Herbivores, Carnivores and Omnivores
Today, let us look into the differences between herbivores, carnivores and omnivores when it comes to their nutritional needs and digestive capacities. It may seem unnecessary to you as a topic, but I assure you that’s not necessarily the case – I’ve heard very, very intelligent people say very “surprising” things. So here comes a short lesson in basic biology to refresh your memory, in case you need it:
Herbivores are animals that feed only on plants, in particular grass, leaves and herbs. They have long digestive tracts, with several stomachs (like cows) and/or very long guts (like gorillas), which allow them to ferment large amounts of plant food, including fibers such as cellulose that the human body cannot digest. Since the food they ingest is not very nutrient-dense, they have to eat enormous amounts and spend most of their day chewing and re-chewing. The digestion process takes a long time and the amount of acidity in their stomachs is rather low. Their bellies are usually bloated from all that fermentation activity. It is that fermentation activity that makes nutrients available to the animals that we humans would not be able to assimilate eating the same plants. This includes the important vitamin B12 (see more on that topic below), non-heme iron, and also protein. The greener and fresher the plants they eat, the quicker they ferment and the more nutrition and protein they provide. The dryer and browner the plants, the more cellulose and fiber they contain and the content in protein is lower. The very bacteria that ferment and digest the very hard-to-digest plants then become food themselves and are actually an important source of protein for these large and strong animals – another huge difference to the human digestive system. The teeth of herbivores are broad, apt for grinding up plant matter – not sharp and long as needed in order to kill another animal. Herbivores, like cows, sheep and goats, but also gorillas or elephants, can live 100% on grass and herbs. They actually do not do well on large amounts of grain or legume as fed to them in the industries.
Carnivores are animals that eat mainly other animals, even though some of them, like dogs, might also eat other foods if in need or offered them (these are called “flexible” carnivores). Others are less flexible (like cats) and will get sick if they do not get enough meat or fish. Carnivores have a lot stomach acidity that allows them to digest proteins and even bones with very little chewing. Their digestion tracts are short and the digestion is very quick. They have sharp teeth that allow them to hunt and kill. Examples are cats, dogs, lions and tigers.
Omnivores eat and NEED both plants and animals. They have both sharp and round teeth to eat both meat and plants (modern humans no longer need very sharp teeth because they invented all kinds of tools to kill animals). The level of stomach acidity is moderate and actually also depends on ones Metabolic Type (more or less need for meat). It is high enough to digest meat, but not high enough to digest bones. They also have gut bacteria helping them to break down plant foods, but not to the extent of herbivores. Humans fall into that category, but also chickens or pigs, for example. Eating more nutrient dense foods, and not having to spend all day chewing and fermenting food, is an advantage for us humans, allowing us to free up time and energy for other purposes.
