En español | Does any old apple a day keep the doctor away? Or does it have to be organic? The answer is, honestly, “That's impossible to say right now.”
Why is that? First of all, almost nobody eats purely organic versus purely nonorganic, so it's impossible to divide people into two groups for comparison. There's an overlap, and when two groups that are supposed to be different are a bit alike, their outcomes look more like one another.
So there's no evidence that organic foods are better for you? We didn't say that. There is a burgeoning array of large observational studies that look at people who reported willfully eating organic routinely versus people who didn't. As of this writing, the most recent study is out of France, where researchers found a significant difference in cancer incidence between those who eat organic routinely versus those who don't. (Those people who ate organic most often had the least cancer, as you'd expect.)
Well, doesn't that mean that organic is better after all, if it keeps you from getting cancer? The study really isn't conclusive, though.
Aaargh. Why not? Maybe what makes the two groups different is the total level of care they take with their health. It could be that all those people eating organic have access to better medical care, more cash to spend, higher quality of life — that kind of thing. Generally, organic food costs more, which means more well-to-do people — those with better health care and usually better living situations — are more likely to be the ones eating better. So we still don't know for sure. But at least, for the first time, we have a strong association between routine consumption of organic food and an important health outcome.
If I'm looking at organic and nonorganic apples side by side at a store and I can't afford the organic ones, what should I do? A nonorganic apple is better than no apple and better than most other choices. Rinsing conventionally grown produce reduces the pesticide residue and so arguably narrows the difference between organic and not organic. So, yes, get the nonorganic apples and wash them well. It's almost safe to say, “Never pass up an apple.”
What about trying to eat locally? "Locavore” is a relatively new term but an ancient way of eating. Locavores eat — or try to eat — food produced locally, although, of course, the word “local” is pretty vague. Before food was shipped, everyone was a locavore. Now the term has come to have a deeper meaning: that what you eat matters to your health, and the quality and composition of what you eat are in turn determined by how the food is raised, what it's fed and where it's from.
Why is it worth spending extra time and, usually, money to eat locally? Reducing the carbon footprint, supporting local economies, eating seasonally (and fresh), knowing where your food comes from and how it was raised … all these are inarguably positive attributes, and all are characteristics of local food. No one but a fanatic could eat only local food, but concentrating on these attributes would mean you were eating better, more ethically, more sustainably. If you know your produce is being grown on a local farm where chemicals are not being used, you know that you are avoiding those chemicals. If you know the soil is being nurtured appropriately, you know it's rich in nutrients. If your food has not been in storage and transit for days or weeks, it will have much more of its native nutrient content when you eat it.
Don't Panic, Eat Organic
Since 2004, the Environmental Working Group has been publishing the Dirty Dozen, its annual list of fruits and vegetables most likely to contain pesticide residue, even after being washed. If you're choosing to buy some organic produce, these are the ones to prioritize.
So local sourcing means the foods have better nutrient composition? In general, yes; though if you're sourcing industrially produced corn locally, then probably not. It makes sense that agriculture and health are connected — there's no way around it. So the more you know about how and where plants are grown, the more confident you can be about their nutrient quality.
Does soil composition affect animal products, too? Oh yeah. This issue is even more important when you consider animal foods. The nutrient composition of meat is substantially connected with the diet and exercise pattern of the animal. Meat is leaner and has less saturated fat when animals get more exercise, for instance. The composition of meat also varies with what animals eat and the nutrients in those plants, which are in turn influenced by the soil.
Healthy, nutritious soil means healthy, nutritious meat? When animals graze on grass, as opposed to grains, they keep the soil healthy and produce better meat. And pasture-raised animals may have lower risks of industrial foodborne scourges like E. coli O157:H7, a strain that can cause severe infection and even kidney failure. It came from the intestines of cattle, particularly those that were fed grain rather than grass! So if animal rights and environmentalist arguments don't motivate you to eat local, remember that it also matters to your personal health.
Having said that, it is, of course, possible to produce bad or nutritionally deficient food locally. But a main advantage of sourcing locally is that you can see or learn about the production of your food and easily make that judgment. It's also pretty safe to say that a locavore diet does not include nationally distributed food products made in a factory somewhere, which pretty much means it excludes junk food.
Does that mean locavores can eat whatever they want? Grass-fed burgers and locally produced cheese all day! Not exactly. It's still important to have a plant-predominant diet, along with balance and variety.
Adapted from How to Eat: All Your Food and Diet Questions Answered by Mark Bittman and David L. Katz, M.D., published this month by Houghton Mifflin Harcourt. Used by permission.