Is it a good idea to eat only meat?
Interest in the carnivore diet, a no-plants zero-carb diet, is increasing. And perhaps for good reasons – some people report a lot of benefits from it.
Here’s a good article looking into the phenomenon:
Optimising Nutrition: Dr. Shawn Baker’s carnivore diet: a review
If you don’t feel like reading the whole article, you can skip to the summary. Here are the main points:
- Some people seem to benefit from a zero carb/carnivore diet, particularly if they have pre-existing gut permeability or bacterial overgrowth.
- Cutting out nutrient-poor processed inflammatory foods is a common denominator in many successful diets.
- It is harder to get some nutrients without plants, however, some of these nutrients may not be such a big deal if you are not eating a lot of carbohydrates.
- While there are plenty of anecdotes, there is not yet a lot of large-scale quantitative research into the long-term impacts of a carnivore diet.
- It’s still a good idea to maximise the micronutrients in your diet irrespective of your overarching dietary template.
Meat
Earlier
Carnivory – Could you benefit from eating an all-meat diet?
A diet of steak, bacon and water – why techies are turning to ‘carnivory’
Personally, I've found going to mostly meat has had benefits for me, though I have not yet transitioned to all meat. I take magnesium and vitamin D (never in sun). Mg infrequently, vitamin D daily. The Mg I also took while on low carb but with lots of vegetables, nuts, dairy. So, it's unclear whether I have an issue and not the diet. I feel great and don't have any issues I know of.
As Bob pointed out, those RDAs are based on high carb diets. When you change what metabolic pathways are most prominent, you change your nutritional needs, sometimes a lot. Further down in the article, Marty links to my research into the changing need for vitamin C on a low carb diet, for example.
Not only that, but the USDA table for vitamin C in meat is wrong. If you look at their paper documenting their measurements, they didn't measure it at all, but assumed it was zero, which it's not. I've written about that here: http://www.empiri.ca/2017/02/c-is-for-carnivore.html
A second problem is that plants often interfere with absorption of nutrients. This artificially inflates the RDA. That can't be accounted for in this counting system.
Livestock conditions may also be pertinent. For example, pastured pig fat is purportedly very high in vitamin D. So sourcing might matter.
We know that no large trials have been done on low or no carb diets, and high fat, while we know that every high carb low fat trial/epidemiological study have achieved abysmal results and often at the expense of other health markers. Lowering the colesterol often meant more cancer, more mental issues and general decay of health, even if heart attack risk was lower.