Jeb Bush, running hard in the run-up to actually running for president, has a strange sideline. He has become both guinea pig and pitchman for the paleo diet. Bush has lost about 30 pounds since December by sticking to an abstemious regimen intended to mimic that of human ancestors from the Paleolithic period, the time frame from the early use of stone tools (about 2.6 million years ago) up to the the start of civilization (about 10,000 years ago) that shaped the human body in its current form. In theory this mimics the diet of a prehistoric hunter-gatherer: lean meats, fruits, tubers. No bread, grains or pastas. No dairy. This isn’t pleasant.
“I am always hungry,” he said.
Jeb Bush is thinking of running for president.
And he is starving.
As he prepares to challenge an almost universally younger and svelter field of Republican rivals, Mr. Bush has adopted a drastic weight-loss program that is melting away pounds at a staggering rate even as it inflicts an unhappy toll: regular bouts of dietary crankiness.
What a presidential candidate does gets a lot of attention, everything he or she does has some influence on public perceptions. If Bush is a walking, talking commercial for the paleo diet, more people – probably more Republicans than Democrats, not that that matters – will buy into the premise, tell their friends about it, and try it. This may be better than a pizza-eating Bush. But not by much.
There is nothing inherently *wrong* about the paleo diet. It's not dangerous. It can, indeed, help you lose weight, as Bush has found. But its scientific pretensions, with their penumbra of evolutionary validation, don’t mean much. It’s true that our big brains, upright posture, and small guts – unique in the animal kingdom – evolved on hunter-gatherer diets. But the key lesson here is flexibility.
Modern humans emerged in Africa in a kind of evolutionary competition, with new proto-human species appearing and disappearing in constantly changing habitats and climates. And as Homo sapiens spread around the world starting about 60,000 years ago, they lived in, and thrived in, nearly every habitat on earth. No single diet was responsible for success or failure. Meat certainly played a role. So did cooking. But more than anything, it was early humans’ adaptability to varying diets that ensured success. Big brains and social natures gave early humans the ingenuity and the means to find and exploit new food sources. This is one reason why there is such variety, and such extremes, in cuisine today. Even modern hunter-gatherers diets vary considerably by geography.
It’s also not like people stopped evolving 10,000 years ago, with the advent of fixed settlement, farming, herding and dairying. Cow’s milk, for instance, is highly nutritious, and so after people managed to tame aurochs (wild cattle) about 8,000 years ago, they unlocked a fantastic new food source. Humans adapted with the spread of genes for lactose tolerance, so more people could drink up.
You could create a fad diet out of almost any ancient food template. The dairying diet. The whale-hunter’s diet. The shore-scrounger’s crab-and-berry diet. The bark-n-nuts diet. The bitter potato diet. And any or all could plausibly keep you going and, depending on caloric intake, lead to weight loss, precisely because human tastes and bodies are versatile. The real challenge is not eating good stuff, it's systematically avoiding the bad.
In that sense, the paleo diet is a modern social construct, a fantasy useful mainly for conjuring motivational images of lithe cavemen. But there is no real way to recreate an ideal diet out of the distant past, because we don’t live in the distant past; our bodies have been conditioned by thousands of years of civilization, and by the years we’ve been alive, eating. Nor do our patterns of movement, living habits, and daily challenges – even those of campaigning politicians – remotely resemble those of hunter-gatherers.
He could do worse than the paleo diet, I guess. But by making himself a poster child for it, Bush is setting himself up for a fall, either when he lapses (like many, he has lapsed before, and if you’re always hungry it usually means, well, you’re not eating enough), or when campaign scrutiny of all aspects of his life grows so intense that he is unable to defend it. Presidential aspirants should do themselves, and us, a favor and steer clear of fad diets.
