There were a few points mentioned by @Sunshine@lemmy.ca about the negative aspect of carnivore diets on health: https://lemmy.world/comment/14453309
Here are some sources on why the carnivore diet is completely unhealthy:
While there is debate in the scientific community over just how much meat belongs in a human diet, it is impossible for all or even most humans to eat primarily meat. Beef production at the scale required to feed billions of humans even at current levels of consumption is environmentally unsustainable. It is not even healthy from a theoretical evolutionary viewpoint, the microbiome expert Gilbert explained to me. Carnivores need to eat meat or else they die; humans do not. “The carnivore gastrointestinal tract is completely different from the human gastrointestinal tract, which is made up of a system designed to consume large quantities of complex fibers.”
Christopher Gardner, a professor of medicine at Stanford University, is less convinced by the evidence.
“Are these T rex? African lions? Or humans? Assuming [you are referring to] humans, this sounds disastrous on multiple levels,” he said.
The lack of dietary fibre in an all-meat diet is likely to wreak havoc on the bacteria in our colons, known as the microbiome, he said. “Growing evidence suggests that in the absence of adequate fibre, the bacteria in the colon consume and thin the protective mucus lining, which then leads to impaired immune function and inflammation.”
Eating more meat also contributes to a rise in a substance called trimethylamine N-oxide in the blood which, according to research by the Cleveland Heart Lab, may be as bad for heart disease as saturated fat and elevated cholesterol.
Factory farming of animals is also linked to antibiotic resistance in humans and is a huge contributor to the greenhouse gases that contribute to global warming.
“In summary, I think a ‘carnivore diet’ is inappropriate for human health, bad for the health of our planet, abusive of the human labour force that handles the preparation of meat, abusive of animal rights and welfare,” he said.
By skipping fruits and vegetables, people likely won’t get enough fiber in their diets, which can affect gut health. They also will miss out on carotenoids and polyphenols, substances with antioxidant properties that have been linked to lower risk of chronic diseases such as Type 2 diabetes and some types of cancer. Animal products also contain high amounts of saturated fat and cholesterol.
In addition to the potentially adverse health effects of the diet, Willett, professor of epidemiology and nutrition, noted that industrial production of animal-based foods is harmful to the planet. “There’s also the issue of justice that basically the Global North—Europe [and] the United States—cause most of the problems with climate change that we have today, and this sort of perpetuates that.”
Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids Pg 275
Carbohydrates (that includes Fibre) are not essential for human life.
I’m not trying to recruit people, this is an area of interest of mine, and I want to talk about it with other people who are interested in the area. Eat whatever diet you want, if your getting good outcomes (Including being insulin sensitive) - great, more power too you.
Per my post https://hackertalks.com/post/5770624 must nutritional science is very poor quality, on the bottom of the evidence pyramid. Even the meta-analysis is meta-analysis of observational studies, which is only as good as the observational studies they are built on. The few RCTs I can find are not to hard end points, but rather focus on biomarkers that are assumed to be bad endpoints (such as elevated LDL - which has been shown in actual RCTs with all cause mortality to not be a danger).
Since I imagine the tire fire from this post will be epic, I’m going to respond to each point individually in its own comment. I wont talk across points on different threads - keep the conversation on each issue topical.
Full disclosure I moderate the following relevant communities (but not this one)
Nor I, but I can’t help but tell those I care about how much dumping veg helped me
Type 2 Diabetes
This is said without any context of a low carbohydrate or carnivore diet. This is a example, generously, of throwing things at the wall to see what will stick.
Type 2 diabetes can be defined as the state of carbohydrate intolerance. People cannot control their blood glucose, because they’re not producing sufficient levels of insulin to overcome their incumbent insulin resistance.
If somebody is carbohydrate intolerant, why would a diet without any carbohydrates in it, cause carbohydrate intolerance?
I would love to see a randomized control trial comparing a low carbohydrate diet, even a carnivore diet, to any plant-based diet, in the context of T2DM. I don’t believe any exist, but the statement above very much assumes the context of a unhealthy Western diet. Not a low carbohydrate carnivore diet.
All the diet comparisons I have seen have compared only to standard American.
Just about anything beats standard American over the course of the few months it takes for vitamin deficiencies to kick in
Newspaper / Opinion 2
This does not speak to health outcomes or human safety, no response.
Good approach
Newspaper / Opinion 1
Expert opinion is the least credible form of evidence, and does not speak to poor health outcomes, not science, no response.
Thanks!
Fibre / Fiber :
Is fiber a necessary macro-nutrient?
Dietary Guidelines for Americans (Latest Edition)
Fiber is NOT ESSENTIAL FOR HUMAN LIFE.
U.S. Department of Health and Human Services and U.S. Department of Agriculture. 2015 – 2020 Dietary Guidelines for Americans. 8th Edition. December 2015. (Latest Edition)
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Fiber IS NOT NECESSARY, as demonstrated in this post (publish expert opinion, weak science), and the 1930’s 1 year strict carnivore hospital study post (published case series, stronger science).
For a standard nutritional analysis of carnivore post (mechanistic analysis, weak) -
Given the totality of the above it is not credible to say fiber is a essential macronutrient. Is it optimal for human health? That is a interesting, and open research question.
From personal experience I know people with Crohn’s disease, and IBS are are strict carnivores who are still alive after many years, so fiber isn’t a necessity (anecdotal data, case studies if your feeling generous, weak evidence)
Constipation RCT
Stopping or reducing dietary fiber intake reduces constipation and its associated symptoms
slide
This was a 6 month study focused on constipation, not human health in general, but none of the 41 people died, and they pooped better too
General discussion of fibre beyond “Necessity” and “Safety”
As an aside, I think its reasonable to say Fiber (since it diminishes/reduces absorption of nutrients, reduces transit time) may be a net benefit on a standard Western diet (unhealthy by default). Fiber is a good way to even out blood sugar spikes, but if your eating carnivore your not eating carbohydrates and not having blood sugar spikes anyway.
Fibre also absorbs moisture (its just wood), Fibre is not a lubricant, its a dry bulking agent.
Lots of the fiber “benefits” are claimed to be due to short-chain-fatty-acid production in the intestine… which then produce… ketones… which a carnivore diet already produces (and are available to the colonocytes in greater abundance this way and get to EVERY colonocyte, not just the ones in contact with the fiber)
SCFAs Plant vs Animal
Diet rapidly and reproducibly alters the human gut microbiome
Here is a comparison of SCFAs on different diets…
Human gut vs Herbivore gut
Humans have a vastly reduced (cecum)[https://en.wikipedia.org/wiki/Cecum#Other_animals] compared to Herbivores
These two lectures were on my “to review” list, but since my hand was forced here they are, if you are interested in the science of fiber