Not all humans were on meat and fat only diet during the last ice age. There is archeological evidence which shows that humans in some parts of the world were consuming wild grains, seeds, nuts, starchy roots and tubers during the last ice age. Not all countries and lands were covered with ice sheet and glaciers...Large parts of the world such as Africa, Middle East and parts of Asia were not covered with ice sheets and humans who lived there at that time ate a variety of plant foods.

All statements of opinion, FWIW.

The one diet -- which has a few variations -- that studies consistently reveal the best health outcomes is the Mediterranean diet. Whether it's omnivore, pescatarian, vegetarian, low-carb, or high-carb, all of these versions of Mediterranean share a few features:

• high intake of plant foods
• high fiber
• lower energy density foods
• olive oil as primary fat source
• low saturated fat intake
• minimal added sugars or refined starches
• low to moderate animal protein intake (including dairy)

Science as in observational studies that observe the effect of fiber in modern diets where food has been stripped off fiber to begin with.

What is low or high fiber depends on the diet as a whole and is not a certain number to target. If you eat a steak with the right amount of fat and protein (basically eat to satiety), you won't have excess protein or bile acids reach the colon, and the meal doesn't contain any starches or sugars in the first place, so there is really no important role for fiber to play.

Fiber typically exists in food items that also have carbs (again, what a coincidence...)

I'm not claiming that humans were on meat and fat only diets, but that that was the biggest part of their diet. I honestly don't think that this is even contested by anybody anymore. Humans were apex predators and facultative carnivore for two million years, during which period our physiology was largely formed.

Humans were predators of large prey. In carnivores, predation on large prey is exclusively associated with hypercarnivory, i.e., consuming over 70% of the diet from animals. Source: https://onlinelibrary.wiley.com/doi/10.1002/ajpa.24247

When you compare for example 1 kg of cabbage to 100 grams of steak, it may seem that the cabbage plays a very big role in your meal, but they both account for roughly 250 kcals (it is just a silly energy-to-energy comparison, I'm not even considering the essential proteins and fats...). Now, eat 1 kg of cabbage and see how it feels like, and then do the same for 100 grams of steak.

Not gonna lie about it: if my body is craving grease and salt, nothing quenches that craving like a McDonald's fish sammich.

That said, (and non-smoker that I am) the healthiest thing I've ever done is shun excess sugar and processed foods.

Weight is down (30 lbs) and mental clarity is up. "Sinus congestion" issue have ceased. And I can make it through the day without a nap..

This is story telling, plain and simple.

"If I eat this thing I like to eat, believing it has the right consistency, and I eat just the just the right amount, it will be healthy".

Fact: Dietary fiber protects the colon from the harmful effects of red meat.

Not only is it contested, it's considered bunk by anthropological nutrition scientists. The consensus is that ancestral diets were predominantly plant-based. Your claim is considered false.

To the best of my knowledge there is no known mechanism by which red meat causes colon, colorectal, or rectal cancel, but if you know of a study please report it here.

Even if we take epidemiological studies at face value, the most recent meta-analyses, like this one, suggest a hazard ratio of 1.2 on average across these cancers, which would roughly translate (for the case of these cancers) to 1.2 high red meat eaters in 100 getting this type of cancer instead of 1 mostly vegetarian in 100, this is a 0.2 percentage points difference.

Objectively, factoring in what the average high red meat and the average vegetarian/vegan diets look like, the former one being largely driven by fast food and the second one being the result of a more health conscious approach, this is "evidence" pointing to the opposite direction, namely, the direction that red meat might be actually the (indirectly) protective component in a junk diet; because obesity and type 2 diabetes have hazard ratios of 1.3 on average, each standalone, and the best path to reach these conditions would be to replace whatever meat exists in junk food with more carbs. So, if you are having junk food, at least make sure that it is "based" around meat, and not sugar.

The earliest sign of **** appeared around the time when the ice age started, 2.5 million years ago, before that, we, as in great apes, where largely herbivores. Eating nutrient-dense food in the form of animals during the ice age, their meat, their fat, their organs, their marrow, allowed for our brains, an energy hog when compared proportionally to the rest of our bodies, to develop.

Like, really, what is good (necessary even) for our brain and cognitive function? Iron, ω3s, B vitamins, especially B12, Vitamin D, Choline. Where are all these found in abundance? Eggs, fish, and meat (dairy helps too).

edit:// Lol, the asterisks appeared because I wrote "omo" and the letter "h" just before that.

I am not sure an ancient diet is something to emulate as it might lead to ancient health outcomes. Were cavehumans able to advance society? Were they even able to live long?

The Mediterranean diet sounds good, and it resembles my own. But it is determined to be good for all humans, including, say those who live in the Arctic?

It'd probably be for the worse to emulate it, not with respect to health I think, but with respect to quality/fun of life, as it is too restrictive an approach, and not necessary. Many (most?) of the animals that existed then do not exist now anyway, though we can find animals with similar compositions I guess.

I'm from Greece and I wouldn't be able to give you an exact definition of the traditional Mediterranean diet (scratch today's diet, because we are 1st or 2nd in child obesity in Europe, I think the ranking depends on the age-range.) But, for example, our culture used to have a very big religious aspect, the Greek Orthodox Church and all that, and there is the period of the Great Lent, where we are supposed to fast for 40 days to emulate the 40 days of Jesus's fasting in the desert and enduring temptation by Satan. So, you are supposed to physically suffer to a certain extent, in order to connect with your spirituality, strengthen your ideals/morals, come closer to God, etc. What is prohibited? Meat, fish, dairy products, eggs, wine, and (olive) oil. Nobody cares about beans, what are you gonna do? Eat a kilo of them without even oil? Good luck passing them through your intestines.

So, even if I didn't know how my (great) grand-parents lived, the above would already be a strong indication that meat, fish, dairy products, eggs, wine, and (olive) oil form the backbone of the Greek diet. But I do know how they lived, and in general, yes, on one hand there were plenty of vegetables and wild herbs, basically anything that you can imagine growing in a small garden or find in nature (chorta are pretty good), but on the other hand the biggest part of nutrition was coming from eggs, dairy, mostly in the form of Greek yogurt, tzatziki dip, Feta cheese, and other hard cheeses like graviera and kasseri, small and big fish (sardines, obviously) and fish roe, shellfish, especially octupus, squid (calamari), and shrimp, lamb, goat, poultry, porc, wild boar, rabbit, other game meat like some small birds (blackbirds), and to a lesser extent beef (compared to lamb and goat especially). So animal proteins were the base, and plants were used to create as much volume as possible. You have to consider that the population of the past was very poor, so also very resourceful. Now some had more game meat (in the mountains), and others more fish (near the sea), but it was some distribution of those items.

You were going to plow the fields all day? Scrambled eggs with feta cheese and a ton of olive oil in the pan (tsaklatista), a literal fat + protein bomb, with some bread and a tomato and olives and you were good to go. Greek salad, good stuff, always comes with feta cheese, you'd probably go to jail if you offered one without it. Small snacks, mezedes (tapas), are typically meat balls, small fish, some cold cut, some cheese in various shapes and forms, or stuffed vine leaves with minced meat and rice, dolmadakia. Greek yogurt, 10% fat, straggisto, with honey, nuts, and fruit if there were any could be a nice small meal too.

Now, to be clear, definitely not a meat-fest as some people will make it out to be, but also not really a plant-based diet.

Everyone's ancestry is different.

I'm Viking/northern European/Ireland via the Vikings - almost 100%. I have zero genetics from any southern based populations - zero.

Our family ancestry lived off fats, proteins, dairy, whole grains and root veggies - with a min amount of fruit and sugars. In that order.

My entire family is T2 diabetic - presumably from the old food pyramid and the SAD (standard American diet).

-With a grain/carb centric diet - I have all sorts of very negative health issues. Out of control T2, high cholesterol, inflammation, high blood pressure - complete metabolic disease.
-With a more Viking based diet - I have none of the above.

No food pyramid is a cover all for all people. No one diet plan is a cover all for all people. Not one of us can speak in absolutes about anything.

That being said - I personally think the new food pyramid is better overall than the old food pyramid. Carbs are not an essential nutrient - human bodies actually need very little. Diets based on heavy pasta, grains, cereals, fruits... =excess of many things we just flat don't need.

Couple that excess with the fact that most of the "grains" we have here in the US are so heavily modified and stripped of anything good - it all complies to where our population is right now. Which for the most part is fat and unhealthy.


Plant people - I have no problem with anyone wanting to be plant based, eat diets heavy in plants. But y'all here in the US need to consider something, and this is major -- our crops are sprayed with some NASTY STUFF. VERY NASTY STUFF. Stuff banned by most other places in the world.

Reduce cancer by eating fiber!! Fiber that is sprayed with some of the nastiest cancer causing agents known...

I appreciate all of the breadth of input here.

A cousin of mine says his health improved a year or two ago, and he lost his excess weight. I think he's younger than 40. He attributes it to what he calls a carnivore diet. I don't know the details of his diet but I think he eats some plant food but not much. I suspect his health and weigh improved because he (probably) switched from crappy food to fresh whole foods. Eating mostly meat sounds crazy but it's working for him. Maybe it won't work out for him long-term, and maybe he'll realize he needs the fiber and vitamins and minerals in plant foods, but so far, it's an improvement for him. I'm not recommending whatever it is he's doing, just giving another perspective.

Allow me to also share a pic from a visit to some very elderly uncles a few years back, which I think is a very representative depiction of a traditional Greek home-cooked meal: Goat meat with potatoes in the oven, cooked in olive oil, some real bread that will turn to stone the next day, and a small tomato salad with some feta and graviera cheese as a side. (Salads are basically a hack to consume more olive oil.)

Mechanisms of red meat consumption's causal link to colorectal cancer:

1. Heme iron in red meat -> oxidative stress -> chronic cellular injury -> cell turnover -> malignancy
2. High animal fat intake -> bile acids -> cellular injury -> malignancy
3. Altered microbiome -> pro-inflammatory bacteria -> cellular injury -> malignancy

Cross et al 2010 is a well-respected large cohort study of the colorectal cancer risks from red and processed meats, with a break-out of the potential mechanisms.

7-year hazard ratios:

• red meat 1.24
• processed meat 1.16
• heme iron 1.12
• nitrate from processed meats 1.16
• heterocyclic amine intake 1.19, 1.17

NOTE: "Cohort study, eh? What about this confounding variable I just thought about?" Study was adjusted for: gender, education, BMI, smoking, intake of total energy, fiber and calcium consumption.

Most likely, your cousin found a diet gimmick that has him eating fewer calories, which has produced the body fat loss. All weight loss diets are gimmicks to get you to reduce your calorie intake. And reducing body fat will make just about anyone feel better.

It was a rhetorical question... If a causal mechanism had been identified for red meat, then it would have been for sure classified as a class 1 carcinogen. Also note that it can make it to class 1 without ever establishing a causal mechanism, but just by evidence that are considered very strong.

It is impossible to have complete knowledge of all confounders, and the adjustments themselves carry errors anyway.

This reads more like a ChatGPT-based sequence of logical leaps.

You described it yourself! It is a diet that is solely based on animal protein and fat. From a physiological standpoint, this is one of the simplest nutritionally complete diets that a human could be on, with an asterisk on Vitamin C. I think it can be a good way to reset your body if you need to, you start from a baseline, and then add in more food items and observe what works or not.

Absolutely false. There are quite a few essential nutrients besides vitamin C that are left out.

And even getting all the essential nutrients isn't necessarily a indication a diet is healthy if it also has a lot of other things included with it that are detriments to health.

"Epidemiology is guesswork, and multivariate regression is witchcraft! The experts are wrong!"

Sure they are.

So, what essential nutrients would be left out on a diet of eggs, fish, and meat?

I think there would be a great deal of vitamins and minerals if you didn't have a variety of plant food. And you need fiber, too. Also there have been studies on how a high fat, high protein diet can cause inflammation, premature disease, etc. I've read about serious problems with a great many kinds of diets. There certainly is an element of guesswork, so you have to guess what's right for you after learning what you can.

understatement of the century

A diet consisting solely of eggs, fish, and meat (with the organs) would actually cover all essential nutrients!

However, this is (almost) a minimal set of food groups for getting all essential nutrients, one can always add more things, and personally I think that one should. Unless you are suffering from some food allergy or related condition and need to drop to a baseline in order to reconstruct your diet, there is no reason for restricting your diet that much (or unless you want to of course).

That said I've never met a long-term carnivore in person, I have a colleague who used to be a boxer in his national team when he was young and he only did steak and protein powder for 6 months, he had no issues and felt great, but it became boring. I have also spent a good week or so clearing the fridge of goat cheese, eggs, and butter when I had an accident and couldn't move around easily to do the groceries, and I healed up super fast.

Fiber is very important and it was a huge part of ancient diets, that's why cancer and heart disease was almost non-existent in the old days. Fiber removes toxins and bad cholesterol from the body, helps with digestion and feeds gut bacteria. I know that fermented dairy is great for gut bacteria too, but that doesn't mean you should skimp on fiber. Majority of people in the western world are not deficient on protein but they are seriously deficient in fiber.

I hear a lot of people on the carnivore diet are starting to include more carbs into their diet. As for eating organs, I agree, you get more out of it than simply the meat of the animal, but organs are not part of the new federal nutritional guidelines. And I can start smoking, do it for six months and not feel much issues.

Also, WRT to eating meat, I think there are a lot of issues in the same way there are issues with eating plant foods, i.e. due to the unhealthy/unnatural conditions. That's why I'm a big proponent in Regenerative Ranching/Farming. Not at all the same as the USDA run program of Organic Foods, nor is it the same as many types of "Grass Fed" beef.

Simple fact is, we are omnivores. I think all these diets of Carnivore, Fruitarian, etc.,,, Vegan is more about ideology, than rational thought.



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I really don't understand this craze about the fiber, because in a real, whole food diet it shouldn't be of any concern whether the fiber is low or high, there is simply no low or high (well, I guess there can be a high, but you have to make really poor food choices, like eating just the skins of vegetables).

How does fiber support or "feed" the colon? We eat the food with the fiber, then the fiber reaches the colon and the gut bacteria eat it, and finally the gut bacteria poop short-chain fatty acids, of which the most important one in our story is butyrate, because it makes the vast majority of the nutrition requirement of colon cells.

What happens if you don't eat fiber? As we are in a real, whole food diet, this basically means that we aren't getting any carbs in either, so we will be going through some ketogenic phases and we will have some ketones flowing around our body, such as β-hydroxybutyrate (note the butyrate part there), which will feed the colon cells.

Like, damn, it seems that our body has so many redundancy systems. But we managed to outsmart it by stripping the foods off fiber and presenting it with something that it would never see in constant abundance in nature: refined carbs. And now we say, oh yeah it is very important to have 30 grams of fiber per day. How did that number even come to be? If one day I want to do 10 apples, then the fiber intake should be 50 grams, because that is how much fiber is in 10 apples. If another day I want to do 1 kg of sardines with their nice shiny skin and their mildly crunchy bones, then the fiber intake could be 0 grams with no issues whatsoever, because I'm not getting in any carbs and my liver will make β-hydroxybutyrate!

I do not understand the concern with what ancient people ate. They did not live as long. Sanitation was poor. Infectious disease was rampant. Work was hazardous. Lions would eat you; dinosaurs too! Ok, I added that last one for a laugh. Mothers died in childbirth. Many children died very young. Nutritional deficiencies where commonplace.

Why the yearning for the "good old days?" BTW, what "good old days" are we talking about? The 1600's? The 1000's? 5000 BCE?