Department of Lipid Metabolomics and Lipid Metabolomics at Uppsala University, Sweden. Preventive Medicine in Brigham.
The current study identifies important biological pathways that help explain the risk of all-cause mortality. However, the authors noted some key limitations, including that the study was limited to middle-aged and older well-educated female health professionals, who were typically non-Hispanic and white.
The study relied on food frequency questionnaires and other self-reported measures such as height, weight and blood pressure. However, the study’s strengths include a large and long follow-up period.
The authors note that as the concept of the Mediterranean diet has gained popularity, the diet has been adapted in different countries and cultures.
“The health benefits of the Mediterranean diet are recognized by medical professionals, and our study provides insights into why the diet is beneficial. Public health policies should promote the healthy eating habits of the Mediterranean diet and discourage unhealthy adaptations,” Mora said.
Authorship: In addition to Ahmed and Mora, Brigham authors include M. Vinayaga Moorthy, I-Min Lee, Paul M. Ridker, JoAnn E. Manson, Julie E. Buring, and Olga V. Demler.
Descriptions: Mora has reported on a patent application to assess glycoprotein acetylation in relation to colorectal cancer risk licensed to Labcorp and a patent application to predict future cardiovascular disease risk using an IgG glycome assay assigned to Genes Du and Brigham and Women’s Hospital. , Inc. More details can be found in the paper.
Financial support The Women’s Health Study is supported by the NIH (grant numbers CA047988, HL043851, HL080467, HL099355, and UM1 CA182913). Dr. Ahmed is supported by research grants from the Swedish Research Council (2022-01460) and FORMAS (2020-00989), as well as from EpiHealth, Sweden. Dr. Demler was supported by an award to K from the NHLBI of NIH Award No. K01HL135342-02.
Dr. Mora was supported by research grants from the National Institute of Diabetes and Digestive and Kidney Diseases (grant number DK112940); NHLBI (grant numbers R01HL160799, R01HL134811, R01HL117861 and K24 HL136852); American Heart Association (Grant No. 0670007N); and the Molino Family Trust.
In addition, LabCorp provided the LipoProfile IV results for the study at no additional cost.
So nutrition and mortality research news
Author: Cassandra Fallon
Source: Brigham and Women’s Hospital
Contact: Cassandra Fallon – Brigham and Women’s Hospital
Image: Image credited to Neuroscience News.
Preliminary study: Open Access.
“Adherence to the Mediterranean diet and risk of all-cause mortality in women“In Samia Mora et al. Jama Open the network
Draft
Adherence to the Mediterranean diet and risk of all-cause mortality in women
Importance
Adherence to the Mediterranean diet is associated with a reduced risk of all-cause mortality, but data on molecular mechanisms with long-term follow-up are limited.
Objectives
To examine adherence to the Mediterranean diet and the relative contribution of all-cause mortality and cardiometabolic factors to this risk reduction.
Design, composition and participants
This study included initially healthy women from the Women’s Health Study who provided blood samples, biomarker measurements, and dietary information. Baseline data included self-reported demographics and a validated food-frequency questionnaire. The data collection period was from April 1993 to January 1996 and data analysis was conducted from June 2018 to November 2023.
Exposure
A Mediterranean diet score (range, 0–9) was calculated based on 9 dietary components.
Main results and measurements
Thirty-three blood biomarkers, including traditional and novel lipid, lipoprotein, apolipoprotein, inflammatory, insulin resistance, and metabolic parameters, were assessed at baseline using standardized tests and nuclear magnetic resonance spectroscopy.
Mortality and cause of death were determined from medical and death records. Cox proportional hazards regression was used to calculate hazard ratios (HRs) for adherence to the Mediterranean diet and mortality, and mediation analyzes were used to calculate the median effect of different biomarkers to understand this association.
Results
Among 25 315 participants, the mean (SD) age at baseline was 54.6 (7.1) years, with 329 (1.3%) Asian women, 406 (1.6%) black women, 240 (0.9%) Hispanic women, and 24 036 (94.9%) white. women and 95 (0.4%) women with other race and ethnicity; The median (IQR) adherence score for the Mediterranean diet was 4.0 (3.0–5.0).
Over a mean (SD) of 24.7 (4.8) years of follow-up, 3879 people died. Compared with low Mediterranean diet (score 0–3), adjusted risk reductions for moderate (score 4–5) and high (score 6–9) groups, HRs 0.84 (95% CI, 0.78–0.90) and 0.77 (95% CI, 0.70–0.84), respectively (P for trend < .001).
Additional adjustment for lifestyle factors exacerbated the risk reductions, but they remained statistically significant (median adherence group: HR, 0.92 [95% CI, 0.85-0.99]; Upper compliance group: HR, 0.89 [95% CI, 0.82-0.98]; P for trend = .001). Among the investigated biomarkers, small molecule metabolites and inflammatory biomarkers contributed to the lowest risk of death (14.8% and 13.0% explaining the association, respectively), followed by triglyceride-rich lipoproteins (10.2%), body mass index (10.2%). ), and insulin resistance (7.4%).
Other pathways including branched-chain amino acids, high-density lipoproteins, low-density lipoproteins, glycemic parameters, and blood pressure had smaller contributions (<3%).
Conclusions and relevance
In this cohort study, adherence to the Mediterranean diet was associated with a 23 percent lower risk of death from all causes. This inverse association is partly explained by several cardiometabolic factors.