Grass fed vs Corn fed...a question that might still be confusing to most

I be here are still many who do not know the difference between grass fe and corn fed beef or grass finished or if it is really beneficial to eat organic meats. I found this article informative and it helps explain some of the differences and the nutritional benefits to you.

I highly recommend only eating organic 100% grass fed beef, dairy products and being particular about the labels and certifications of such products.

Grass-Fed Beef: Marketing Jargon or Quality Promises?

By Whitney Crouch, RDN, CLT

“Natural.” “Humanely raised.” “Environmentally friendly.” “Agriculturally sustainable.” “Grass-fed.” “Pastured.” Terms that are, essentially, meaningless. These are all declarations that are not validated by any standardized methodology or verified by a United States governmental body, so these terms cannot actually help consumers rely on the quality of the beef they purchase.1

There are many factors to consider when looking at beef quality, and, as the previously mentioned marketing terms suggest, individuals often do consider different aspects of how the animal was bred and raised when purchasing meat for consumption. 

What’s the difference when it comes to beef? 

The American Heart Association (AHA) recommends that Americans reduce their red meat intake in an effort to reduce saturated fats in the diet and increase “healthy” fat intake, such as those found in plants and fish.2 To reduce saturated fat from red meat, the AHA further recommends consumers look for lean beef (round, sirloin, chuck, loin), buy “choice” or “select” grades of beef rather than “prime,” and choose lean (or extra lean) ground beef with no more than 15% fat.2 They do not, however, discuss how the beef cattle’s feed affects its nutrient profile. 

Grass-fed, predominantly grass-fed, or 100% grass-fed

Beef cattle raised for consumption are usually all raised on pasture for the first 6-9 months of life. After these first few months, and weaning from the mother, all cattle are reared by using conventional methods or pastured means.

Approximately 95% of the beef cattle in the United States continue to be “finished,” or fattened, on grain for their last 160 to 180 days (about 25-30% of their life).3 The average weight gain is 2.5-4 pounds per day. While most of a calf’s nutrition until it is weaned is from grass, feedlot rations are generally composed of 70-90% grain and protein concentrates.4

Technically, the conventionally raised type of meat could be labeled “grass-fed,” because the cow did live off of foraging for the first 6-9 months and there is no longer a “USDA Process Verified Grass-Fed” label that creates standards for this term.5-6 The USDA previously certified meats from farmers who claimed to only feed the animals grass (forage); however, there was no verbiage stating that the animals had to forage their own food, so they effectively could have been on a feedlot receiving harvested grasses. Currently, the Food Safety and Inspection Service (FSIS) of the Department of Agriculture (USDA) reviews and approves all labels on meat to verify that the products are properly labeled according to what information is submitted to them, and nongovernment certifying bodies are working to verify and maintain consistent standards for labeling.1 If 95% of beef is conventionally farmed, this leaves the other approximately 5% of cattle to the grass-fed production method, and the lines can get a little blurry with regard to labeling. 

Grass-fed animals are typically raised on grasses for their entire life, from birth to slaughter. This, however, does not mean that the cattle have been out on pasture daily, nor does it mean they are free from antibiotics or growth hormones. Incidentally, there are also no standards regarding antibiotic or growth hormone use in beef cattle. 

When it comes to body composition, grass-fed cows tend to be leaner than their age-matched, grain-fed counterparts.3 In comparison to conventionally-raised and grain-finished cattle, if adequate energy is supplied to the grazing cattle, grass-fed cattle may be expected to gain 2.0 to 2.5 pounds per day.3

Studies show that there are differences in the fatty acid profiles of beef finished on pasture/grass, as opposed to grains.7-10

Overall, a grass-fed animal is leaner than its grain-fed counterparts, and the composition of the fat in the grass-fed animal’s meat has slightly increased levels of omega-3 polyunsaturated fats and reduced amounts of monounsaturated and saturated fats as compared to grain-fed animals.7-10 It is also important to note that grass/forage variety and form, as well as cattle breed, have a significant impact on the nutritional profile of beef.7 

The higher trace amounts of omega-3 fatty acids docosapentanoic acid (DPA), eicosapentaenoic acid (EPA), and docosahexanoic acid (DHA) all support a healthier balance of fats in the diet when consumed over time; however, if the goal is to increase omega-3 fatty acids in the diet, even grass-fed meat cannot provide the amounts of these omega-3 fatty acids that are found in in fatty fish, such as salmon.7 

Does swapping grain-fed meat for 100% grass-fed red meat actually have an effect on blood levels? To answer that question, researchers conducted a study where healthy people replaced their usual grain-fed red meat intake with three portions per week of grass-fed red meat (beef and lamb). Lab tests after four weeks confirmed significantly higher levels of omega-3 fatty acids in the blood after grain-fed meat consumption. This demonstrates intake of grass-fed meats, rather than grain-fed meats, may help individuals achieve healthier, more balanced fatty acid levels over time.11

It’s not just the fat that’s different. The antioxidant values differ as well. 

In addition to increased ratios of healthy fats, vitamin E levels are higher in pasture-raised meat. This characteristic is not only beneficial to the individual consuming the meat, but it also helps to prevent oxidation of the meat between slaughter and consumption.12 Research has shown  a seven-fold increase in β-carotene levels in grass-fed beef over grain-fed beef.13

Shopping for quality

With these factors in mind, consumers should look for “100% Grass-Fed” on labels, as there are factors that could lead a herd to receive varying amounts of grains to prevent malnourishment, including seasonal changes to forgeable food, digestibility of forgeable grasses, lack of grazing land, or population-dictated food demands.3

While these meats can still be considered predominantly grass-fed, having even a few days of grain negates the “100% Grass-Fed” label. When shopping for beef, one should inquire with the farmer or butcher about the animal’s feed and grazing habits. If a consumer is shopping for a product derived from the protein-only portion of the grass-fed beef (as with collagen peptides and related products), it may be helpful to keep in mind that the fatty acid profile does not play a role here. Look for labels that disclose “100% Grass-Fed” or “Predominantly Grass-Fed,” and when in doubt, ask questions. 

Here are a few other third-party labels one can look for to verify meat quality:1

PCO Certified 100% Grassfed: Beef is certified as both organic and 100% grass-fed (after weaning), with no grains in the diet. An “organic” designation means no antibiotics or growth hormones were used during the animal’s rearing, and no synthetic pesticides were used on the pastures the animal grazed on.

Animal Welfare Approved Grassfed: Animals receive humane treatment from birth to slaughter with continuous access to pasture. This designation prohibits use of feedlots. No growth hormones are used in these animals, and no pesticides are used on their pastures; however, antibiotics can be administered to treat sick animals. Branding and dehorning are prohibited; however, castration and disbudding of horns are permitted before specific ages. Animals are given a 100% grass- or forage-based diet after weaning.

American Grassfed: Animals are grass-fed throughout their entire lives (after weaning), with no grains in the diet. The animals had continuous access to pasture, and when grazing on pasture was not possible (because of weather or other such conditions), a grass-based forage was provided. The standards also prohibit antibiotics, growth hormones, and the use of certain parasiticides. Standards do, however, allow the use of pesticides and herbicides on pasture, as well as genetically engineered alfalfa.

References

1. Rangan U et al. Consumer Reports. Food Safety and Sustainability Center. Beef report. Published August 2015. Available at: https://www.consumerreports.org/content/dam/cro/magazinearticles/2015/October/Consumer%20Reports%20Food%20%26%20Sustainability%20Center%20Beef%20Report_8-15.pdf. 
2. American Heart Association. Meat, poultry, and fish: picking healthy proteins.https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/nutrition-basics/meat-poultry-and-fish-picking-healthy-proteins. Updated March 26, 2017. Accessed January 16, 2019. 
3. Williamson JA et al. Penn State Extension. Grass-fed beef production. https://extension.psu.edu/grass-fed-beef-production. Updated March 7, 2018. Accessed January 17, 2019. 
4. United States Department of Agriculture: Economic Research Service. Cattle & beef, sector at a glance. https://www.ers.usda.gov/topics/animal-products/cattle-beef/sector-at-a-glance/. Updated August 22, 2018. Accessed January 17, 2019. 
5. United States Department of Agriculture: Agricultural Marketing Service. Grass fed small & very small producer program. https://www.ams.usda.gov/services/auditing/grass-fed-SVS. Accessed January 16, 2019. 
6. United States Department of Agriculture: Agricultural Marketing Service. Notice of withdrawal of livestock and meat marketing claims. https://www.ams.usda.gov/content/notice-withdrawal-livestock-and-meat-marketing-claims. Published January 11, 2016. Accessed January 16, 2019. 
7. Van Elswyk ME et al. Impact of grass/forage feeding versus grain finishing on beef nutrients and sensory quality: the U.S. experience. Meat Sci. 2014;96(1):535-540. 
8. Duckett SK et al. Effects of winter stocker growth rate and finishing system on: III. Tissue proximate, fatty acid, vitamin, and cholesterol content. J Anim Sci. 2009;87(9):2961-2970. 
9. Duckett SK et al. Effects of forage species or concentrate finishing on animal performance, carcass and meat quality. J Anim Sci. 2013;91(3):1454-1467. 
10. Leheska JM et al. Effects of conventional and grass-feeding systems on the nutrient composition of beef. J Anim Sci. 2008;86(12):3575-3585.
11. McAfee AJ et al. Red meat from animals offered a grass diet increases plasma and platelet n-3 PUFA in healthy consumers. Br J Nutr. 2011;105(1):80-89. 
12. Fruet APB et al. Oxidative stability of beef from steers finished exclusively with concentrate, supplemented, or on legume-grass pasture. Meat Sci. 2018;145:121-126. 
13. Daley CA et al. A review of fatty acid profiles and antioxidant content in grass-fed and grain-fed beef. Nutr J. 2010;9:10 

The PCO Certified 100% GrassFed logo is owned by Pennsylvania Certified Organic.
The Certified Animal Welfare Approved by AGW logo is owned by A Greener World.
The American Grassfed logo is owned by the American Grassfed Association.