Red meat refers to red meat in nutrition. Red meat is high in saturated fat. 27 October 2017 WHO International Cancer is meat that turns red before cooking. Such as pork, beef, mutton, rabbit meat, etc., all mammalian meat is the preliminary reference for the list of carcinogens published by the disease research institute, and red meat (ingestion) is in the list of 2A carcinogens. Many people have heard the statement that “red meat is unhealthy” and are apprehensive about it. So what exactly does red meat do to our bodies?
Recently, a study published in Atherosclerosis, Thrombosis, and Vascular Biology (ATVB), a journal of the American Heart Association, is the first to examine the relationship between animal-derived food (ASF) and Correlations between atherosclerotic cardiovascular disease risk, proposed metabolites produced by gut microbiota and traditional pathways (eg, blood cholesterol, blood pressure, and blood sugar) on atherosclerotic cardiovascular disease risk mediation.
I. Research background
Animal source foods (ASFs), including unprocessed red meat, processed meat, fish, poultry and eggs, are a major component of many diets. The effect of these different foods on atherosclerotic cardiovascular disease (ASCVD) has been extensively studied, but remains controversial.
ASF metabolites produced by gut microbes include trimethylamine N-oxide (TMAO), derived from dietary L-carnitine (almost exclusively in red meat) and choline Metabolic production of microorganisms (present in various ASFs). The gut microbial metabolism of L-carnitine also produces two intermediates, γ-butylbetaine and crotonobetaine, each of which can be further converted into TMAO. Some studies suggest that TMAO and its intermediates produced by gut microbes may mediate the effect of ASF depletion on ASCVD to a certain extent. However, no studies have evaluated this hypothesis.
The authors investigated the prospective association of different ASFs with the development of ASCVD, as well as the production of trimethylamine N-oxide, the l-carnitine-derived intermediate γ-butane produced by gut microbes Betaine and crotonine and potential mediators of traditional ASCVD risk pathways.
II. Research methods
1. Study population
The team looked at a study of cardiovascular health in the United States that began in 1989. Participants were all over the age of 65 and 63.5 percent were women. Every 6 months, trained personnel assessed participants’ demographics, lifestyle, medical history, and other health-related phenotypes by telephone.
2. Assessment of dietary habits (exposure)
The authors focused on foods significantly associated with ASCVD, including processed meat, unprocessed red meat, and fish. In a previous meta-analysis of the general middle-aged population, the authors focused on foods significantly associated with ASCVD, including processed meat, unprocessed red meat, and fish. The authors hypothesized that processed and unprocessed red meat consumption was positively associated with ASCVD incidence and that these associations were mediated in part by plasma levels of TMAO-related metabolites; fish was negatively associated with ASCVD. In an exploratory analysis, the authors examined the association of secondary dietary exposures, including total ASF in total meat (ie, unprocessed red and processed meat), poultry, and eggs, with ASCVD. Two validated food frequency questionnaires were answered at the start of the study and between 1995 and 1996 to learn about their usual dietary habits, including the frequency of consumption of red meat, processed meat, fish, poultry and eggs.
3. Evaluation of plasma TMAO-related metabolites (mediators)
The authors investigated the effect of TMAO and its 2 intermediate gut microbe-dependent metabolites from dietary l-carnitine, γ-butylbetaine and crotonobetaine primarily by collecting fasting blood samples. Joint mediation. Pathway-specific mediated associations of each TMAO-related metabolite, as well as the mediation of plasma levels of each nutrient precursor (i.e., choline, betaine, and carnitine), were also explored.
Conceptual map of dietary exposure, trimethylamine N-oxide (TMAO)-related metabolites (mediators) produced by gut microbes, and atherosclerotic cardiovascular disease (ASCVD)
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Three. Results
1. Characteristics of the study population
Among the participants, the mean (SD) age was 72.9 years, the majority were female (63.5%), and 12.0% were non-white. The study foundSmoking men who were less active, had higher levels of diabetes, and had lower intakes of fruits, vegetables, and dietary fiber had higher intakes of unprocessed red meat. The opposite pattern was observed for fish intake, with participants with higher intakes more likely to be female, never or ever smoked, more educated, and higher intakes of fruits, vegetables and dietary fiber higher.
2. Correlation between dietary exposure and TMAO-related biomarkers
Positive associations between plasma TMAO levels and intake of unprocessed red meat, total meat, fish and total ASF, L-carnitine metabolites gamma-butylbetaine and crotonine There was a positive correlation with the intake of unprocessed red meat, processed meat, total meat and eggs, and a negative correlation with the intake of fish and poultry.
3. Association of dietary exposure with ASCVD risk (primary dietary association)
Eating more meat, especially red and processed meat, was associated with risk of atherosclerotic cardiovascular disease during an average follow-up period of up to 12.5 years increase about. Consumption of unprocessed red meat and processed meat was associated with a 15% and 11% increased risk of atherosclerotic cardiovascular disease for every 1.1 additional servings, respectively.
Total meat consumption (unprocessed red meat and processed meat), per 1.1 additional servings, was associated with an increased risk of atherosclerotic cardiovascular disease 22 % related.
Each 1.1 additional serving of total animal food intake was associated with an 18% increased risk of atherosclerotic cardiovascular disease.
No significant association was found between fish, poultry and egg intake and risk of atherosclerotic cardiovascular disease.
4. L-carnitine metabolites produced by gut microbes significantly mediate ASF-related ASCVD risk
Study finds that dietary L-carnitine produced by 3 gut microbes (TMAO, gamma-butylbetaine and crotonobetaine) There was a certain correlation with unprocessed red meat intake and ASCVD. This correlation was related to the plasma levels of these three products.
Additionally, the researchers found thatthe higher risk of ASCVD associated with meat consumption was partly related to blood sugar and insulin levels; for processed meat, it was also partly related to systemic inflammation; Blood sugar levels and inflammation may play a more important role than cholesterol or blood pressure in the association between unprocessed red meat, processed meat, and cardiovascular risk.
III. Summary
In this large community-based cohort,higher meat intake was associated with ASCVD events, partly due to the abundance of L-carnitine in red meat mediated by microbially derived metabolites. These new findings support a biochemical link between dietary meat, gut microbiota pathways and ASCVD.
This study has certain limitations: Since the majority of participants were white in the United States and over the age of 65, the findings may not apply to more Young or other ethnic groups.
The researchers say: “What we eat is altered by the bacteria in our bodies, and while this provides broad health benefits, some metabolites may Promotes diseases such as atherosclerosis and may lead to downstream adverse cardiac events.”
This also reminds us not to focus on differences in total fat, saturated fat or cholesterol when choosing foods of animal origin; and a better understanding of other ingredients in the food The health effects (such as carnitine and heme iron) are the most important. Also follow current recommendations for a heart-healthy lifestyle with a diet rich in vegetables, fruits, whole grains and other heart-healthy options.
Written by Catherine
Editor: Catherine
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