- Previous speculation suggests that eating red meat leads to higher levels of inflammation and thus contributes to increased risk for cardiovascular disease.
- A recent study’s evidence, however, indicates that red meat consumption is not associated with inflammation, and instead, this link has more to do with body mass index.
- Further research is required to understand the potential negative and positive effects of consuming red meat.
Red meat is a common dietary item that specialists sometimes recommend limiting for health reasons. Researchers are still seeking to determine the benefits and health risks of consuming varying amounts of red meat.
A new study, aiming to understand this complex relationship between red meat and inflammation, found that red meat may not contribute to inflammation after accounting for body mass index (BMI).
The findings were published in the American Journal of Clinical Nutrition.
This study was a cross-sectional analysis, and researchers used data from participants who were part of the Multi-Ethnic Study of Atherosclerosis (MESA).
Researchers included participants between the ages of 45 and 84 years. They ultimately included 3,638 individuals in the final analysis. The researchers collected data from the MESA food frequency questionnaires. They also collected data on height and weight. They accounted for multiple covariates, including smoking, physical activity level, education level, age, sex, and household income.
The researchers looked at participants’ consumption of processed and unprocessed red meat and how this was associated with certain inflammation markers. They looked at plasma metabolites as they “capture the effects of diet after food is processed, digested, and absorbed, and correlate with markers of inflammation,” which helps explain the relationship between diet and health.
The study’s results found that a significant contributing factor was participants’ BMI.
When the researchers accounted for BMI, they did not find an association between red meat consumption and indicators of inflammation. This was true when looking at both processed and unprocessed red meat.
In contrast, when they did not account for BMI, there was an association between red meat consumption and inflammation.
Glutamine and processed meat
The main difference to this general finding was regarding the metabolite glutamine. Higher levels of glutamine indicate lower inflammation. They found that higher consumption of unprocessed red meat was associated with lower metabolite levels. They also found that higher levels of glutamine were associated with lower levels of C-reactive protein (CRP), another inflammation marker.
However, researchers believe that results still majorly point to the conclusion that red meat consumption alone is not majorly associated with inflammation.
Rick Miller, a dietitian at King Edward VII’s Hospital, London, the United Kingdom, and co-director of Miller & Everton, a leading men’s health, body composition and performance service, who was not involved in the study, drew attention to the link between obesity and inflammation.
“The researchers found that when adjusted for body mass index (BMI) the intake of unprocessed and processed red meat (beef, pork or lamb) was not directly associated with any markers of inflammation (C-reactive protein), thus suggesting that body weight or more likely, adiposity (holding too much body fat) and not red meat is potentially the more important driver of whole body inflammation which has been shown in RCTs [randomized control trials] on numerous indications, obesity is inflammatory.”
— Rick Miller
This research does have particular limitations.
First, as an observational study, it cannot establish any causal relationships. Second, participants self-reported their food intake and other data, which is sometimes inaccurate. The researchers note that they did not distinguish between how often participants consumed red meat and portion sizes when they were estimating participants’ average number of servings a week.
The study also only included participants who identified as white, African-American, Black, or Asian, indicating that future studies could include even more variety among participants.
There is also some risk for residual confounding, and researchers note that they could not know for sure about certain molecule annotations. The researchers note that future research can look more at underlying mechanisms.
The other major consideration is that the study received funding from the group Beef Checkoff.
Dietitian Karen Z. Berg, who was also not involved in the study, cautioned:
“Whenever I look at a study that is specifically trying to encourage consumption of a specific food or debunk myths or current guidelines for a specific food group, I always go straight to see who funded the study.”
“I am not surprised to see that Beef Checkoff is listed as the first funder. According to their website, ‘The Beef Checkoff program is a national marketing and research program designed to increase the demand for beef at home and abroad,’” she told Medical News Today.
This study cannot provide concrete guidance into how much red meat is safe for someone to eat. If future research supports these findings, it could lead to possible shifts in clinical guidance for red meat consumption. People can speak with their doctors about recommendations for red meat consumption.
However, it’s important to note that there are other reasons to limit red meat. For example, eating a lot of red meat may increase the risk of bowel cancer. Consuming large amounts of red meat with high amounts of saturated fat may increase
“The preliminary conclusion of this study found that red meat is not associated with inflammation when controlling for BMI, but carnivores shouldn’t get too excited because this leaves out all the other possible negative effects that excess consumption of red meat may have,” Berg cautioned.
“Consuming any and all types of red meat can increase BMI, increase LDL cholesterol and possibly increase a person’s risk for a heart attack or stroke. The American Institute of Cancer Research (AICR) urges people to limit red meat intake due to the strong evidence that it increases risk of colorectal cancers. There is limited evidence that suggests that it increases the risk of other cancers as well.”
— Karen Z. Berg
“This study is very useful in adding more clues to the debate of how much red meat should be consumed for optimal health but perhaps the more important question is what else are individuals doing to keep adiposity under control. Meat can be highly satiating and add nutrients to the diet not easily found or absent in some cases in plant foods,” Miller told MNT.
“Hence, as part of an obesity management regime, red meat is an important consideration in my practice,” he added.
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