wheat
You are overweight. I'm sorry to be blunt, but it's probably true: most adults living in Western countries are overweight. A large portion is obese.

Half of you are taking at least one prescription medication. Half of seniors are taking at least three. You may not be on anything, but you know someone who is.

Does that sound normal? I mean, are perpetual chronic illness and obesity the normal state of existence for us? Is our wiring so inherently faulty that we can't keep ourselves alive without pills and doctors?

No. Absolutely not. It wasn't always like this, you know.

The first big turn happened with the Agricultural Revolution. Right around 10,000 years ago, when former hunter-gatherers began growing grain seeds in neat, organized rows, something happened. Population exploded, because we now had a steady source of calories. Villages and cities sprang up, because we no longer had to follow our food. We could simply grow it where we lived.

Those sound like pretty good things, at first. More food and shelter sounds good, right?

Well, something else happened, too. Those early farmers were shorter than the hunter-gatherers they replaced. They didn't live as long, and they had smaller brains. They got a lot more infectious diseases and more cavities. In short, they were not as healthy as the hunter-gatherers. Same genes, same homo sapiens, different environment, worse health.
But wait - whole grains are supposed to be healthy. Every government institution recommends making whole grains a big part of our diet. How could grain agriculture have caused all those health problems in our ancestors?
The thing about grains is that they don't care about you. Think about it: a grain of wheat is a baby plant. A wheat egg, if you will. In order for that wheat to pass on its genes, its grain must make it into the ground, sprout, and grow up to repeat the process. Just as a hen keeps its egg warm and well-protected until it hatches, the grain needs ways to stay protected through this process and to keep other animals from eating it.

Unfortunately for the grain, it has no legs, teeth, wings, or claws. It can't fight. It can't run from predators. It looks downright defenseless, just sitting there on a puny stalk of wheat.
The grain is anything but defenseless, though. It has an array of chemical defenses, including various lectins, gluten, and phytic acid, that disrupt your digestion, cause inflammation, and prevent you from absorbing vital nutrients and minerals.
All grains contain some or all of these anti-nutrients, to varying degrees, so when our ancestors began making regular meals of them, their health suffered accordingly.

Okay - so we've got the fossil records to prove that grain agriculture brought illness and poorer health to human populations, but we don't know if those early farmers were obese. They probably weren't. Even if you look at photos of Americans from the 1930s through the 60s, just about everyone is thin. How's that?

Let's keep going.

That brings me to the second shift: the late 1970s. Up until then, the obesity rate in America had stayed fairly constant at around 12% of the adult population. Not great, but not too bad for an affluent society with easy access to food.

Starting in the early 80s, things changed. Obesity rates began a steady, constant climb until today, where almost 30% of the adult population is obese and 70% is overweight and/or obese. 1 in 3 American adults is obese. More than 2 in 3 are overweight. Does this seem right?

What the heck changed?
The low-fat diet craze kicked off. People were told that fat and cholesterol were killing them (based on terrible science, which I'll get into in a future lesson) and making them fat.
So, to avoid all that fat, they started eating more grains, carbs, and other processed low-fat foods.

The other thing about grains (and carbs in general) is that they raise your body's insulin levels. Insulin is required to shuttle nutrients, like carbs and protein, into various cells of the body. You eat carbs and insulin deals with them. But if you eat too many carbs - like, say, a person who was just told never to eat fat and to eat all the low-fat, high-sugar processed grain products they wanted might do - without exercising at an insane level, your body pumps too much insulin and you get insulin resistant.

When you're insulin resistant, any amount of carbohydrate will not be tolerated. It will turn to body fat, and the more body fat you have, the more insulin resistant you get. The more insulin resistant you are, the less nutrients are being shuttled into your cells, meaning you stay hungry even though you're eating, so you eat even more carbs that you can't tolerate. It's a vicious cycle, you see, and it's led to the mess we're in.

To make things even worse, many of the carbs we're now eating come in the form of sugar, or its cheaper, more widespread alternative, high-fructose corn syrup. Both forms of sugar are high in fructose, which the liver turns into liver glycogen, a type of carb-based energy, until its glycogen stores are full. Those glycogen stores fill up fast, and since most people aren't using any glycogen (kinda hard to do that when you have to work an office job and sit in traffic all day), that fructose turns to liver fat.
Together, a diet high in sugar and refined grains, and low in fat, has begotten the obese, diseased populace we see today. That's the bad news. The good news is that solving the problem - at least on an individual level - is easy.
All you have to do is follow Primal Blueprint Law #9: "Avoid poisonous things." Those food toxins that grains use to defend themselves? Those are poisonous things that you should stop eating.

So ditch the grains. Here's how. Give up the bread. Reduce your overall carb intake. (See the Primal Blueprint Carbohydrate Curve.) Even if you aren't overweight, I guarantee you'll feel better without that poison in your life.