I was asked this question at a cookout last weekend, and I think I answered it with a few good points, but would like to hear how everyone else would respond? In 2 million years + of evolution, we were still living in caves. In a blip on the evolutionary timeline, since the advent of agriculture, how have we have gone from living in caves, to the world we live in today, if grains and dairy are so harmful?
Well grains and agriculture may have been harmful to the individual human when it comes to long term health and longevity, but the truth is it was vital to the explosion we experienced as species. It allowed us to live in concentrated areas because we no longer had to travel around to find food, and then we could support a larger population in a smaller area for the same reason. This led to team work, tens to hundreds to thousands of people collaborating together with the same means to an end in mind. Great civilizations began to emerge and we never looked back.
Considering the fact the previous to this cavemen had to constantly find food, kill it, butcher it, stay warm, avoid predators and so on, this was obviously a huge jump. When you're constantly stressed to provide for your family and the pack, it can add up. And any one thing can kill you whether it be the flu or a grizzly bear. I'm sure our ancestors were elated to discover agriculture, must of been like winning the lottery. I'll bet they WEREN'T thinking, "hmmmm, maybe these aren't so healthy for us" :P.
So to answer your question it was an advance in human civilization, it was the start of human civilization. It hasn't truly been until the last couple hundred years that some humans have started to think, "hmmmm, maybe these aren't so healthy for us," and that is only because we have such cushy long lived lives that we now have time to care.
So agriculture was a positive adaption if you consider modern life a good thing. But that is the thing about adapting, you can always do it again and improve on something. And I think now is the time for humans to reassess things and take another step in the right direction. A step backwards maybe ;).
Agriculture supports many more people per unit of land. Population exploded due to living in one place (no need to limit babies if you don't have to carry them everywhere).
At the genome/population level, agricuture is a great success. The best thing since sliced bread. (Oh, wait, it IS sliced bread.)
But at the level of the individual, maybe not so good. But who cares if you get diabetes as long as you are capable of reproducing? (Just expanding on Rose's comment)
Because, historically, "neolithic" diets were not as grain-based as they have been in the last sixty years.
This is something that is hardly ever pointed out about grain consumption: historically, people really did not eat a lot of grains unless they were very poor (and this really only applies to certain geographical areas, as the poor in London during the 19th century lived on oysters and eels as they were stupidly cheap). Yes, people ate bread, but, historically, bread was a far different product to what we buy today: less sweet, very heavy and dense, weighed a ton, very difficult to eat much of it, required water to get down.
What you find if you look at sources that reveal dietary information for the 19th century back to the 12th in Western Europe is that those in classes above the peasant class eat a lot of meat, fish, offal and eggs (way more than people today), and grain products are not very highly used (bread and pastry, and that is about it -- indeed, pastry is more of a structural tool than anything else). And where there are prohibitions on flesh foods, such as on fast days in monasteries, they get round this by eating animal foetuses (I kid you not).
However, we live in an environment today where there is wheat or some grain derivative in almost everything. This situation has never really existed before, ever -- it is like some uber-neolithic grain madness that has been sprung upon us.
So really, prior to the lipid hypothesis gaining traction, many people ate what we might call "semi-paleo" diets anyway. Here in Britain, a cooked breakfast and "meat and two veg" for dinner was a common working class daily diet prior to about 1970. My own great grandfather's special weekly "treat" wasn't a cake or anything like that, he used to get an ounce of tripe and eat it with vinegar.
So, in short, the reason why we have gone from living in caves to the world we live in today, considering that grains and dairy are so harmful, is pretty simple. Our ancestors didn't really eat a lot of grains, not compared to people in the West today.
It wasn't agriculture as such that allowed humanity to thrive, but rather the ever-expanding division of labor that came with a more settled, propertied, individualistic human society.
Expanded division of labor > greater specialization > technological development > increased gains from trade > long-distance trade > emerging markets and money > arithmetic, complex written language, common law > civilization.
As hunter-gatherers, we could mostly only benefit from direct interaction with people we personally knew:
With the onset of civilization (money, markets, common law, long-distance trade, etc.) we were able to capture ever-increasing benefits from indirect interaction with many more people than we could ever personally know:
...I made an anthropology/economics primer thing on this here.
The problems of grain and dairy become apparent around 40, and although health can be on a downward trajectory, there is still the high probability of another 20 - 25 years of productive life.
In 65 years or more of productive life, there is plenty of time to successfully raise children and invent new things that improve the quality and quantity of life. Invention builds on invention and increases the rate of invention (larger pool to gather ideas from).
If you are speaking strictly health, clean drinking water, a functional sewer system, and washing hands has more to do with the health of a city than practically anything else.
The most drastic damage to health seems to come with modern industrial diets. If this movement were only focused on traditional Weston A. Price style eating patterns, lots of us would still be far healthier than we were with our previous ways of eating. In fact, I think that most traditional diets can probably be almost as healthy as pure paleo, if you haven't already damaged your metabolism.
For those many of us with decades-long histories of damaging our bodies by eating modern diets, it seems likely to me that the best compensation is to cut out all of the foods that are tolerated in traditional agricultural societies within the context of an otherwise healthy lifestyle. Once you are messed up, a healthier diet will only take you so far--you'll need to really cut out the toxins. Once you've fixed those problems, you may be able to re-introduce some traditional agricultural foods.
Well the Mesopotamian culture and fall is a great example. They discovered irrigation...which was vital to agricultural crops. After time, the soil became toxic due to the salts that were left from evaporation. The plants could not grow. (They did not have Monsanto's Roundup.)The over-populated areas became under-fed and war easily ravaged them.
In present day, genetically engineering foods to increase their salt tolerance is one approach used to combat salinization of the lands.
Like us, the Mesopotamians "thrived" with the advent of agriculture. Our demise is maybe more complicated and will surely be drawn out longer--but as a result what will our food look like in 100-200 years? Will EVERYTHING come in a shiny package and filled with soy and corn products? Will I-phones, medical advances and cleaner fuel sources matter when we're dying of diabetes, heart disease and auto-immune diseases of all kinds?
I guess we'll find out.
Two more possible points to consider:
extremely lean woman often stop menstruating, which really cuts back on population growth. Adding something to the diet which allows woman to gain a little weight probably resulted in a more fertility. More viable offspring likely too as the the quantity of breast milk was more abundant as well.
Grains probably keep us from being as healthy as we could be, but it the adulteration of grain products that make our society fat and sick. Corn is the primary grain culprit. Corn syrup with kill you faster than wheat ever would. The body is weakened by processed sugars like superman and kryptonite.
Eating candy bad chewing bones good.