Subtitles section Play video Print subtitles These days, it seems like everyone has an opinion on whether eating meat is good or bad for you. After all, it's thought that meat is what helped you humans evolve into, well, humans. Still, vegetarians swear by tofu, veggie burgers and whatever tempeh is, but can your body function properly without meat? Let's find out. Humans first started eating meat about two and a half million years ago. But before then, they were eating lots of fruits, leaves, flowers and roots, but it's believed that the addition of animal protein and the accompanying calories helped their early brains and bodies evolve and grow larger. But nowadays, is meat really that necessary? Meat is packed full of nutrients like protein, iron, calcium, and vitamins D and B12, that are all super important to keep your body functioning properly. Deficiencies in these areas can lead to things like increased risks of developing certain cancers and autoimmune diseases, decreased energy levels, headaches and loss of muscle mass, just to name a few. But you apparently don't really need meat. Most vegetarians can keep those levels in check with lots of beans, leafy green veggies, soy, dairy, nutritional yeast, and whole grains. Dietary supplements can also come in handy, too, and making sure your body is getting everything it needs. Cutting out meat from your diet will have some effects on other aspects of your health. One of the first things that'll happen is the bacteria in your gut will change to account for a new type of diet, which may result in a little bloating but nothing serious. As time goes on, you'll actually feel happier, more energetic, and healthier all around. You'll probably lose some weight too. It's found that just cutting out meat and changing nothing else can cause people to lose about four or five kilograms. And your risk of developing heart disease drops pretty significantly, as much as 25%. Plus, processed meats have recently been classified as carcinogens by the World Health Organization, meaning they're known to cause cancer. If you cut those and other types of meat out, your risk of getting cancer drops. While almost everyone's body is built to handle a moderate amount of meat, some people suffer from meat allergies. Which I know that some of you might sound made up, but the science says it's a real problem! These allergies can be pretty serious and come from a few sources. First, when your body becomes overly sensitive to meat, maybe from not eating it for ten years, your body considers it a threat. So, when you eat meat, your system releases huge amounts of histamine to try to protect you. This influx of histamine can cause a huge array of reactions, ranging from hives, to eyelid swelling, to abdominal, respiratory and cardiovascular distress. All from a little bit of meat! In some extreme cases, you may experience a life-threatening reaction called anaphylaxis, causing your airways to close up. Another, quite unusual, source of meat allergies is the Lone Star tick. One bite from this insect can rewire someone's immune system and cause them to develop an allergy to red meat! Whether someone stops eating meat voluntarily or because of an allergy, it can have a big impact on their health and overall well being. Statistics vary, but it's thought that about 3% of Americans are vegetarians. Are you one of them? Do you feel different not eating meat? Let us know in the comment section below.