Is red meat really bad for us?
Red meat is the subject of countless controversial debates. While nutritional guidelines have advised limiting its consumption for many years, the research supporting this recommendation is weak and often relies on inappropriate analyses methods.
Broadly speaking, we have two ways of researching the nutritional effects on chronic disease: Observation studies and intervention studies. Intervention studies are much higher in the ladder of reliability and quality of evidence, however, they are much more difficult and expensive to conduct.
Much of the published research on red meat consumption is based on observational studies. While observational studies provide a useful way to identify hypotheses that exist between certain foods and diseases, it is near impossible to infer causality from this type of analysis. There are many possible confounding factors, and data collection methods are not very reliable .
In 2019, the Annals of Internal Medicine published three meta-analyses of observational studies showing that eating red meat poses minimal health risks for most people and that even our certainty about that link is weak . The authors offered a set of recommendations that most people can continue their current levels of meat consumption. These findings go against much of the established guidelines on red meat, and the articles received a lot of backlash and criticism. This threw even more confusion to the red meat debate. How can so many conflicting findings come out of red meat research?
The advantages of these studies were that they were all meta-analyses, reviewing all evidence that came before, so they cannot be accused of cherry-picking. However, they are still based on observational studies, and can therefore be said to be subject to significant confounding. Higher quality intervention studies would provide better evidence. And these do exist. In a fourth analysis on this subject, the researchers examined randomised controlled clinical trials that compared diets with varying amounts of red meat for at least 6 months. They concluded that “red meat may have little or no effect on major cardiometabolic outcomes and cancer mortality and incidence.” 
As with most nutrition topics, the question of whether red meat is healthy or not is very context-dependent. Red meat is a nutrient-dense food that is an important source of complete protein with all essential amino acids, and highly bioavailable iron, zinc, selenium, and B vitamins. However, it is important to eat meat in a 'nose-to-tail' way, ensuring intake of organ meats and gelatinous meats, alongside muscle meats. This provides a more favorable amino acid profile as well as important micronutrients needed to balance out those found in muscle meats only.
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