By Marika Sboros

Today, Foodmed launches Vital Signs, an occasional series of Q&A interviews with those forging new paths in nutrition science globally. Along with top doctors and scientists, we also feature ordinary mortals. These are the brave lay people who make up the wisdom of the crowds. They usher in bottom-up change from eminence-based to genuinely evidence-based medicine.

First up is Canadian-born US-based carnivore and artificial intelligence hacker L Amber O’Hearn who lives in Colorado. O’Hearn is a data scientist by profession. She is also a singer, writer, mathematician who has been researching and experimenting with ketogenic and evolution-based diets since 1997.

O’Hearn has put her day job aside to focus on researching, writing, and speaking about nutrition. She is an author at The Ketogenic Diet For Health and Empirica and has no qualms about going carnivore. And yes, she eats some of her meat meals raw. And no, she’s not aggressive as a result of being a dedicated carnivore. Here’s what drives her dietary habits:

Marika Sboros: What was your earliest ambition?

L Amber O’Hearn: I wanted to be a singer, writer and mathematician. It never occurred to me that it’s hard to be all those things at the same time.

Which one did you ditch first?

Singing, though I’m not sure why. But I carried on singing in the kitchen and the shower.

But I hear that you’re singing again?

Yes. I’m back-up singer in Niwot’s Curse. It’s a punk rock band.

Nice name. Where does it come from? 

The name of an Indian chief and a town outside Boulder. Niwot means left-handed. Chief Niwot is supposed to have said that there’s a curse on the area. Many people will come here and won’t want to leave but their staying will spoil the area.

You continued with math?

Yes, I started studying mathematics at the University of Waterloo in Ontario. After the second year, I switched into a Russian language program.

Why Russian? 

A lucky accident. I’ve always loved languages. I really wanted to learn Japanese but the course was full. So, I took Russian instead and instantly fell in love with it.

What made you go into computer science?

A circuitous route. At first, I had no interest in computer science. I had to take theoretical computer science when I was doing a math degree.  I realised that it is mathematics and also didn’t want to be a programmer by profession. Realy, I just wanted to study the theoretical aspects of programming and computer science. And I found that I was interested. I decided to study computational linguistics. It felt like a beautiful marriage of several of my interests.

You wanted to become an academic. Why didn’t you?

Family intervened – marriage, children. I needed a job and decided to try programming professionally. I became a data scientist.

You went to Hacker School in the summer of 2014. Are you a hacker?

Yes, but in the computer science community, we understand that word differently. It was originally a term of admiration for someone who really cares about how things work, and can come up with elegant solutions to problems. You have to love and understand computer science to get that nickname. Hacker School is a  unique place idea that attracts people who love computer science. They set their own goals and fulfill them in each other’s company.

What makes a good hacker?

One who has an awe for the machine and the power of what people can do and uses that to really understand what’s going on at a deep level.

And a bad hacker?

Bad hacker is an oxymoron, you’re either good at it and a hacker or you’re not. We distinguish between black and white hat hackers. White hat hackers want to make the world a better place. Black hat hackers are into criminal activity. They want to manipulate, harm or steal.

That’s all far from your current field of interest: researching and writing on optimum nutrition to treat and prevent serious disease. In particular, your focus is low-carb, high-fat (LCHF) and ketogenic diets. Critics may say you should stick to what you know best: computer science. Do they have a point? 

It’s easy to give glib answers about why I’m well suited for it. The human body is a complex system. Having studied mathematics, I have special training in understanding complex systems. But that’s not why I got into writing about LCHF and ketogenic diets.

One of L Amber O’Hearn’s favourite raw meals

So, why did you?

If you look at the writing on my website, I choose topics where there is lack of consensus even among advocates of ketogenic diets. People were disagreeing and saying things about the science that didn’t make sense to me. When that happens, I feel a need to dig.

What did you dig up?

The medical and dietetic communities have been hostile to low-carb for a very long time. I think it’s because they tell and believe an unnatural story about ketosis. They say it’s not natural and that it mimics starvation. In that case, you naturally tend to see danger and problems wherever you look. Combine that with animal fat and meat—they have the mistaken idea that fat is bad. To get into a ketogenic state you have to eat a lot of fat. That scares people. (Editor’s note: for more on ignorance about ketogenic diets, listen to O’Hearn’s recent Ancestral Health Society talk at the University of Washington.)

Are those fears founded in any way?

Not significantly. If you look at nutrition through a different lens, how it naturally arose through evolution, you can more easily see the benefits of it. To me, it’s the story about what ketosis is that is affecting our scientific interpretations, and that makes it a language problem as much as a systems problem.

When did you start researching nutrition?

My interest goes back at least 20 years. I read Protein Power by Dr Michael Eades and Dr Mary Dan Eades. His ideas were so different and his book full of references, I could see for myself what the science was saying. That has been bubbling in my brain’s back burner for a long time.

You make conventional dietitians green around the gills. Why?

I find that the dietetics profession generally has a pessimistic view of disease, health and healing. I don’t see a lot of critical thinking going on. And I have no problem with their criticism of my work but they should judge it on its own merit, not my credentials. Otherwise, it’s not constructive. I don’t think that science supports what orthodox dietitians learn during their training.

They aren’t taught how to evaluate evidence properly. And when I ask for evidence, they bring epidemiological evidence. That’s weak evidence, good mostly for generating hypotheses. I find it hard to have a productive conversation with dietitians when their idea of what constitutes evidence differs from mine.

Prof Tim Noakes cited your research as evidence during his trial in South Africa. What prompted the research?

I noticed that even textbooks about newborn infants acknowledge that babies are in ketosis when breastfeeding. I saw that as strong confirmation that ketosis is a natural state not just for adults but also for infants and growing children. Following that, I found the work of (Canadian professor) Stephen Cunnane. He refers to other research showing that the brain doesn’t just use ketone bodies for fuel.

What’s so great about ketones?

Ketone bodies are the brain’s building blocks because they cross the blood-brain barrier. Once I saw that connection, it made sense. Many mammals, or most, are in ketosis when they are suckling. I used to think that the main reason they stopped being in ketosis was because their natural post-weaning diet prevented it. But then, coincidentally, brain growth stops. In many species, such as rodents, they are not in ketosis after weaning but their brains have grown to full capacity, but human brains continue to grow long past weaning, and human children will stay in ketosis as long as you don’t introduce carbs into the diet.

This is not the case in other carnivore species. Interestingly, the natural diet of dogs and cats has no carbs but they’re not in ketosis. Just having only meat is not enough. They need caloric or protein restriction to get into ketosis. As part of my research, I spoke to people at the Keto Pet Sanctuary. They are treating cancer in dogs by keeping them in ketosis. That involves caloric and protein restriction and feeding them MCT oil.  So, I interpret this as evidence that ketosis is a natural state for human children past weaning because it facilitates brain growth, and that is why we stay in ketosis past weaning if carbs are kept low, unlike other species.

What’s an optimal weaning diet for infants?

Once they stop breastfeeding, the best source of brain nutrients are animal sources. Some of the nutrients infants need you just can’t get in plants or can’t get easily. So, meat is essential. It’s not just about low-carb foods but also getting enough protein. The main consideration is that if you feed infants something that is high enough in carbs to prevent ketosis, you are displacing a healthier food. You don’t need to fear that because you take rice or other grain or cereal away, that infants will be in ketosis. It’s okay for them to be in ketosis. When they sleep, they will wake in ketosis anyway as long as there is a period between carb doses

Click here to read: Real beef dietitians have with Noakes 


You have “graduated” from LCHF to going full-scale carnivore. When and why? 

I was a vegetarian for many years and even vegan at one point, but I was overweight and not healthy. Once I read Protein Power, I found the nutrition advice logical and persuasive. I’ve been eating low-carb ever since. Initially, I lost 30lbs. But after a few years maintaining that, I wasn’t able to maintain all of the weight loss. Perhaps it was from pregnancies, getting older, or the anti-depressant medication I was on.  At one stage before my last pregnancy, I weighed over 195 lbs. I don’t know exactly how much; I didn’t even want to look at the scale.

Apart from losing 60lbs by going meat only, any other benefits since becoming a carnivore?

At the end of 2008, I heard about people benefiting from eating only meat and wanted to give it a try. My only motivation at the time was weight loss. But it very quickly became apparent that it had a positive effect on my mood. I had been on anti-depressants since 1993 aged 20. Doctors diagnosed major depressive disorder. Then in my early 30s, they diagnosed bipolar type 2. That diagnosis was a relief. I thought it explained why the medication I was on for 15 years hadn’t worked well. But the new meds also didn’t work.

Some might say it was the placebo effect?

I had grown to distrust my own evaluation of my mental state. But even my husband said that my mood was more significantly improved and more stable than ever since I went carnivore. That was in early 2009.

You have three sons, aged 16, 13 and seven. Is there a carnivore among them?

We have had a low-carb household for years. It has become more meat-centric since I found my own benefit.  However, I don’t force them to eat the way I would prefer. That’s bound to fail with teenagers. They will want to experiment and find out for themselves. They don’t want to feel left out or that others think they are different.I’m currently the only dedicated carnivore. So, I give them what’s healthy at home and also teach them ideas on how to evaluate nutritional science. And then they make their own decisions out in the world.

Vegetarians – and vegans especially –  often say that meat eaters are more aggressive. They even suggest that the carnivore is prone to violence. When did you last punch someone?

Never, even as a vegetarian. That accusation is an inconsistency from the vegetarian community. They like to say that carnivores are more aggressive but also have a lower sex drive. That makes no sense because it’s like saying we have too much testosterone driving aggression and too little for libido.  So, which is it? I don’t like to pick on other people’s dietary habits. However, I don’t hear any carnivore or carnivorous groups having much militant activism about their diet in the same way as vegetarians and vegans. Attributing causality is complex. If I try to understand the vegan position, I think they call us violent because they equate eating animals with murdering people. I think that’s inappropriate as a comparison.

Click here to read:  Medical evangelism: a cover for plant-based dietary advice?


How do you start your day?

With something unrelated to food. I write in my journal. I find it an effective way of getting in touch with the day. And I have coffee, black, not “bulletproof” (with butter, cream and/or MCT oil). My first meal is usually not till 11 am or noon.

What are the staples of your diet?

I have a few basic staples that I eat for my meals whether it’s the first or second meal of the day. I usually have ground beef or steak or eggs, pork, fish chicken. And I do eat dairy but only very occasionally. I notice that it affects my weight – but not mood, as far as I can tell.

What are fat sources? 

I eat fatty cuts of meat, sometimes I will augment that with fat I have collected, such as tallow or lard. I respond to my hunger. If I feel I need more fat, I eat more fat. I don’t sweat it too much.

What’s your percentage protein intake?

I haven’t measured it for a long time but it generally comes out at 20-35% of my calories. And mostly 65- 80% fat.

Do you ever worry about your cholesterol levels and all that saturated fat clogging your arteries?

Never. My vascular system isn’t a drain pipe.

Any physical side effects, such as bad breath and constipation?

I know what you mean. When you first enter ketosis, there can be an acetone smell on your breath. No one around me has noticed – or they’re too polite to say so. Some might find it offensive, others don’t. It doesn’t last. I don’t have a problem with constipation. That’s another myth vegetarians and vegans seem to dispense to knock a low-carb diet or anyone who is a carnivore. A high-fat diet prevents constipation.

Can you imagine not being a carnivore?

No, why?

What’s the least healthy thing you do?

For the last couple of years, I reintroduced alcohol into my diet. I have an occasional wine or scotch. I don’t think it’s particularly healthy but as long as it’s genuinely moderate, I don’t think it’s much of a problem.

Have you had mentors in life?

Yes, I’ve been very lucky to have a lot of people who have given me time and advice. One was my advisor during computer linguistics, Prof Graeme Hirst. He was exceedingly kind and always believed in me.

Ever read a book – apart from Protein Power – that changed your life?

The Artist’s Way by Julia Cameron. Initially, it was hard to read in some ways. I am an atheist and it has a very spiritual message. But that book gave me the ability to see everything I do as a creative endeavour. It was life-changing.

What are you reading now?

A textbook on epistemology. I’m taking a course at Colorado University, Boulder.  I’m interested in how it is that we decide we know something and form our beliefs.

Tell me a secret?

In almost any other context, saying that I eat meat only is usually a surprise. It won’t be to you. And while it’s not really a secret and a few people know it, I want to study neuroscience at the graduate level.

What ‘s the best advice anyone ever gave you?

Trust your feelings. As someone who has had so much influence and explicit desire to be rational, that took a long time to sink in.

If you could edit your life, what would you change?

Nothing. I love where I am. I wouldn’t want to disturb that, even by accident.

What’s the craziest or most dangerous thing you’ve ever done?

I haven’t done anything extremely dangerous. The craziest was probably quitting my job three months ago, ditching a career that I had worked so hard to achieve. But it felt harder not to quit, even though it felt crazy at the time.

What’s your biggest fear?


And your hopes and dreams?

To become a neuroscientist.