New Research Links Red Meat Consumption to a 22% Higher Risk of Heart Disease

The research additionally discovered that consuming fish, poultry, and eggs was not related to coronary heart illness.

Blood sugar, basic irritation, and microbiome-related metabolites like TMAO appear to be extra essential in regulating coronary heart illness threat than blood stress or levels of cholesterol.

Is there a hyperlink between consuming extra meat, significantly purple and processed meat, and an elevated threat of heart problems? If that’s the case, why? The results of meals derived from animals on atherosclerotic heart problems (ASCVD) are hotly contested regardless of intensive analysis, and the mechanisms behind any attainable impacts of animal proteins are nonetheless unknown. Understanding the results of meat consumption is essential for older adults since they’re most in danger for coronary heart illness and will profit from consuming protein to counteract the deterioration of muscle mass and power that comes with getting old.

The hyperlink between coronary heart illness and saturated fats, dietary ldl cholesterol, sodium, nitrites, and even high-temperature cooking has been studied by scientists through the years, however the proof for a lot of of those mechanisms has not been robust. Latest knowledge factors to particular metabolites produced by our intestine micro organism once we devour meat because the potential underlying culprits. 

A latest research headed by scientists on the Cleveland Clinic Lerner Analysis Institute and the Friedman College of Diet Science and Coverage at Tufts College quantifies the chance of ASCVD related to meat consumption and identifies underlying biologic pathways that will clarify this threat. The research of over 4,000 women and men over the age of 65 in the USA discovered that higher meat consumption is related to an elevated threat of ASCVD—22 % increased threat for each 1.1 serving per day—and that elevated ranges of three metabolites generated by intestine micro organism from vitamins prevalent in meat clarify roughly 10% of this elevated threat. Pink meat was related to the next threat and interconnections with intestine bacterial metabolites, nonetheless, this was not discovered for poultry, eggs, or fish. 

The analysis, which was just lately revealed within the journal Arteriosclerosis, Thrombosis, and Vascular Biology, is the primary to look at the connections between animal supply meals and the chance of ASCVD occasions, and the mediation of this threat by intestine microbiota-generated compounds in addition to by conventional ASCVD threat pathways similar to blood ldl cholesterol, blood stress, and blood sugar.

The analysis drew on years of information from the Nationwide Institutes of Well being’s (NIH’s) Cardiovascular Well being Research (CHS), a long-term observational research of threat components for heart problems in Individuals aged 65 and older. A number of blood biomarkers have been measured at baseline and once more throughout follow-up, together with ranges of the gut-microbiome generated trimethylamine N-oxide (TMAO) and two of its key intermediates, gamma-butyrobetaine, and crotonobetaine, derived from L-carnitine, considerable in purple meat.

Highlights

• On this community-based cohort of older U.S. women and men, increased intakes of unprocessed purple meat, whole meat (unprocessed purple meat plus processed meat), and whole animal supply meals have been prospectively related to the next incidence of ASCVD throughout a median follow-up of 12.5 years.
• The optimistic associations with ASCVD have been partly mediated (8-11 % of extra threat) by plasma levels of TMAO, gamma-butyrobetaine, and crotonobetaine.
• The higher risk of ASCVD associated with meat intake was also partially mediated by levels of blood glucose and insulin and, for processed meats, by systematic inflammation but not by blood pressure or blood cholesterol levels.
• Intakes of fish, poultry, and eggs were not significantly associated with ASCVD.

These findings help answer long-standing questions on mechanisms linking meats to the risk of cardiovascular diseases,” said the paper’s co-first author Meng Wang, a post-doctoral fellow at the Friedman School. “The interactions between red meat, our gut microbiome, and the bioactive metabolites they generate seem to be an important pathway for risk, which creates a new target for possible interventions to reduce heart disease.”

The 3,931 study subjects were followed for a median of 12.5 years, and their average age at baseline was 73. The study adjusted for established risk factors such as age, sex, race/ethnicity, education, smoking, physical activity, other dietary habits, and many additional risk factors.

“Interestingly, we identified three major pathways that help explain the links between red and processed meat and cardiovascular disease—microbiome-related metabolites like TMAO, blood glucose levels, and general inflammation—and each of these appeared more important than pathways related to blood cholesterol or blood pressure,” said co-senior author, Dariush Mozaffarian, dean for policy at the Friedman School. “This suggests that, when choosing animal-source foods, it’s less important to focus on differences in total fat, saturated fat, or cholesterol, and more important to better understand the health effects of other components in these foods, like L-carnitine and heme iron.”

By leveraging extensive clinical and dietary data among a large elderly community, the research “links the gut microbial TMAO pathway to animal source foods and heightened atherosclerotic cardiovascular disease risks,” said co-senior author Stanley L. Hazen, section head of preventive cardiology and rehabilitation at Cleveland Clinic. “The study also argues for dietary efforts as a means of reducing that risk, since dietary interventions can significantly lower TMAO.”

More study is needed to determine if the findings are generalizable across ages and nationalities. The authors also noted that while microbiome biomarkers were directly measured in the blood, study participants’ dietary habits were self-reported, and study findings are observational and cannot prove cause-and-effect.

Ahmed Hasan, a medical officer and program director in the Atherothrombosis & Coronary Artery Disease Branch at the National Heart, Lung, and Blood Institute, part of the NIH, agrees. “While more studies are needed, the current reports provide a potential new target for preventing or treating heart disease in a subgroup of people who consume excessive amounts of red meat,” said Hasan, who was not a part of the study.

For now, consumers are encouraged to follow current recommendations for a heart-healthy lifestyle, including adopting a healthy diet that is rich in vegetables, fruits, whole grains, and other heart-healthy foods, NHLBI’s Hasan said. Other heart-healthy lifestyle changes also include aiming for a healthy weight, managing stress, managing blood pressure, getting more exercise, getting adequate sleep, and quitting smoking, he added.

Higher Levels of TMAO, Related Metabolites Linked to Higher Risk of Death

The ATVB study is part of an ongoing collaboration among scientists at the Friedman School and Cleveland Clinic to uncover the role that the gut microbiome plays in human health, especially cardiovascular health. In a paper in JAMA Network Open in May, many of the same researchers reported that TMAO and related metabolites in older adults are positively associated with a higher risk of death whether deaths were related to cardiovascular disease or another disease. Participants with the highest levels of plasma TMAO and its biomarkers had a 20 to 30 percent higher risk of death than those with the lowest levels.

This study included more than 5,000 participants from the CHS. Findings were notable because there have been few studies on TMAO and the risk of death in the general population; previous research typically looked at clinical patients with underlying conditions such as diabetes, kidney disease, and heart disease. While identified risk factors are concerning, the good news is that TMAO levels are potentially modifiable. “Now that we know more about the severity of risks associated with TMAO, we can explore effective approaches to change these levels in the body,” said the paper’s co-first author, Amanda Fretts of the University of Washington Department of Epidemiology.

References: “Dietary Meat, Trimethylamine N-Oxide-Related Metabolites, and Incident Cardiovascular Disease Among Older Adults: The Cardiovascular Health Study” by Meng Wang, Zeneng Wang, Yujin Lee, Heidi T.M. Lai, Marcia C. de Oliveira Otto, Rozenn N. Lemaitre, Amanda Fretts, Nona Sotoodehnia, Matthew Budoff, Joseph A. DiDonato, Barbara McKnight, W.H. Wilson Tang, Bruce M. Psaty, David S. Siscovick, Stanley L. Hazen and Dariush Mozaffarian, 1 August 2022, Arteriosclerosis Thrombosis and Vascular Biology.
DOI: 10.1161/ATVBAHA.121.316533

“Association of Trimethylamine N-Oxide and Metabolites With Mortality in Older Adults” by Amanda M. Fretts, Ph.D., MPH, Stanley L. Hazen, MD, Ph.D., Paul Jensen, Ph.D., MPH, Matthew Budoff, MD, Colleen M. Sitlani, Ph.D., Meng Wang, Ph.D., Marcia C. de Oliveira Otto, Ph.D., Joseph A. DiDonato, Ph.D., Yujin Lee, Ph.D., Bruce M. Psaty, MD, Ph.D., David S. Siscovick, MD, MPH, Nona Sotoodehnia, MD, MPH, W. H. Wilson Tang, MD, Heidi Lai, Ph.D., Rozenn N. Lemaitre, Ph.D., MPH and Dariush Mozaffarian, MD, Ph.D., 20  May 2022, JAMA Network Open.
DOI: 10.1001/jamanetworkopen.2022.13242

The study was funded by the National Heart, Lung, and Blood Institute. 

Both the ATVB and JAMA Network Open studies support the importance of the microbiome and specific metabolites to human health, with the ATVB paper specifically linking the gut microbiome with meat intake, and impacts on heart health.