09 Nov STUDY FAILS TO FIND EVIDENCE THAT RED MEAT IS LINKED TO INFLAMMATION
MedicalResearch.com Interview with:
Dr. Alexis C. Wood
United States Department of Agriculture (USDA)/ARS
Children’s Nutrition Research Center
Baylor College of Medicine, TX
MedicalResearch.com: What is the background for this study?
Response: We know (we think!) that what we eat has a big influence on our health. However, discovering which foods influence our health, and how, is highly challenging. Research investigating this topic should be seen as an on-going process as new results and new study methods emerge, and as the food environment shifts.
Red meat is often considered a food that should be minimized in diets designed to support good health. This may seem surprising as red meat is a good source of protein and many other nutrients, but the advice to limit red meat intake is based on several large-scale studies showing associations between red meat consumption and the development of conditions such as type 2 diabetes, and other cardiovascular disease risk related factors. However, newer research, with different designs or approaches, has struggled to conclusively support this association; for example, in studies where the amount of red meat in people’s diet is manipulated, we do not see the expected increases in risk. Other studies have suggested that any associations between red meat intake and chronic disease may reflect confounding effects by adiposity – that is, the increased risk of disease really reflects the increased risk associated with a higher BMI.
MedicalResearch.com: What are the main findings?
Response: Our main finding was that red meat intake, for both processed and unprocessed forms of red meat, was not associated with inflammation (a risk factor for some chronic diseases of adulthood), when we adjusted for people’s BMI.
We also looked for associations between unprocessed red meat intake and plasma metabolites. We found that red meat intake was associated with lower levels of an amino acid in the blood, an amino acid which has anti-inflammatory effects. However, red meat was not a major influence on levels of this amino acid in the blood, suggesting again that there are other factors that drive this inflammation pathway.
MedicalResearch.com: Are processed meats/other foods known to directly cause inflammation?
Response: I think it is very difficult to say that any certain foods are ‘known’ to have any effects on health! As I say, we need to keep refining and approving our studies, weigh up all the evidence, and make an estimate of how likely a given food is to increase the risk of inflammation. Currently, it seems that high amounts of saturated fat, or high amounts of saturated fats that are not balanced by certain anti-inflammatory unsaturated fats, are good candidates for increasing inflammation.
Therefore, foods which meet this nutritional profile (i.e., are high in saturated fats only), are thought to be the most likely foods that contribute to increased inflammation.
MedicalResearch.com: What should readers take away from your report?
Response: Readers should be aware that we have another line of evidence suggesting that unprocessed red meat does not negatively impact health. Therefore, unless advised otherwise by your medical practitioner(s), reducing the amount of unprocessed red meat you eat, in and of itself, may not be the highest priority for promoting health.
MedicalResearch.com: What recommendations do you have for future research as a results of this study?
Response: Our study was observational, meaning that we asked people about their habitual diet while simultaneously measuring inflammation and metabolites (including the amino acid associated with unprocessed red meat intake) in their blood, and looked for associations. This approach has many benefits, but also, like all study designs, has many limitations.
Therefore, I would recommend that future studies include trials where the amount of red meat someone eats is manipulated, as well as studies in animals which are kept in highly controlled environments.
Our research groups plan to extend this study by looking at other aspects on biology, in addition to metabolites, and by using longitudinal data which can look at changes in diet and disease risk, over time. We are excited to see what these data show!
MedicalResearch.com: Is there anything else you would like to add? Any disclosures?
Response: Sure. Firstly, this study was funded by the Beef Checkoff, and Beef Checkoff spending is overseen by The Cattlemen’s Beef Board (CBB) as well as the USDA. Beef Checkoff was not involved in the study at all (we actually used data collected in 2000-2002!) and were not even aware of the results until they had been submitted for publication. Beef Checkoff have not been involved in this interview either, and indeed, I don’t think Beef Checkoff are aware I am giving this interview – they give their scientists a lot of freedom. However, the results from any scientific study should be seen in the light of findings from other studies seeking to address the same question. Readers should therefore be aware that not all studies report a lack of association between red meat consumption and inflammation.
I have also received funding from Sabra Dipping Co, Hass Avocado Board, Ionis Pharmaceuticals, the Institute of Life Sciences, and Unilever R&D, as well as from The American Heart Association and the National Institutes of Health.
Finally, I would like to remind readers that why we eat certain foods (or do not) is extremely complex. It reflects so many interacting factors, and we should never forget that many forms of privilege can contribute. I hope our recent study provides a data point – just one data point among many – that helps people understand the how foods may associate with health but should not be used for any other purpose.
Citation:
Alexis C. Wood, Goncalo Graca, Meghana Gadgil, Mackenzie K. Senn, Matthew A. Allison, Ioanna Tzoulaki, Philip Greenland, Timothy Ebbels, Paul Elliott, Mark O. Goodarzi, Russell Tracy, Jerome I. Rotter, David Herrington,
Untargeted metabolomic analysis investigating links between unprocessed red meat intake and markers of inflammation,
The American Journal of Clinical Nutrition,
Volume 118, Issue 5,2023, Pages 989-999,
ISSN 0002-9165,
https://doi.org/10.1016/j.ajcnut.2023.08.018
The information on MedicalResearch.com is provided for educational purposes only, and is in no way intended to diagnose, cure, or treat any medical or other condition.
Some links may be sponsored. Products are not endorsed.
Always seek the advice of your physician or other qualified health and ask your doctor any questions you may have regarding a medical condition. In addition to all other limitations and disclaimers in this agreement, service provider and its third party providers disclaim any liability or loss in connection with the content provided on this website.