Red meat raises inflammation marker CRP in clinical trials

By Dr. Sanchari Sinha Dutta, Ph.D.Reviewed by Lauren HardakerNov 17 2025

A new systematic review and meta-analysis highlight when red meat increases a key inflammation marker and why the effect appears in some groups but not others.

Study: Red meat intake and its influences on inflammation and immune function biomarkers in human adults: a systematic review and meta-analysis of randomized controlled trials and observational studies. Image credit: V75/Shutterstock.com

A systematic review and meta-analysis published in Critical Reviews in Food Science and Nutrition provides a comprehensive overview of the influence of red meat intake on inflammatory and immune biomarkers in adults.  

Why diet matters

Chronic low-grade inflammation is a significant risk factor for many non-communicable diseases, including cardiometabolic diseases and cancer. Diet is a key lifestyle factor that has been linked extensively to inflammation and immune-mediated chronic diseases.

The Dietary Guidelines for Americans recommend an adequate intake of vegetables, fruits, whole grains, unprocessed lean meats, mono- and polyunsaturated fats, vitamins, and minerals to improve immune function and reduce systemic inflammation. 

The intake of red meat has been linked to inflammation and immune dysfunction. However, there is a discrepancy and inconsistency in study findings that describe the impact of red meat intake on the risk of chronic inflammatory and immune-related diseases, including cardiovascular disease, diabetes, metabolic syndrome, and cancers.

The current systematic review and meta-analysis of existing studies aimed to explore the impact of red meat intake on inflammatory and immune system biomarkers in adults with varying health statuses.

Various electronic databases were screened to select relevant scientific studies published until May 2024. A total of 22 randomized controlled trials (RCTs) involving 1152 adults and 10 observational studies involving 438,925 adults were included in the final analysis.

How biomarkers respond

The meta-analysis of RCTS, which investigated various inflammatory biomarkers including C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), leptin, and adiponectin, revealed that higher red meat intake is associated with modestly higher blood levels of CRP. However, no such association was observed for other inflammatory biomarkers.

The findings of subgroup analysis indicated that the association between red meat intake and CRP is driven by certain factors, including a diagnosis of cardiometabolic disease, intake of red meat in mixed types (mixed, beef, and pork) and forms (processed and unprocessed), receiving a dietary intervention without energy restriction, and a red meat intake of 0.5 servings per day or more.

In contrast to the RCT findings, the meta-analysis of observational studies indicated that red meat intake is not associated with blood levels of CRP, IL-6, and TNF-α.

Implications for health

This systematic review and meta-analysis suggest that in controlled trials, consuming high amounts of red meat can lead to higher blood levels of CRP, which is an acute pro-inflammatory biomarker produced by the liver in response to infection, injury, or chronic diseases.

Specifically, the findings indicate that red meat intake was associated with increased CRP primarily in individuals with diagnosed cardiometabolic disease. Due to their pre-existing chronic, low-grade inflammatory state, these individuals may be more susceptible to the higher expression of pro-inflammatory markers in response to dietary stimuli.

High amounts of saturated fats present in red meat have been proposed in prior research to trigger inflammation by activating the innate immune receptor signaling pathway. Similarly, the heme iron in red meat is hypothesized to induce oxidative stress and inflammation through the same path.

The current meta-analysis included four RCTs that enrolled individuals with a diagnosed cardiometabolic disease. The findings indicated that although interventions tended to maintain CRP below clinically high levels, the meta-analysis still showed a significant association between higher red meat intake and higher CRP within this subgroup. This suggests that the observed association between red meat and CRP may be driven by the disease status of participants, rather than their red meat intake alone.

The amount and frequency of red meat intake may be vital determinants of blood levels of pro-inflammatory markers. A daily intake of 0.5 servings of red meat is commonly recommended in healthy dietary patterns to reduce the risk of cardiometabolic disease. This intake threshold was used as a subgroup cut-off in the present analysis, based on prior meta-analyses, rather than as a recommendation derived from the new findings. An intake above this level may increase the risk of all-cause and cardiometabolic disease-related mortality.            

In this context, the current findings indicate that blood CRP levels tended to increase only in individuals who consumed red meat at a rate of 0.5 servings per day or more.

Processed red meat accounts for nearly one-third of the total red meat intake, and it remains the primary choice of beef consumers in the U.S. Despite a high intake rate, the impact of processed red meat intake on inflammatory markers has not been adequately investigated in adult populations. Only two observational studies assessing this association were included in the current meta-analysis. One study showed associations similar to those reported for total red meat, while the other study linked higher intake of processed red meat to adverse metabolic outcomes in women.

Overall, the current findings highlight the need for more well-designed, prospective observational studies and RCTs to address the influence of consuming total, processed, or minimally processed or unprocessed red meat on pro-inflammatory, anti-inflammatory, and immune function biomarkers in adult individuals.

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