Effects of Conventional Grass Fed Beef
November 2015 Issue
Grass-Fed vs Conventional Beef
By David Yeager
Today's Dietitian
Vol. 17 No. 11 P. 26
Research suggests grass-fed beef may be healthier than its conventional cousin.
As the debate about whether Americans should eat less beef rages on, a subdebate about the relative benefits of conventional vs grass-fed beef is taking place.
There's no question that grass-fed beef is gaining in popularity and market share, with demand growing at an annual rate of 25% to 30% per year over the past decade.1 In 2013, retail sales of grass-fed beef surpassed $400 million, compared with less than $5 million in 1998.1 Although people who are used to eating conventional beef may not enjoy the "wild" taste of grass-fed beef or its chewier texture, others prefer it. Taste often is the top consideration, but one question on the minds of many consumers is whether grass-fed beef provides any health benefits above and beyond conventional beef.
Determining the relative health benefits of grass-fed beef can be complicated, and many clients may look to dietitians for answers. To begin comparing, it's important to understand the definition of grass-fed vs conventional. Conventional, or corn-fed, beef is the most widely produced type of beef in the United States. These animals usually spend part of their lives on pasture or range, but they're moved to feedlots at 12 to 18 months of age, where they're typically separated into groups of 100 animals and live in pens that allow between 125 and 250 feet of space per animal.2 They spend approximately the last four to six months of their lives on the feedlots and are fed a closely monitored, grain-based diet.2
To be classified as grass-fed, the USDA Grass Fed Marketing Claim Standard stipulates that, after weaning, ruminants must be fed only grass; forage, which are herbs other than grass; and cereal grains in their vegetative, pregrain states, and have continuous access to pasture during the growing season.3 They can't be fed grains, such as wheat and corn or their byproducts.3 Routine vitamin and mineral supplementation in the feed is allowed.3
No stipulations exist within the USDA's Grass Fed labeling program regarding the use of antibiotics, growth hormones, or GMOs in the animal feed.4 To make claims that the beef is free of antibiotics and growth hormones, or that no genetically modified feed was given to the animals, producers have to apply for additional label designations such as "USDA Organic."4 Some organizations, such as the American Grassfed Association and the Food Alliance, have developed grass-fed standards that are more comprehensive than those of the USDA.5,6
What's the Beef?
Mary Jo Forbord, RD, a farmer and co-owner of Prairie Horizons Farm in Starbuck, Minnesota, farms 150 head of grass-fed cattle on 480 acres with her husband. They've grown both grass-fed and conventional cattle, and Forbord says grass-fed beef is significantly less labor- and energy-intensive. Feed for conventional cattle is expensive and must be closely rationed to achieve maximum growth and production. Also, conventional cattle often are given hormones to stimulate growth or regulate reproduction. The health of the animals is important, but only as it relates to their ability to be sold. Since switching to grass-fed beef, the Forbords' per capita vet bills for their herd are less than those for their dogs.
"We are enjoying farming a lot more now," Forbord says. "If we had to farm the way we did when we left commodity agriculture, we wouldn't be farming anymore. The focus in commodity agriculture is on quantity more than quality or health attributes."
The Forbords' farm, like most farms in the Midwest, is situated on the tall grass prairie, which once fed 60 million bison. Although conventional farming had stripped away many of the native plants, Forbord says the seed bed of the prairie remained intact and, since she and her husband began raising grass-fed cattle, many native plants and grasses, of which there are hundreds of species, have returned. Forbord also has noticed an increase in the diversity of animals, birds, and insects that live on the land.
The Forbords' cattle graze year-round and get their food from pastures and the prairie, while helping to keep the perennial woody shrubs that have repopulated the land in check. The Forbords rotate their cattle to fresh pasture daily to stimulate plant diversity and prevent overgrazing. The animals receive vaccines but aren't fed hormones or antibiotics. Their only supplemental food is hay from the Forbords' land, which they eat during the winter months. The cattle drink fresh water from a portable tank attached to one of several pipes that run from the farm's well to its pastures. The tank is moved each time the cattle move. Forbord estimates that it takes one to two acres to produce a ready-for-market animal. Rather than following a strict timetable, the Forbords rely on visual inspections to decide when an animal is ready to be sold.
Chewing the Fat
Another advantage of raising grass-fed cattle is the healthier fat profile of their beef compared with conventional beef. There's little scientific literature comparing a human diet of grass-fed beef to a diet of conventional beef, but a growing body of research describes the differences in the animals' fat profiles. These differences may have implications for human health.
"Grass-fed animals have a different muscle composition than grain-fed animals. The difference is mostly in the type and amount of fatty acids," says Artemis P. Simopoulos, MD, FACN, an endocrinologist; founder and president of the Center for Genetics, Nutrition and Health; and author of The Omega Diet . "For example, animals in the wild that eat grass have more meat, less fat, less saturated fat, and more polyunsaturated fatty acids. And they have, particularly, a higher amount of omega-3 fatty acids. So, during evolution, when nothing was domesticated, human beings got their omega-6 and omega-3 polyunsaturated fatty acids, particularly EPA and DHA, directly from their diet, and they were balanced almost in equal amounts."
What grazing animals ate didn't change significantly from the time humans started domesticating livestock until the past century, but as agricultural practices became more industrialized, the ratio of omega-6 to omega-3 fatty acids (EPA, DHA, and alpha-linolenic acid) in livestock began to shift. Charles Benbrook, PhD, a scientist who has studied the impact of animal rations on meat quality, says animals fed grain—mostly corn—in feedlots may grow faster, but the growth comes at a price: The grain feed increases the levels of omega-6 fatty acids and reduces the level of omega-3 fatty acids in the animals.
"It moves the nutritional quality of the fat from highly desirable, with a grass-fed animal, to not terribly beneficial," Benbrook says. "The size of the shift is quite remarkable. A number of studies have documented omega-6 to omega-3 ratios in grass-fed beef on the order of 1:1 to 3:1, whereas in animals that spend the last portion of their lives on feedlots, the ratios can be between 5:1 and 7:1. It really is a very substantial shift."
The shift from omega-3 fatty acids to omega-6 fatty acids is significant because research has shown that omega-6 fatty acids promote a proinflammatory state in the human body, says Evelyn Tribole, MS, RD, author of The Ultimate Omega-3 Diet . Inflammation has been implicated as a contributor to many chronic diseases.7-9 Tribole says eating foods with higher levels of omega-6 fatty acids interferes with the health benefits of omega-3 fatty acids.
"Most Americans are deficient in [the omega-3 fatty acids EPA and DHA] to begin with, and because omega-3s and omega-6s compete with each other, if you eat too much omega-6, it creates a proinflammatory situation in the body," Tribole says. "Once they're inside the body, the omega-3 compounds and the omega-6 compounds compete for the same kinds of enzymes. Whichever compound is predominant is going to win the enzymes."
When viewed as part of a larger shift in the American diet between the 1930s and 1950s, Benbrook says many scientists believe there's cause for concern. In the 1930s, the overall ratio of omega-6 fatty acids to omega-3 fatty acids in the American diet was between 3:1 and 4:1. By the early 1950s, it had grown to around 10:1, largely due to the widespread introduction of margarine, trans fats, soybean oil, and large-scale livestock operations that relied on feedlots and grain feed.
"There's fairly wide agreement that a diet with 10 parts of omega-6 fatty acids for every part of omega-3 fatty acid is not healthful, and it will be a risk factor for overweight, diabetes, cardiovascular disease, and any disease with its roots in inflammation, which would include dementia and the mental diseases of aging," Benbrook says. "Many scientists are convinced that this particular shift in the diet may be as important as the general shift towards excessive caloric intake, and it certainly may be more important than total fat intake. That's one of the interesting debates that's going on now in the medical community. Many doctors feel that we've put too much focus on overall fat content and not enough emphasis on the quality of the fat."
Although many researchers believe that higher levels of omega-6 fatty acids in the diet contribute to inflammation and therefore chronic disease, others believe these findings are based on minimal evidence, and that in humans higher intakes of omega-6 fatty acids haven't been associated with elevated levels of inflammatory markers.10
Home on the Range
Despite the conflicting evidence, grass-fed beef attracts consumers. The Forbords have received the USDA Certified Grass Fed label, but they haven't put it on their beef packaging because demand for their products has been growing faster than their supply, and they haven't needed an additional marketing tool. Forbord sells directly to consumers. She estimates that her farm feeds 200 families per year.
Along with the quality of the beef, Forbord says many people are interested in the quality of the animals' lives. Her customers often ask about how the animals are raised. Forbord says allowing the animals to graze is much less stressful on the animals and on her and her husband as farmers compared with conventional farming. In addition to having more room to roam, grass-fed cattle tend to live longer than conventional cattle. How long they live varies, but the Forbords have some cows aged 12 and 13. These older cows have had 10 or more calves, one each year, and they perform an important function within the herd: They're teachers. The older cows show the rest of the herd where to graze and which plants to eat at certain times of the year.
Many of the Forbords' customers also are interested in the environmental impact of the farm. Forbord says grazing helps build the soil and consumes much less energy than conventional farming. The questions about the farming process underscore a trend that Forbord has noticed: More people are taking an interest in where their food comes from. Some want to have a relationship with the people who produce their food. Others like the fact that farming grass-fed cattle tends to reduce the miles the food travels, while supporting a local economy and keeping farmers in the region. Still others see it as a way to promote environmental diversity, protect natural resources, and use the land sustainably. Whatever the reason, people's curiosity about grass-fed beef goes far beyond taste and nutrition.
"I really like having a direct relationship with our customers and being responsive to what they want and open to their requests to see our land, to see our animals, and to ask any question they want about how our animals lived and died," Forbord says. "We can give them those answers and have complete transparency about it."
Forbord also sees grass-fed beef as a potential inroad for the next generation of farmers because it doesn't require as much capital as other farming methods. With the average age of farmers approaching 60, it will become increasingly important to find new farmers.11 Forbord thinks this type of farming has the potential to repopulate some rural areas.
Getting Grass-Fed
Aside from the environmental and potential social benefits of eating grass-fed beef, health considerations shouldn't be overlooked. When advising clients, RDs often encounter people who eat more meat and fewer vegetables than what dietary guidelines recommend. As a component of the diet, however, grass-fed beef may offer some benefits.
"I recommend, when they're choosing beef, whether it's at a restaurant or they're shopping at a grocery store, to choose grass-fed or pasture-raised beef because of the better nutritional profile," Tribole says. "It's not just some new age kind of thing; there are nutritional benefits."
Where people find grass-fed beef varies by region. People who live in urban areas may need to do some research. Checking for the USDA Certified Grass Fed label on beef packaging is a good place to start.
Another way to determine whether beef is grass-fed is to ask the producer. Because of the expense associated with applying for label designations, many small farms eschew the process, even if they qualify for the designation. To help these farmers, the USDA has instituted the Grass Fed Program for Small and Very Small Producers.12 Producers with fewer than 49 head of calves or lambs from fewer than 99 ewes can qualify for a USDA Certified Grass Fed label for $108 biennially. Farmers' markets are good places to meet small producers, and many direct-sales farms advertise.
The cost of grass-fed beef also will vary, but it's typically higher than conventional beef. Sticker price doesn't tell the entire story, though. Simopoulos says most people are attracted by lower prices at the store, but they need to think about price in the context of their overall health. She says the vast majority of people eat more meat and fewer vegetables, which carries hidden costs.
"In the current food supply, unless you eat fish regularly, you can have days on end without any [EPA or DHA] omega-3s. That's why omega-3s are depleted, and that's why Western diets are proinflammatory diets," Simopoulos says. "So I recommend that people eat a diet where they get their omega-3 fatty acids practically in every meal they eat. They can eat less meat. They can eat 100 grams per day—or 3 oz—rather than 6 oz, if the meat is high in omega-3 fatty acids. If you eat half as much, the grass-fed beef is healthier and less expensive. People need to think not only about how much the food costs but how much they should eat. Get your money's worth for your health."
— David Yeager is a freelance writer and editor based in southeastern Pennsylvania.
References
1. Williams AR. Financial analysis shows grass-fed beef is good for producers. Organic Broadcaster. July/August 2014. https://mosesorganic.org/farming/farming-topics/livestock/grass-fed-beef-is-good-for-producers/. Accessed September 8, 2015.
2. Corn-fed beef and grass-finished beef. Nebraska Corn Board website. http://www.ncga.com/uploads/useruploads/corn-fedgrass-fedbeef.pdf. Accessed September 8, 2015.
3. Grass fed marketing claim standard. USDA Agricultural Marketing Service website. http://www.ams.usda.gov/grades-standards/beef/grassfed. Accessed September 8, 2015.
4. United States standards for livestock and meat marketing claims, grass (forage) fed claim for ruminant livestock and the meat products derived from such livestock. Regulations.gov website. http://www.regulations.gov/#!documentDetail;D=AMS-LS-07-0113-0001. Updated October 1, 2007. Accessed September 8, 2015.
5. Our standards. American Grassfed Association website. http://www.americangrassfed.org/about-us/our-standards/. Accessed September 8, 2015.
6. Frequently asked questions: grassfed label. Food Alliance website. http://foodalliance.org/grassfed/grassfedfaq. Accessed September 8, 2015.
7. Egger G. In search of a germ theory equivalent for chronic disease. Prev Chronic Dis . 2012;9:E95.
8. Galland L. Diet and inflammation. Nutr Clin Pract . 2010;25(6):634-640.
9. Inflammation in chronic disease. Canadian Institutes of Health Research website. http://www.cihr-irsc.gc.ca/e/43625.html. Updated April 21, 2015. Accessed September 11, 2015.
10. Willett WC. The role of dietary n-6 fatty acids in the prevention of cardiovascular disease. J Cardiovasc Med . 2007;8(Suppl 1):S42-45.
11. Ag 101: demographics. United States Environmental Protection Agency website. http://www.epa.gov/agriculture/ag101/demographics.html. Updated April 4, 2013. Accessed September 16, 2015.
12. Livestock, poultry and seed program: grass fed program for small and very small (SVS) producers. USDA Agricultural Marketing Service website. http://www.ams.usda.gov/sites/default/files/media/Grass%20Fed%20Fact%20Sheet.pdf. Accessed September 9, 2015.
Source: https://www.todaysdietitian.com/newarchives/1115p26.shtml
0 Response to "Effects of Conventional Grass Fed Beef"
Postar um comentário