Meat: To eat or not to eat?

By Rafia Virk, PhD student in Nutrition

Meat is a staple food dating back to prehistoric times, but in recent times, people have started to associate consumption of meat with poor health, increased disease risk, and environmental stress. Let’s start with the word meat itself, which originates from an old English word “mete” which means “food in general.”  If meat means food in general, should it not be regarded as an essential component of everyone’s diet? 

Meat is an excellent source of protein and when consumed, it can provide the human body with all the essential amino acids, which cannot be produced in the body.  Research suggests that animal protein is higher in quality than plant protein and can be absorbed through our digestive system more readily (1). If you compare gram to gram, to provide an adequate daily intake of protein, a vegetarian will have to eat a lot more, to obtain the same amount of protein, as an omnivore. In addition to protein, meat contains fat which is required for the absorption of some key nutrients that are fat-soluble such as vitamins A, D, E, and K. Vegetarians can get these nutrients in their diet, but they need to consume it with fat, for it to be absorbed, and animal fat is the best source as it is not as processed as vegetable oil fats (2). Animal fat is also very stable when used in fried foods compared to vegetable oils and thus has a longer shelf life. As a bonus, food cooked in animal fat gets an extraordinary flavor, which is a biased opinion but critical to mention. Meat also provides some essential fats consisting of polyunsaturated fatty acids (PUFAs). PUFAs are needed for many functions and play a key role in the initiation and resolution of inflammation. Marine meat is a vital source of omega 3 PUFAs, docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA) which are implicated in reducing the risk for many diseases such as cardiovascular disease and improving brain cognitive functions (3–7).

Meat is also rich in many nutrients and minerals.It is the best source of vitamin B12, heme-iron, and zinc. Vitamin B12 is an essential micronutrient that is almost exclusively only obtained from animal sources and is necessary for fatty acid and amino acid metabolism in our body. Deficiency in B12 can lead to diarrhea, fatigue, dementia, and signs of nerve damage (8). Additionally, meat, especially red meat is a great source of heme iron which has higher bioavailability than non-heme iron from plant sources. Heme-iron is more than 90% of the functional iron in our body and is part of red blood cells which help supply oxygen to our tissues. People who cannot properly absorb iron or lose a lot of blood due to hemorrhage require more iron in the diet to help maintain red blood cell levels in the body. Not obtaining proper sources of iron can lead to anemia and other diseases like Alzheimer’s disease (9). Another essential mineral obtained from meat is Zinc, which, unlike iron, cannot be stored in the body and should be regularly supplied in our diet. Zinc has important regulatory, antioxidant, and catalytic functions in the body. Strict vegetarians present with zinc deficiency which can lead to increased risk for infectious diseases and impairment in physical and neuropsychological development (10).

Although meat contains many essential nutrients required for health, consumption of meat should still be controlled with respect to quantity and quality. It is true that too much of anything is bad for you, and meat is no exception, as increased meat consumption increases the risk for many diseases (11). Additionally, the quality of meat matters, as many Americans mostly consume processed meat in form of hot dogs, ham, bacon, and chicken nuggets which contain high levels of nitrites (causing oxidative stress) and heterocyclic/polycyclic amines which increase the risk for colorectal cancer (12). Since the American diet mainly includes overly processed meat in the diet, many people have decided to become vegetarians and avoid meat altogether. If not carefully monitored, people could be missing key essential nutrients which can lead to the development of illness. When considering excluding meat from your diet, it is important to recognize the nutritional value of meat as it is a vital source of nutrients that are not easily available in a plant-based diet. However, as discussed, the quality of meat has changed in recent years with the increase in overly processed meats. Additionally, the quantity of meat consumption has dramatically changed with an overconsumption of meat leading to inhumane practices in animal farming.  It could be that instead of totally excluding meat from one’s diet, people could consider decreasing the amount of meat and choosing good quality meat such as fish or grass-fed chickens and cows. I hope I have convinced you, to at least do more research about meat and rethink your diet! Meat: to eat; most definitely!

Peer-edited by: Laetitia Meyrueix, PhD

Image credit: iStock by Getty Images

References: 

1. Marinangeli, C. P. F., and J. D. House. 2017. Potential impact of the digestible indispensable amino acid score as a measure of protein quality on dietary regulations and health. Nutr Rev. 75: 658–667. https://doi.org/10.1136/bmj.l4697. 
2. Halvorsen, B. L., and R. Blomhoff. 2011. Determination of lipid oxidation products in vegetable oils and marine omega-3 supplements. Food Nutr Res. 55: 10.3402/fnr.v55i0.5792. https://foodandnutritionresearch-net.libproxy.lib.unc.edu/index.php/fnr/article/view/462 
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