My understanding is that the proper calculation for this is not x-times-body length, but x-times-trunk length.  Our intestines are about 9-times trunk length.  This sometimes gets mis-stated as body length, but trunk length is how it's actually calculated for mammals.

As for the rest.  The reality is that each side of this debate can point to different traits to prove their point.  It seems to me that if you add them up, however, about 2/3rds of our traits tend towards the herbivorous side of the spectrum, for what that's worth.  No definition is perfect, or without exceptions, and perhaps we're an exception too.

Or perhaps not.  I think it's broadly accepted that we evolved eating mostly fruit (back when fruits were kind of halfway between a modern fruit and vegetable).  That's perhaps one of the reasons why we may see colours, whereas many carnivores and omnivores cannot perceive colour.

I think the most accepted modern thinking is that we can eat both plants and animals, but that plants are mandatory or that (short of supplementation) we'll get scurvy and die.  Eating animals is optional, every nutrient available from an animal source is also available from a plant source (yes, even B12).  Broadly accepted modern thinking appears to be that we've been eating plants longer than we've been eating animals and, as such, we're better adapted to eating plants than we are animals.  Finally, the preponderence of the best evidence is that the growth in chronic disease is from the increasing amounts of animal products and refined foods in our diet.

Government health agencies that remove research funded by vested interests (whether it's a dairy marketing board, or the rice lobby, or what have you), are suggesting people should focus on whole plant foods and reduce their meat/dairy/egg consumption (such as the recent draft Canadian government health guidelines that raised beans above meat for protein, etc.).  The vested interest research is all over the place, but the independent research is coming up with an extremely consistent message.

I've been a vegan for 3 months now for health benefit and I don't agree with all of the chemicals/drugs pumped into the animals which we then eat....it's been amazing the food is so much more tastier. Would literally never go back.

possibly the stupidest thing I have read on this site to date...

You're incorrect.  Almost no health agency on the planet suggests any requirement for any amount of animal products for optimal health.  So that's false.  Animals get their nutrients from plants, and then we eat the animals, so it's just a question of whether you go to the source or filter your nutrients through animals.  It's a falsehood that we require animal products for health.  And we lack a lot of biological elements common to omnivores, such as we lack the ability to get rid of cholesterol.  Dogs can.  Wolves can.  We cannot.

That's a big deal.  Researchers started to notice a strong correlation between heart disease and impotence.  And then they realized it wasn't just a correlation, they were the same disease.  In both cases, cholesterol plaque was clogging up the body.  In the case of heart disease it was the arteries leading to the heart.  In the case of impotence, it was cholesterol plaque clogging up the penile artery.  (Yes, emotional factors often come into play with impotence too, but it's frequently an initial 'failure to perform' that kicks off the emotional spiral.)  This was on top of the previously identified correlation between heart and stroke, and a new correlation subsequently observed with several previously unexplained neurological diseases.  It turns out all these diseases were the same disease, cholesterol plaque clogging up different parts of the body.  They have tried to give these diseases to obligate omnivores in controlled conditions and failed, because their bodies are successful at getting rid of the excess cholesterol.

Humans traditionally ate very little cholesterol in our early evolution, as in the cradle of civilization in Africa we largely ate plants.  Our bodies make cholesterol, but rarely in excess so a mechanism to get rid of it wasn't necessary.  Similarly, we once had a gene to produce vitamin C, but we were eating so many plant foods rich in vitamin C that the gene deactivated in humans hundreds of thousands of years ago.

Now vested interests are trying to convince us that eating cholesterol has no bearing on heart disease, and funding science that tries to come to that conclusion.  But they're useful poor scientific method and these studies are rarely submitted to peer review and are being roundly ignored by most public health agencies.  The preponderence of the best and most independent science continues to tell us that eating cholesterol raises cholesterol in the body, and that increases the odds of a raft of chronic diseases.

Pair that all up with the fact that there's no disease that's caused by a lack of meat in the diet, like there is for the lack of sufficient plant foods in the diet (scurvy), and the conclusion seems pretty apparent to me.  Eating a broad spectrum of whole plant foods is optimal for human health.

(Citations for everything I've said before has either been previously provided by me, or is available upon request for any point you'd like more info on.)

You just not have been paying attention. I've said MUCH stupider!

*Edit*

I'll explain, though. I was trying to lose weight in a short amount of time so I totally eliminated certain things from my diet until I reached my goal. Basically a weight loss diet of my own design.

I felt more energetic but I think I lost muscle mass as well.

Interesting similarities.  Not only do we both live in Canada, but I'm also a cyclist.  :)

There's a bit of a myth to aging.  The idea that we inevitably get frail as we age is being challenged.  As we look at the Okinawans, the Tarahumara, the Adventist vegetarians, etc., we're seeing these highly plant-based populations are also unusually vibrant in old age.  One recent study of 4200 autopsies found that not one of them died "of old age", all of them died of disease.  Even people who lived to be over 100 clearly died of a disease.  As we age our defences against disease drop, but diet and lifestyle choices can protect against that.  A plant-based diet reduces systemic inflammation in the body (vs. animal products which promote inflammation).  An active lifestyle can keep the body more supple (the "use it or lose it" philosophy has a lot of truth in it).  If you eat anti-inflammatory foods and stay active, you significantly improve your odds of being vibrant into your 90s.

I'm going to just assume you're taking statistics out of context and lean on those until your thyroids give up and you're forced to adopt meat into your diet. "Only vegans have healthy BMI"? Really? Let's look at the rest of the statistics: how many of those people are active? How many don't have time to exercise because of life events? How many live in countries where $1 burgers are a thing? Vegans have a healthy BMI because it's a diet that lacks fat almost entirely, so there's less need to exercise. But, you know, keep drawing whatever conclusions you want. Fact of the matter is veganism is a diet that supports inactive lifestyles, which is what the world has very rapidly become over the last thirty years.

The point on fruits and vegetables wasn't a "oh, they have Mercury" comment. It was a "nothing is healthy when you overanalyze everything" comment. Which is true unless you grow your own food in soil you received from a place that industrial man has never touched. But you know, keep it up with the out of context shenanigans.

B12 again, let me spell it out for you: omnivores don't care where it comes from. And they get it. Grats to them. Vegans do, and most B12 supplements are animal-based. No, I don't have a citation, because I don't have time to troll the internet for it. All I have is the word of a real dietician. Take it how you want, but I'll be laughing all the way to the bank when you use B12 supplements that have animal biproducts in it.

Plant-based omegas are ALA, which have to be converted into EPA or DHA to be used. The conversion rates for those are 21% and below, even lower for men. So no, they're not readily absorbed- like most plant nutrients, everything you get from flax and algae have to be converted into something else before your body can take it. Th e reason it's more readily absorbed by fish meat is because ]it was already processed by the fish. It'st kind of silly how you pretty much already pointed out the flaw in vegan logic, but acted like it was nothing.

Most vegans are super unhealthy because they have no idea how to be vegan. You can throw citations at me all you want, but you are, again, forgetting context. Every vegan from here to Timbuktu knows there are vitamin deficiencies in their diet of choice because everyone tells them that as an attempt to get them to deny the punch they drank. So they take supplements haphazardly, usually resulting in the dimmer ones taking animal biproducts by mistake (always a good laugh when I used to work at a grocer). They're not healthier because of they're diet, they're just more loaded down with nutrients as a direct result of people warning them about it. If that study was for real, it'd only be showing people who don't take multivitamin supplements.

((Skipping a response to these next paragraphs because I don't care about your "where are your citations" rant))

You know what's more dangerous than lying? Giving cherry-picked evidence and ignoring context to make a point. Vegans are, statistically, the most conscious people when it comes  to their diets. So when you give numbers of vegans versus normal people, you kindly leave out that were comparing nutritionally-minded people to lazy slobs, right? I would like to see some more accurate numbers. I dunno, maybe we can put  dieticians against each other instead of average Joe's against "does this have milk or eggs" nutters. And in the face of all your demands for citations, you have still never addressed the fact that mankind evolved to eat meat. Should we be eating as much meat as we do now? Good lord, no. The meat industry is ruining people at a young age with excess meat consumption. That's something I'm sure we can agree on, but removing meat entirely from your diet is a risky maneuver that people should treat with the utmost care. No, it's not the end of the world if you go vegan. Yes, you can be a healthy vegan if you're devoted enough (as long as your thyroids aren't shit). But eating meat would be better for you in the long run if you learn self control.

Paleo and Ketone diets that limit carbohydrates have been more successful for weight loss, provide adequate protein intakes and meet mineral and vitamin requirements.
Vegetarian/Vegan diets lack calories and fail to meet mineral, vitamin and protein requirements. There is too much sugar in fruit and eating too much fruit is not good for health. Bread, rice, pasta, potatoes and starch carbohydrates are well known for making people overweight and contributing towards the obesity epidemic.
Vegetarian/Vegan diet is a political decision based on being an environmentalists wanting to save animals by not eating animals. There are no health benefits from following a Vegan/Vegetarian diet due to the lack of protein, deficiencies in minerals/vitamins.

You're giving false information on this. Humans require nutrients that only come from meat and animal products. End of story. To live a vegan or vegetarian lifestyle, supplements are required if they want to remain "healthy" by the standards of actual doctors. If not they'll eventually have short term or permanent health problems ranging from muscle aches to dementia to different disorders. People should be eating meat and plants daily.  Science recommends that humans take in B12 daily which only comes from meat and animal products.... 

You are 100% incorrect. You do realise 32% of the worlds population is vegan or vegetarian?? cows milk/dairy products have been linked to cancer in over 1000's of different research. The cancer council is sponsored by the dairy industry, KFC list goes on. They literally send them truck loads of money to keep it hush hush. Do your own research. Clearly you are just followering orders from a doctor.....God bless you.