As we know here at IFIC, food trends come and go all the time. One day we’re talking about the pegan diet or alkaline water, the next we’ve moved onto food combining. But some topics stay more consistent than others—like the discussion over what we should be eating to promote our own health—and, more recently, how these choices impact the world around us. Red meat stands at the nexus between these two questions, and it’s become a perennial flashpoint in the nutrition community.
Red meat: the basics
According to the U.S. Dietary Guidelines for Americans, “red meat” includes all forms of beef, pork, lamb, veal, goat, and nonbird game (e.g., venison, bison, and elk). Meats vary in fat content, and it’s recommended that people choose lean meats, which contain less than 10 grams of fat, 4.5 grams or less of saturated fats, and less than 95 milligrams of cholesterol per 100 grams and per labeled serving size (e.g., 95% lean ground beef and pork tenderloin).
Red meat is rich in protein, zinc, iron and vitamin B12, all of which are important nutrients for maintaining our health. It’s been a part of our meals throughout history, and throwing burgers on the grill in the summer or putting a rack of lamb in the oven during the holidays has become entwined with our American identity. At the same time, red meat, particularly cuts that are higher in saturated fat, has been linked to increased risk for health conditions like heart disease, type 2 diabetes and some types of cancer, the latter associated with compounds created when red meat is cooked at high heat. And its environmental impact is high compared with plant sources of protein. These pros and cons create a dilemma for individuals, governments and health-focused nonprofits as to what and how much to recommend and to whom.
The most recent controversy around red meat stemmed from a series of systematic reviews and one guideline paper that were released in November 2019 that concluded that evidence for limiting red meat consumption was weak and recommended that people continue their current level of red meat consumption. This bold conclusion ran opposite to the prevailing recommendation that people should limit their consumption of red meat and prompted backlash for both the study authors and people opposed to their conclusions.
Why all the controversy, all the time?
Red meat is a topic that perfectly encapsulates the difficulties in conducting nutrition research and translating that research into dietary recommendations.
For starters, conducting studies of what people eat and how it affects their health is marred by less-than-ideal study designs. Observational studies, in which a group of people is enrolled in a study and tracked over time, can give information on how long-term food intake is associated with risk for health conditions. However, they can only show that there’s an association between two things—say, red meat intake and cardiovascular disease (CVD). They can’t prove that one directly causes the other (i.e., eating red meat causes CVD).
Compounding these issues is the fact that the dietary information gathered in observational studies tends to be self-reported. Even if a person tries to tell the whole truth about what they’re eating every day, they’re bound to leave out key information or under- or overestimate the quantities they consume. And unfortunately, many people tend to intentionally leave out pieces of information when asked about it. Not everyone is prepared to share that they ate, say, two or three cheeseburgers in one meal. In addition, high-red-meat consumers tend to be very different from low- or no-red meat consumers in a variety of ways outside of what they eat, including physical activity, stress level, socioeconomic status and smoking or alcohol use. And importantly, red meat consumption is just one part of the overall diet—it needs to be considered with the intake of other foods and beverages as a total package.
Randomized controlled trials (RCTs) offer researchers much more control over what they’re measuring. Considered to be the “gold standard” of human research, RCTs enroll people in a study and randomize them into one of two or more groups. One group remains the “control” group and either receives a placebo (or “sham”) intervention or no intervention at all, and the other group(s) receive an intervention: for example, instructions to eat six ounces of red meat per day for a month. At the end of the study, key outcomes are measured and compared between the groups—things like body weight, cholesterol, and other markers for health might be relevant in a study on red meat.
Unlike observational studies, RCTs can prove cause and effect, and they’re not as affected by bias. The downside? They’re typically not as long in duration as observational studies, so it’s difficult to know whether the results would be consistent long-term, or if the different interventions would lead to different disease states, since many health conditions take years—if not decades—to develop. So, we need both types of studies, because both have their own attributes but also have inherent flaws.
An additional challenge to research on red meat’s effects on health is that many studies on the topic have lumped all red meat together as a category, instead of separating types of red meat that are higher in saturated fat—which is associated with increased risk for heart disease—from lean red meat, which is lower in saturated fat. Or they haven’t accounted for different cooking methods, which is important given the association between high-heat cooking like grilling or frying and the creation of compounds associated with some types of cancer. And all of this doesn’t even account for the personal and professional biases that often impact the work of researchers. Conflict-of-interest reporting can properly disclose these ties (and some have even gone so far as to suggest that nutrition study authors report what kind of diet they personally follow), but it’s difficult to fully remove bias from studies of any kind, not just those analyzing nutrition.
What do our U.S. Dietary Guidelines say?
The current set of recommendations for healthy eating in the U.S. are the 2015–2020 Dietary Guidelines for Americans. They state that “strong evidence from mostly prospective cohort studies but also randomized controlled trials has shown that eating patterns that include lower intake of meats as well as processed meats and processed poultry are associated with reduced risk of CVD in adults. Moderate evidence indicates that these eating patterns are associated with reduced risk of obesity, type 2 diabetes, and some types of cancer in adults.”
The DGAs note that much of the research they examined grouped together all meats and poultry, regardless of fat content, though some evidence has identified lean meats in healthy eating patterns. Food pattern modeling has indicated that lean meats can contribute important nutrients while remaining within recommended limits for sodium, calories from saturated fats, and total calories when consumed in recommended amounts.
The overall recommendation for the meats, poultry, and eggs subgroup in the Healthy U.S.-Style Eating Pattern at the 2,000-calorie level is 26 ounce-equivalents per week. That includes all sources of protein within this group; there is no specific number dedicated only to red meat.
Are there other red meat recommendations?
Yes. Countries around the world and global nonprofits also have guidelines on red meat consumption, including:
- Canada’s Dietary Guidelines, released in early 2019, recommend consuming plant-based sources of protein more often. When people do choose to eat animal protein, the Canadian guidelines recommend selecting foods lower in saturated fat, like lean red meat sources including wild game. They also state that foods containing unsaturated fat should replace foods containing mostly saturated fat.
- The European Union’s Food-Based Dietary Guidelines list nutrition recommendations across all member countries as well as in Norway, Switzerland and Iceland. These guidelines vary slightly from country to country, but their key consistent message when it comes to red meat is to eat it sparingly (either to reduce portion sizes, eat meat less often, or both). If a person chooses to eat red meat, it’s recommended that lean cuts be favored over fatter, richer meats.
- The World Cancer 188 金宝搏 Fund and the American Institute for Cancer 188 金宝搏 : These organizations have extensive research and recommendations across different types of foods and beverages. Related to red meat, they state, “If you eat red meat, limit consumption to no more than about three portions per week. Three portions is equivalent to about 350–500g (about 12–18oz) cooked weight.”
Each of these guidelines overlaps with the U.S. DGAs. Basically, we should limit our consumption of red meat, but there is no need to eliminate it entirely from our diet. One key consideration is that these guidelines often rely solely on research on red meat’s impact on human health. To date, its impact on the environment hasn’t been a major factor. In 2018, the EAT-Lancet Commission attempted to build a set of universal targets for food consumption that would benefit both human and planetary health. They determined that to meet the goals that they set for healthy diets by the year 2050, red meat consumption would have to be reduced by 50%, mostly coming from reducing consumption in wealthier, industrialized countries. These recommendations have been met with controversy of their own, most recently from an analysis that determined that the “planetary health” diet prescribed by the commission would be unaffordable for 1.6 billion people.
The 2020–2025 Dietary Guidelines for Americans are currently being developed, and they’re expected to be released in late 2020. For this cycle, topics and questions have been identified in advance, and Dietary Guidelines Advisory Committee members have been tasked with answering them. While no questions are directed specifically at red meat, protein recommendations from both plant and animal sources will most likely be made. There is no sign that environmental impact or sustainability will be factored into the final guidelines.
So…what should we eat?
It’s clear that the discussion of red meat is often controversial, but the consistency in healthy eating recommendations around the world indicates that it can have a place in your diet—if you want it to. Lean red meat provides protein and several important vitamins and minerals, but those nutrients can be found in other animal and plant sources of protein should you choose not to eat red meat. The decision remains a personal one, and even though most formal dietary guidance does not factor in its impact on the environment or ethical concerns, those components can be a part of making your own decisions around red meat consumption. If you do choose to include red meat in your diet, make sure to choose lean cuts that are lower in saturated fat. They may be labeled as “lean” or “extra lean” on the package. Cuts with the least amount of visible fat (called marbling) are also good options.