Is a Vegetarian diet healthier?

by Deb on February 14, 2011


A couple of ground rules first.  Here I am only talking about science, not ethics.  I know a lot of people choose to be vegetarian for ethical reasons.  While science can help inform ethical questions, only your own conscience can decide where you stand, so good luck with that.  Secondly, this is not about the environment since it’s a blog not a book.  There will be an environmental post later down the track, but as the title suggests I’m only looking at direct health here.

There seems to be an image in popular culture that vegetarian diets are healthier.  I think it probably started because we all know that vegetables are good for us, and vegetarians have it right there in the name, right?  So it must be good for you, right?

I like mystery novels but I don’t think it’s a good way of constructing an argument, so I’ll tell you right up front what the answer is – a solid sometimes.  Because you see it’s completely the wrong question.

Labelling a diet as ‘vegetarian’ sounds as if it’s well defined, but really it tells you nothing about what is in it, only what isn’t there.  Chips are vegetarian.  So are sugar, many biscuits, icecream and chocolate if you include dairy products.  All sorts of oils and fats are vegetarian.  Caramel toffee, midori slushies, coke.  It is possible to be extremely unhealthy without touching a speck of meat – some teenage girls do it all the time.  To ask if it is healthy to include or exclude a single ingredient, in the absence of allergies or intolerances, is simplistic and even a little ridiculous, because we need a wide range of nutrients and eat a wide range of foods.

Rather than ‘Is a vegetarian diet healthier?’  the question really should be ‘Do humans need meat?’


Humans have evolved as omnivores.  In a very real sense, you are sitting here at your computer because your ancestors ate meat.  During pregnancy and childhood we grow relatively enormous brains and they need large amounts of high-quality protein to develop.  Your brain is about three times the size of a chimp’s and they are bigger than you.  On the savannah or wooded riverine valleys, the best sources of protein are animal products – meat, eggs, insects or fish.  This isn’t to say our early ancestors were hunters, they could have got what they needed quite well through scavenging or catching small animals like insects and lizards, which still provided a lot of protein for hunter gatherers in historic times.

We can tell that humans were omnivores because of how our bodies have changed, compared with our mainly vegetarian cousins.  I say ‘mainly vegetarian’ because did you realise that chimps, bonobos and baboons enjoy meat?  These primates are fairly aggressive and are known to hunt as packs.  So there were probably already some omnivorous leanings when our lineage split from the other apes.  Apart from our brains and our legs, the big differences between humans and other primates are in our gut and teeth.

Plants are difficult to digest and herbivores tend to have complicated guts – think of cows with their four stomachs.  Meat, however, is easy to digest and carnivore guts are relatively short, simple tubes.  Our gut obviously started as a herbivorous gut, but our caecum (end of the large intestine where the appendix is), colon and stomach have been greatly reduced.  We do not by any means have a carnivore gut, but we have definitely adapted to include animal proteins in a mixed diet.

Chimp, afarensis, human teeth

Plants are also difficult to chew, especially the tough parts such as leaves, shoots, seeds and roots.  Herbivores have large grinding molar teeth to break them down.  Some early hominid cousins, the robust Australopithecines, appear to have developed in a herbivorous direction and over time developed larger and larger teeth.  At the same time, the hominids in our own lineage were reducing our molars and premolars so we no longer had the ape-like snout.  We also drastically reduced the size of the muscles used in chewing which changed the shape of the skull, as the various crests and ridges of bone used to anchor the large chewing muscles were no longer needed.

Human and Chimp skulls

The chimp snout is caused by the large teeth, and the ridges above the eyes, at the top and back of the head are to anchor large muscles.

Another indication of human omnivory comes from our metabolism, in particular Vitamin B12.  This vitamin is only produced by bacteria and some algae.  Herbivorous animals get it from the bacteria in their gut, however humans only have these bacteria in their colon where it cannot be absorbed.  The only natural source for humans is animal products.

This is not to say that humans should be almost carnivorous or even eat a lot of meat – most modern Western diets include far more meat than we evolved with.  But there have historically been groups that have been almost carnivorous, such as the Inuit.

Our ancestors needed meat, do we?

Again the quick answer: no.  We evolved the need for meat back when we needed a high quality protein and calorie source and didn’t have the ability to process or grow food.  Today we do have those abilities.  So it is possible to be healthy without eating meat, as long as you have good sources of the proteins and nutrients meat provides.  Beans and legumes are excellent sources of vegetable protein and different vegetables will help with iron, especially if combined with vitamin C.  Vegetarians who use milk and/or eggs will generally get enough vitamin B12, but strict vegans need an artificial supplement.  It’s also important to remember that children have different nutritional needs to adults – they are the ones growing that large brain and body and being hyperactively active.  It is possible for modern children to be healthy vegetarians, but it does need to be researched to check they are getting the right nutrients.  As every diet should be.

Downsides to meat

So are there downsides to meat?  This time it’s a qualified, iffy maybe.  Inuit people managed just fine, but I don’t think many of us will be able to emulate them – there aren’t that many seals around.  There are possible problems with processed meats such as bacon and sausages – but is that the meat or the other chemicals and fats involved?  There are some analyses that have found red meat is fine and others that recommend reducing it.  What it comes down to is that diet is very, very difficult to study.  Humans are not like rats who can be fed whatever you want, they have a nasty tendency to not remember what they ate or change their eating habits when they are being watched.  Overall it seems that meat is probably not a problem in and of itself, but it is a problem if it is stopping you from eating the other vegetable nutrients your body needs.

Is a vegetarian diet healthier?

Any diet that involves thought and a long term effort to provide your body all the nutrients it needs will probably be healthy.  Fad diets are unhealthy.  Starvation is very unhealthy.  Moderation, a broad range of foods and listening to your body so you learn which foods make you feel good rather than a quick taste hit or convenience will probably give you a healthy diet. In spite of all the doom and gloom we are living longer today than ever before.

Some interesting reading

Related Posts with Thumbnails

Enjoy this article? Subscribe to the weekly newsletter to hear about them all. Or grab my RSS feed

{ 12 comments… read them below or add one }

Gillian February 14, 2011 at 7:50 am

How nice to read a piece on this subject without huge mounts of emotive language to make a point and sway opinion. You are absolutely right, the health issue is a separate one to the ethics, where they overlap is how we produce that meat and where we as the “intelligent” species have to decide what we are willing to accept. I gave up eating meat in the UK when the cause of BSE was first identified as a personal protest at what was commercially being fed to many farm animals and because organic meat was so expensive – I just dropped the meat entirely. The worst thing is that most people don’t know the manner in which much of our food is produced, if they did they would perhaps buy differently – eggs is an example that immediately comes to mind.


Deb February 14, 2011 at 8:53 am

We’re lucky that we have our own free range chickens and have so many eggs we have to give them away! Eggs are definitely problematical in deciding what is the most ethical way of producing them. Many people don’t realise that barn eggs are actually ranked above free range eggs by various animal organisations, because of the risks to free range chickens. Having lost three of ours to dogs, I can definitely understand that.


Marita February 14, 2011 at 11:08 am

Fantastic post. My 7yo is in the on again stage of being vegetarian. For her the ethical issue is her prime motivator, although I suspect she has sensory issues related to the texture of meat.

We’ve been looking at a variety of diet options to increase her iron intake as last blood test showed she has low iron levels.
Marita´s latest amazing offering ..Running from the PoliceMy Profile


Anonymous March 15, 2012 at 3:07 am

As a vegetarian, I can personally encourage her to continue. However, I would check to see if she is on the Autism Spectrum. As, it is very common for people with Autism to have a certain way, their food must feel.


Deb March 16, 2012 at 11:08 am

Thanks for the lovely suggestion. Marita’s daughter is on the spectrum, she writes about it at Stuff With Thing.


Veggie Mama February 14, 2011 at 10:06 pm

I do appreciate a well-balanced argument! I think a diet with or without meat in reasonable quantities can be healthy. And also unhealthy! There’s always extremes 🙂


Deb February 14, 2011 at 10:37 pm

Exactly! Meat is only one tiny part of a diet, it’s the diet as a whole plus exercise and lifestyle that determines if it’s healthy or not.


amandab February 17, 2011 at 8:37 pm

As I watch more and more of my food coming from plant sources I found this very interesting and timely.

Whilst I have cut down my own meat consumption I haven’t cut down what I put on anyone else’s plate though, it’s not my choice to make.

I have noticed that our processed “cold” meats aren’t getting eaten though. Everyone seems to prefer cheese to meat for the lunch. I feel a bit better about that.


PM November 11, 2011 at 11:57 am

All I know is that now that I’m a vegetarian, I look younger than I did when I was in my 30’s. I’m now in my mid 40’s. I was told I look like a teenager. I have also become more peaceful with myself and the world. Could it be the vibration of the food? They say that when you eat meat, your actually taking on the cell memory of the animal that was slaughtered. That’s scary!


Deb November 11, 2011 at 3:08 pm

I work with teenagers. If you are in your mid 40s, how is that a compliment?

The point of this post is that it is silly to the point of ridiculousness to judge a diet on the presence or absence of one food. Humans need a broad range of nutrients and the best way to ensure you get these is to eat a broad range of foods. If you choose not to eat meat then there are health consequences you need to be aware of and allow for, but so long as you do that you can be healthy on either a vegetarian or a meat eating diet. If you have developed a healthy diet that is working for you and you are enjoying, that’s fantastic.

Anyone eating a wide range of healthy foods will generally have a healthy diet – whether or not that includes meat. And anyone eating too much fat and sugar will have problems, whether it is in meat or potato chips.

Ethical considerations were not part of this post at all, they are a personal question. However I have no idea what you are talking about with vibration of food – most food is remarkably still because it’s dead, and that’s whether it started as a plant or animal.

Again, what do you mean by cell memory? Do you mean the DNA (which is just a chemical when it isn’t in a cell) which is passed on to other cells when it splits? Do you mean some of the other chemical reactions inside the cell which stop when it dies? What is cell memory?

And you do realise that plants have cells as well? So if you eat flour, are you taking on the cell memory of the grain of wheat that was reaped, stripped and crushed? Being seeds, grains are one of the few foods that continue to live after they are picked and the cells would survive up until they are ripped to shreds during milling. That actually sounds far more terrifying than a quick death.


sanchomama April 13, 2012 at 12:29 pm

You know what Deb, you’re the only one who left a patronizing and antagonistic comment. It’s been an intelligent conversation about a controversial topic. What do you have to pick on PM for?


Deb April 13, 2012 at 5:21 pm

Antagonising and patronising? Actually what I did was take a spammer seriously. I object to my blog and my readers being insulted and used, PM’s is the comment that is antagonistic. For some weird reason our society thinks it’s ok to insult people and doesn’t like it when the insults are called.

Why I consider ‘PM’ to be a spammer:
– It turned up in my spam folder, and Akismet has a pretty good track record. I actually gave PM the benefit of the doubt.
– The comment has little or nothing to do with the post.
– The comment has nothing to do with the previous comments.
– It’s about ethics, in spite of the fact that the second sentence of the post specifically says that ethics is a separate issue.
– It’s anonymous. While there can be very useful and genuine anonymous comments like the one above, add it to the others and it adds to the spam suspicion. PM could be a person or a bot set up by a vegetarian group – I’ve had ones from chiropractors, and as you say it’s a passionate issue so it’s plausible.
– It’s ridiculous. Someone in their mid 40s was told they look like a teenager? Look around you – the differences between teenagers and 40 year olds are not about diet and everything about growth, maturity and deportment.

Do you seriously consider this to be an intelligent contribution to the discussion? That sort of over the top claim is a sign of propagandising, not of serious engagement. To use your own words, I consider it patronising for someone to expect me to swallow a statement like that. That undoubtedly influenced the way I replied.

If you look at my reply, you’ll see that I’ve patiently clarified what the post was about, and then I’ve taken PM’s claims seriously and asked he/she/it to explain them. I’ll openly admit I didn’t expect a reply, most of these sorts of comments are drive-bys by people just wanting to scatter gun their own message on other people’s work without taking the time to build up a platform for themselves.

We all know what people look like, and I say again – how is looking like a teenager a compliment for a mature adult? Perhaps you could explain, since I would take it as an insult or at least a very strange thing to say. Asking a question is not patronising, it’s a sign I don’t understand. It could be antagonistic to not politely let the lie past, but I don’t see why I should be polite to people who are lying to me.

I’ve devoted a couple of paragraphs to clarifying the point of the post. Re-reading them, I honestly can’t see them as patronising or antagonistic. They might be short because I’m trying to summarise the whole post, but personally I’m happy with the way they turned out. I’ve even sincerely congratulated he/she/it on finding a healthy diet that is working for them.

The next paragraph is the only bit of my comment I would agree is patronising, because I really am confused by people thinking that dead things are moving. I would hope we all know what vibration means, therefore I’m completely serious in asking what on earth that statement means. How does food vibrate? It is so weird it sounds a lot like someone taking the mickey, don’t you think? Perhaps I shouldn’t have lost my patience with a (possible) commenter, but when they haven’t engaged with the post or comments, haven’t read the clear disclaimer, and are using my work to push their own agenda, how much patience do they deserve?

Then I have some completely serious questions about cell memory, trying to work out what he/she/it means. Far from being antagonistic I’ve even given suggestions about what I think it might mean, in case PM is a human not a bot and wants to clarify the way they talk to others so they can be understood (and not be sent to spam).

The last paragraph is again completely serious. Asking someone if they realise plants have cells would be patronising if you assume that is basic knowledge. But the statement is so illogical and the previous statements about vibrations and cell memory show so little biological knowledge that I didn’t think it was safe to make that assumption. If I’d wanted to be patronising I would have phrased it slightly differently – ‘You do realise that plants have cells too, don’t you?’ It’s a slight change, but I believe the way I wrote it is more neutral, an attempt to give someone an out and admit to a mistake rather than ignorance. It’s difficult communicating with an anonymous, ambiguous set of initials – if I assume knowledge then I’m treating them as if they are lazy or illogical, if I assume ignorance then I’m treating them as if they are ignorant. I can’t actually see a good outcome here so I did the best I could.

If animals have ‘cell memory,’ whatever that may happen to be, then plants do as well. The things that are done to process plant cells are at least as bad as what is done to animal cells. If animal ‘cell memories’ are scary, aren’t the cell memories from plants? When you make a fruit smoothie do the cells of the banana make a memory and pass it on? Wouldn’t being picked and crushed be a bad memory? Exploring the consequences of someone’s statement is not antagonistic, it’s how we learn. It’s testing whether the idea is a useful hypothesis. If you are going to base your diet on an idea, don’t you want to test it out first to see if it is plausible and what the consequences would be?

I put a lot of time and effort into this blog because I am passionate about a message – that we can all be involved in science and use it to understand our world. Part of that is making a habit of questioning what ‘they say’, which is exactly what I am trying to do in this post. I resent it when someone/thing tries to hitch a ride on my work to push an unquestioning agenda. It is an insult to me and to my readers to use us in that way. I had three choices – leave it in the spam folder, publish it and go against the whole point of the blog and this post, or try to use it as a teaching moment.

If that didn’t work for you, then I’ve missed the mark. But questioning is not patronising and it is not antagonistic.


Leave a Comment

CommentLuv badge

Notify me of followup comments via e-mail. You can also subscribe without commenting.

Previous post:

Next post: