To bad it's environmentally unsustainable. There's no way our ecosystem can survive all of us eating eggs, tuna, and chicken all day. We need to consume less animal products not more. Low carb is fine for a few wealthy people who want to lose weight but it's not a responsible solution to the public health problem.
What about a low-junk food diet? No cqlorie restrictions but no refined carbs? I don't think we need ti discourage people from eating whole grains and beans.
Eggs are probably "mostly fine" to be honest. Most homes could easily raise their own chickens and have a nearly unlimited supply.
As a prepper and a homesteader (amateur/beginner), I realize that low carb and high fat/meat isn't really feasible when SHTF, and I mostly stock lentils, pintos, rice, wheat, quinoa, and a few other standard staples. They stay good, when properly sealed for like 25 years (quinoa only 8 years or so though...). No meat known to man (or at least myself) does that. Also, even doing basic homesteading, you tend to eat more veggies and much less meat.
In the meantime, I admit that I eat plenty of meat, and could probably raise a cow or some pigs, or at the very least do the rabbit thing, but it's a lot of work and planning, and it's just easier to get your meat from a can in an emergency situation.
Edit: I prep for emergencies, FWIW, not health. Calories and nutrition are the major requirements.
Low carb doesn't necessarily mean more animal products. It can mean that you replace the carbs with nuts and veggies, so that you are getting more of your calories from protein and healthy fats.
100 calories of nuts or broccoli costs a whole lot more than 100 calories of bread or rice, and this is reflective of the greater agricultural demands of pretty much everything else versus bread and rice.
Even rice is a substantial improvement in glycemic index over refined wheat and sugars. If it does turn out that empty carbs are a major public health problem, there are incremental improvements that can be made all over the world regardless of poverty.
Nuts are hardly our saviors. Most nuts are expensive & environmentally unfriendly. Which is not to say you shouldn't eat some nuts, but they can hardly step in as a global staple.
Your definition of environmental sustainability implicitly assumes a fixed, or arbitrarily bounded, population size in steady state. Whatever set of foods we choose to feed the population with, it is always possible (and historically has been inevitable) for the population to outgrow the available supply.
Sustainability only makes sense relative to a particular population size, and so something is only unsustainable in the absolute sense if the population needed to produce it exceeds the population which can survive upon it. This is not the case with the food types you refer to, and the producer/consumer ratio is precisely the thing that we develop new technologies to reduce.
If anything, I see it is better for us to engage in inefficient land use, because it provides spare capacity which can be used to mitigate prolonged disasters; a view strongly influenced by the book "The Collapse of Complex Societies", by Joseph Tainter.
You can do a keto diet and still be vegetarian. Don't know about vegans. But anyway, cheese, nuts, avacados, cooking with olive oil and butter. More here: http://www.reddit.com/r/vegetarianketo
One important note is that they probably mean "low NET carb", in other words, the grams of carbs left after you subtract them from the grams of fiber (since fiber isn't absorbed).
i had no idea that acres of monoculture crops that erode the topsoil and destroy the land and don't let anything else live on them was sustainable, thanks for clarifying.
start eating animal organs - liver, kidney, tongue, brain, throat, face meat, bone marrow - see how much food is actually in an animal.
Yep, and there will never be a world where we all eat the same thing. Let the poor eat wheat.
Paleo is pretty affordable at the lower-middle class, if you're willing to put the effort in and cook. My biggest hurdle is how easy unhealthy stuff is.
What about a low-junk food diet? No cqlorie restrictions but no refined carbs? I don't think we need ti discourage people from eating whole grains and beans.