Humans that eat meat are typically referred to as omnivores. An omnivore is an animal that eats both plant and animal matter. Humans are biologically classified as omnivores as we are capable of deriving nutrients from both plant and animal sources.
Why are humans classified as omnivores?
Humans are classified as omnivores for several key reasons:
- Humans have both carnivore and herbivore characteristics. For example, we have canine teeth for tearing meat but also flat molars for chewing plant material.
- Humans can digest both plant and animal matter. We have enzymes and gut bacteria capable of breaking down fiber from plants but also animal proteins and fats.
- Both plant and animal foods provide important nutrients for human health. Meat provides protein, iron, vitamin B12 while plants provide fiber, vitamins, minerals.
- Humans are behaviorally omnivorous. In most cultures, humans eat a mix of meats and plants. Complete vegetarianism is rare.
- Humans evolved as hunter-gatherers, eating a mixed diet. Our evolutionary ancestors ate meat scavenged from animals as well as wild plant foods.
So in summary, human physiology is adapted to make use of nutrients from diverse food sources, both meat and plants. Our behavior reflects this dietary flexibility.
What are other types of diets?
While omnivore is the standard human diet, there are other types of specialized diets that restrict certain food groups:
- Vegetarian – does not eat animal flesh of any kind but consumes eggs and dairy.
- Pescatarian – vegetarian diet that also includes fish and seafood.
- Vegan – does not consume any animal products including meat, fish, eggs, or dairy.
- Flexitarian – primarily vegetarian diet but occasionally eats meat.
There are also diets that focus on specific types of animal foods:
- Pollotarian – only eats poultry including chicken, turkey, duck but no red meat or seafood.
- Pescetarian – only eats fish and seafood.
However, omnivore remains the most common human diet, consuming a blend of both animal and plant foods.
Are there any benefits to being an omnivore?
Yes, there are some potential benefits to an omnivorous diet:
- More balanced intake of essential nutrients like protein, iron, zinc, and vitamin B12 from meat alongside antioxidants, fiber, and phytonutrients from plants.
- Omnivorous diets are associated with lower risk of deficiencies like anemia or malnutrition.
- More dietary flexibility and ability to obtain adequate nutrition from diverse food environments.
- Possibly greater satisfaction and enjoyment from diet due to variety and palatability of different food groups.
However, being an omnivore does not necessitate eating meat at every meal. Most health organizations recommend limiting intake of red and processed meats due to links with chronic diseases. A plant-based diet with occasional moderate meat intake is likely optimal for most people.
What are some drawbacks or criticisms of an omnivorous diet?
There are some potential drawbacks and criticisms to address regarding an omnivorous diet:
- Meat production has significant environmental impacts related to land use, water use, and greenhouse gas emissions. Reducing meat intake can lower someone’s environmental footprint.
- Eating meat and animal products is linked to higher risks of heart disease, cancer, diabetes. Plants are nutritionally sufficient for human health.
- There are ethical objections to eating animals due to concerns about animal welfare and suffering in industrial livestock production.
- Risk of foodborne illness is higher with meat and other animal products compared to plant foods.
While humans are omnivores biologically, in modern society where plant foods are abundant, regular meat consumption may not be necessary or beneficial for health or sustainability.
What are some examples of omnivorous foods?
Here are some examples of common omnivorous foods that incorporate both plant and animal ingredients:
- Hamburgers or cheeseburgers
- Hot dogs
- Steak, chicken, or fish tacos
- Pizza with meat toppings
- Lasagna, spaghetti bolognese
- Burritos or enchiladas with meat filling
- Sandwiches with deli meat
- Breakfast sandwiches with bacon, sausage, or eggs
- Salads with grilled chicken or salmon
- Soups like chicken noodle soup or beef stew
These omnivorous foods blend animal proteins like meat, dairy, or eggs with plant foods like grains, vegetables, or fruits. An omnivorous meal plan incorporates both types of ingredients.
How much meat does the average omnivore eat?
According to surveys, this is the average daily meat consumption for an omnivorous diet in various countries:
|Country||Average Daily Meat Consumption|
|United States||270 g|
|Western Europe||173 g|
|South Korea||124 g|
The average meat intake ranges from 10 g to 270 g per day worldwide. Developed Western countries tend to have the highest level of meat consumption. The global average is around 100 g of meat daily.
What percentage of humans are vegetarian?
Currently, vegetarians make up a small minority of the global population:
- India: 35-40% vegetarian
- United States: 5-10% vegetarian
- United Kingdom: 2% vegetarian
- Germany: 9% vegetarian
- China: 4-5% vegetarian
However, rates of vegetarianism and veganism are rising in Western countries and among younger demographics. For example, polls show about 5% of U.S. adults now identify as vegetarian and 3% as vegan. These rates may continue growing with greater awareness of health and environmental issues.
What is the evolutionary evidence for humans as omnivores?
There are several evolutionary lines of evidence that point to humans being adapted for an omnivorous diet:
- Fossil evidence shows early hominin species like Australopithecus afarensis regularly consumed meat in addition to plant foods.
- Tool use for hunting large animals occurred early with Homo habilis around 2 million years ago.
- Homo erectus adapted to an omnivorous scavenger lifestyle on the savannah.
- Stone tools for butchering meat became more advanced in Homo sapiens and Neanderthals.
- Isotopic analysis shows Neanderthals derived up to 50% of calories from meat.
Meat was likely a critical calorie and nutrient source that fueled the evolution of larger hominin brains over time. Cooking food also increased digestion and absorption of meat and plant matter.
What evidence is there that humans are anatomically adapted to be omnivores?
Some key anatomical adaptations suggest humans are omnivores:
- Teeth – Humans have biting and tearing incisors and canines alongside grinding molars suited for both meat and plants.
- Jaws and mouth – Human jaws move side-to-side easily for tearing meat but our mouths also finely chew plant matter.
- Saliva – Human saliva contains amylase enzyme to digest carbohydrates from plants.
- Stomach acidity – Humans have relatively strong hydrochloric acid for breaking down meat compared to herbivores but weaker than pure carnivores.
- Intestines – Human small intestines are shorter than herbivores’ to absorb meat proteins quicker but longer than carnivores’.
In summary, humans have a flexible digestive system well-equipped to fully digest and absorb diverse omnivorous foods.
What evidence is there that humans have nutritional adaptions to eating meat?
Here are some ways human biology is adapted to derive key nutrients from meat:
- Humans efficiently metabolize protein and fat from meat – we have enzymes like amylase and lipase to break them down.
- Meat is an excellent source of bioavailable iron, zinc, and vitamin B12 for humans.
- Humans can convert saturated fats and cholesterol from meat into hormones and vitamin D.
- Eating meat may have helped early humans synthesize long-chain fatty acids needed for brain growth.
In short, eating meat allowed our omnivorous ancestors to obtain dense calories, protein, and key nutrients that likely conferred a survival advantage. Humans continue to metabolize and utilize most nutrients from meat effectively.
In conclusion, the standard type of diet for humans is omnivory, which includes significant amounts of both animal and plant foods. Humans are anatomically and biologically adapted for effectively digesting and metabolizing a wide variety of food sources as omnivores. However, modern dietary guidelines generally recommend limiting red meat intake due to potential negative health impacts. Most people only need a moderate amount of animal foods as part of a balanced omnivorous diet.