PROTEIN CONSUMPTION AND PRODUCTION

Fri, November 02, 2018   |    Download PDF of this article

The average American adult man consumes 75 percent more protein than is recommended; for American women, it’s 50 percent more. Animal-based foods like meat, fish, poultry, eggs, and dairy account for approximately two-thirds of this dietary protein. Yet, plant-based foods such as nuts, seeds, beans, peas, legumes, grains, and cereals are also important sources of protein. The amount and types of protein consumed can have significant effects on the environment and the risk of chronic diseases and premature death. Culinary and foodservice professionals have an important role to play in leading and inspiring a balance of protein sources on Americans’ plates that is healthier for both people and planet.

Red meat consumption in the U.S. continues to decline steadily, with beef consumption in the U.S. now at the lowest level in over two decades. In the U.S., total meat consumption (red meat plus poultry) still remains high, at 59.2 kg per capita in 2015, which is the fifth highest consumption rate globally. The continued decline in the U.S. also is a departure from global trends. In recent decades, meat consumption has increased sharply worldwide, especially in developing countries. That said, there are important distinctions between red meat and poultry in terms of both environmental and human health effects, as well as between red meat and other protein sources.

ENVIRONMENTAL IMPACTS

Animal-based foods contribute disproportionately to the total environmental costs of food production. The main reasons for these impacts are enteric emissions from the digestive activities of ruminant animals such as beef and milk cows, emissions to air and water from manure management, and the growing of crops to produce animal feed. Thirty-eight percent of the U.S. corn crop, which uses more land than any other crop, goes to feeding livestock (please see Sankey Diagram on page 28 of the Annual Report for a snapshot of overall corn usage). Feed conversion efficiencies, or how effective an animal is at converting feed into edible meat, vary greatly by species. By one estimate, it takes 36 calories of feed to produce one consumed calorie of beef. This ratio is 11:1 for pork, 9:1 for poultry meat, about 6:1 for eggs and dairy, and sometimes lower than 2:1 for fish and insects. These differences, combined with methane emissions from ruminants, explain the variability in GHGE from animal protein sources seen in the figure on page 29 of the Annual Report.

Production methods certainly influence the environmental impact of animal-based foods, but the type of protein chosen matters more. Popular alternatives must be fully assessed before being lauded as solutions. For example, pasture-based beef production can have many local environmental advantages over grain-fed beef such as reduced water use and nutrient losses, and greater ecosystem biodiversity. Yet, often the GHGE associated with grass-fed beef are higher than grain-fed. Under some conditions and production methods, significant carbon sequestration under intensively managed pastures can be achieved, which may offset other GHGE, but this cannot be assumed. In summary, the GHGE of beef can be high, whether grain-fed or even when grass-fed, whereas dual-purpose systems, producing both milk and beef, may offer the lowest burden per unit of food produced. In the end, switching production methods alone will not be enough: we need to first serve much less beef, and then seek a premium product such as sustainably produced grass-fed, which may carry a higher price point, reflecting higher costs (a strategy sometimes termed “less meat, better meat”—in principle, allowing food costs to remain constant). Future technical advances are expected to improve the environmental efficiency of food production, but analysts project that these improvements will be insufficient to reach GHGE reduction goals, meaning shifts in eating habits are needed to reach such targets.

HEALTH IMPACTS

Red meat consumption also has significant impacts on human health. The science is clear that regular consumption of red meat contributes to higher risk of chronic diseases and premature death. Diets that include substantial amounts of red meat and products made from these meats increase risk of diabetes, heart disease, and some cancers. Nearly one in 10 premature deaths could be prevented in the U.S. if American adults were to cut their current red meat consumption to less than half a serving per day.

In 2015, the International Agency for Research on Cancer (IARC) of the World Health Organization (WHO) announced that processed meats such as hot dogs, bacon, and sausages should be classified as carcinogenic (Group 1) to humans for colorectal cancer, and unprocessed red meats should be classified as “probably carcinogenic” (Group 2A). It was estimated that a 50-gram portion (1.8 ounces) of processed meat eaten daily increases the risk of colorectal cancer by 18 percent. Red and processed meats have already been associated with type 2 diabetes, cardiovascular disease, and other chronic disease; an increased cancer risk further underscores the need for consumers to reduce their consumption of meats, especially processed meats.

On the flip side, there is increasing evidence to support the notion that replacing animal protein with plant protein can help prevent chronic diseases. In a large study from eight European countries, higher intake of animal protein was associated with an increased risk of developing type 2 diabetes, whereas plant protein was not associated with risk. In a recent analysis of 131,342 participants from the Nurses’ Health Study and Health Professionals’ Follow-Up Study who were followed for two to three decades, higher intake of animal protein, particularly red and processed meats, was associated with increased risk of death from cardiovascular disease. They also found that substituting plant protein for animal protein, especially that from red and processed meat, was associated with lower risk of death from cardiovascular disease.

The health effects of protein sources depend on comparison or reference foods. Compared to red meat, eggs and dairy products have less adverse health impacts. There is little evidence that moderate consumption of eggs (up to one egg per day) has adverse effects on the risk of chronic diseases. However, consumption of dairy products may affect human health in complicated ways, depending on the types of dairy products. Total dairy consumption has little benefit on body weight, diabetes, and cardiovascular disease, although there is some evidence that higher consumption of fermented dairy products (especially yogurt) is associated with lower risk of weight gain and type 2 diabetes.

DIETARY CHANGE

Eating out more and eating meat less have gone hand in hand for more than a decade, as consumers continue to spend more food dollars on meals prepared by culinary professionals while red meat consumption declines. The restaurant industry continues to lead a positive change in the American diet both by shifting away from red meat, creating more scratch-cooked, plant-based options, with plant-forward concepts like bowls now rapidly growing on American menus. Restaurants are also introducing diners to a new generation of meat alternatives, such as the recent debuts of Impossible Burger and Beyond Burger in restaurants before entering the grocery market. Moves by the restaurant industry to serve more poultry—and, more recently, more plant-based foods—have led to a significant change in our nation’s diet.

Both restaurants and food manufacturers also have been responding with a flood of meatless protein alternatives, some scratch-cooked and others manufactured from quite novel sources. Options abound for replacing meat with plant-based proteins—from traditional foods like seitan, tofu, and tempeh, to quinoa, lupine, and wheat-, pea-, and rice-based food products designed to combine with meats. Insect-based proteins, which appear to have a very low environmental footprint, have also emerged on the menus of some restaurants, and as featured ingredients in new snack foods. The prevalence of alternative “meat” products in the marketplace far outpaces the research on their environmental and health impacts, while scratch-cooked substitutes offer a clearer benefit. Preliminary results show that most “meat” replacements have reduced environmental impact, but some evidence suggests that plant-based protein sources requiring significant processing, such as soy protein isolate, may approach some of the environmental footprints of animal-based foods because of energy requirements in processing.

Recent years have also seen numerous studies exploring the environmental and human health effects of dietary change and the potential for diet shifts as a climate mitigation strategy. There is clear consensus that reducing animal-based foods in the diet can result in lowered environmental impact. These patterns can be seen among self-selected diets in the U.S. Using the National Health and Nutrition Examination Survey (NHANES) dietary recall data, researchers examined the linkages between diet, health, and environmental impact. Individuals’ diets from NHANES were ranked based on the GHGE associated with their production. Compared to those with high dietary GHGE, those in the lowest emission group consumed more than twice as much plant protein foods and less than half as much animal protein foods, and also ate more poultry and less red meat. The lowest GHGE diets (bottom quintile) included more vitamin E, folate, and dietary fiber, and less sodium and saturated fat than the highest GHGE diets. However, there was a higher content of calcium, vitamin D, and potassium in the highest GHGE diets. Shifting the diets in the highest quintile to diets with an average carbon footprint would offer 10 percent of U.S. emissions reduction targets, as submitted to the United Nations. This means that diet shift can play an important role in climate action at city and state levels, and culinary professionals can greatly influence this cultural shift. But according to a new study funded by the federal beef checkoff program, consumers who value nutrition and the environment tend to purchase less beef, so as these concerns grow, we might anticipate lower demand for red meat.

As part of that cultural shift, chefs and foodservice operators should focus on two key impacts they can have on consumers’ attitudes when it comes to proteins, through their menus— both in the design they conceptualize and the language they use. They should reduce their reliance on red meat and instead feature more plant-based dishes, including offering smaller meat portions accompanied by craveable and flavorful whole grains, legumes, and vegetables. On the menu itself, chefs should then describe dishes more holistically rather than always featuring the animal protein first, which contributes to an unbalanced perception of its importance. By using descriptions that make meat and plants equally enticing, they can create dishes that are healthier whether their diners notice it or not. Chefs also need to help consumers understand that proteins are present in most whole foods. Instead of using protein as a synonym for meat—whether it is during culinary demonstrations or on fast-casual menus where customers pick from a variety of options—chefs should instead use the term “animal protein” when they refer to such a thing. Additionally, when appropriate, chefs can speak of “plant-based protein”—a simple vocabulary shift that may go a long way.

SCORE: 3.5

Motivation aside, eating out more and eating meat less are highly correlated, as the restaurant industry continues to find ways to help its diners eat less meat, a move that also addresses climate change.

IN SUMMARY:

  • High meat consumption, particularly red meat, has harmful effects on both human health and the environment.
  • New studies add to existing evidence that shifts in eating habits toward more plant-based proteins, fruits, and vegetables can reduce the risk of certain chronic diseases, greenhouse gas emissions, and the burden on water and energy resources.
  • Motivation aside, eating out more and eating meat less are highly correlated, as the restaurant industry continues to find ways to help its diners eat less meat, a move that also addresses climate change.