Pesticide exposure: separating facts from fears

An advocacy group called Friends of the Earth has been publicizing the results of a new study demonstrating that when people switch from a regular diet to one containing only organic foods, their exposure to pesticides is reduced.

The study recruited four families from different corners of the country.  Each family ate a non-organic diet for six days and an all-organic diet for six days. The researchers found that the organic diet “rapidly and dramatically reduced exposure to pesticides.” 

That’s not terribly surprising.  In fact, it’s so unsurprising, it’s a little hard to imagine why the researchers felt the need to do this study.

The far more important question (not answered in this study) is: Is this something we need to worry about?

Relatively major but absolutely minor

In reporting their findings, the Friends of the Earth present the difference in exposure in relative terms. “Levels of all detected chemicals dropped an average of 60.5 percent with a range of 37 percent to 95 percent depending on the compound.”

But they don’t give us any information about the absolute levels of exposure.  This is at least as important as the relative exposure. Celery has 40 times as much sodium as cucumber. It’s still a low sodium food.

Did those higher levels of exposure pose any sort of threat? Or were they (as I suspect) well below the threshold of concern?

Good Riddance to Bad Rubbish

Secondly, the coverage repeatedly talks about the “pesticide levels in the bodies” of the subjects. But the study didn’t test the subjects’ blood or tissues. They tested their urine, which is where the body discards things it doesn’t want or need.  Furthermore, what they found in the urine were compounds formed when the pesticides were broken down by the liver.

In other words, what they found was evidence that the body’s detoxification systems were working exactly as they are supposed to, breaking down and excreting potentially harmful compounds. The pesticides these families were being exposed to by eating a non-organic diet were apparently being eliminated from their bodies.

So I have to ask once again: Is this really something that we need to worry about?

One of these things is not like the other

The organization points out that one of the pesticides monitored in this study is frequently linked to farmworker poisonings.  That’s a great argument for farmers using more care when working with agricultural chemicals (and that goes for synthetic as well as organic chemicals). But it doesn’t really have anything to do with risks that families might be exposed to by eating conventional produce.  And yet, by juxtaposing these two facts in the press release, it implies that eating non-organic foods increases your risk of chemical poisoning.  There is absolutely no data to support this implication.

Good news is no news?

Meanwhile, the press reports don’t mention that a third of the compounds they were testing for were undetectable in the urine samples after the non-organic diet. You have to wonder whether they were, perversely, somewhat disappointed by this.  They certainly didn’t seem very eager to publicize the fact that some of the most common pesticides used in conventional agriculture apparently pose little risk to eaters.

So, what’s the upshot of all this?

The Friends of the Earth concludes that “these results show that eating organic works.”  Works how, exactly? Yes, eating organic  reduces your exposure to certain (but not all) pesticides. But does it reduce your risk of disease or harm? I don’t see any evidence of that here.

This is Important. Let’s Get it Right

Lest you think I am pro-pesticide, or anti-organic, let me assure you I’m not. I’m just against this sort of sloppy communication and manipulative “science.”

Conventional farmers don’t use pesticides because they’re lazy, ignorant, or uncaring. They use them, as sparingly as they can get away with, in order to maximize yields and lower the cost of food.  If they can figure out a way to use less, they are eager to do so.

Organic farmers use pesticides and herbicides, too, by the way. Some of these organic pesticides are highly toxic to beneficial insects and, if mishandled, can be harmful to humans, as well.  But organic farmers are also working to increase yield and reduce the cost of their products. And pest control is part of that.

Instead of pitting organic growers (and eaters) against conventional, why not work together to make progress on all of these important fronts? Let’s use the best technology, the best practices and, yes, the best chemistry, to create a safer, more abundant, and more sustainable food supply.

To that end, let’s assess the risks and impacts of chemical use (both synthetic and organic). Let’s weigh the costs and benefits of various options. But let’s debate the issues on their scientific merits instead of resorting to sensational, misleading, and manipulative “research” and rhetoric.

This is not an us vs. them situation. We’re all us.

Thinking of cooking that romaine? Here’s why you shouldn’t.

Lettuce soup recipe on Epicurious.com

Like many of you, when the CDC issued the warning about romaine lettuce last week, I had a package of romaine hearts in my fridge. Even though I had already eaten one, with no ill effects, the CDC is very clear that the rest should be discarded–just in case.

For reasons explained by food safety expert Dr. Robert Brackett in this episode of the Nutrition Diva podcast, washing the lettuce is not enough to remove E. coli..  The only way to kill those bugs is to heat them up to at least 160 degrees Fahrenheit and hold them there for a while.

But, like you, I hate to waste food. And I remembered being intrigued last winter by some lettuce soup recipes. Wouldn’t cooking the lettuce thoroughly in a soup be a way to safely avoid throwing this (probably perfectly fine) lettuce away? And a chance to try a new recipe to boot?

When I sat down this morning to write this post, I intended to propose just that: Make soup from whatever romaine lettuce got stranded in your crisper drawer last week.  Fortunately, I decided to run that advice by an expert before publishing it. And I’m glad I did.

Dr. Brackett has once more come to our rescue, explaining why this might not be good advice:

“While it is true that ‘thorough’ cooking should kill E. coli…it depends on the physiological state the bug is in (i.e. phase of growth, individual cells versus “clumps”, etc) as well as where the cells are physically located (internalized in the lettuce, in the middle of a clump of leaves, etc). One would really need to validate the lethality of heating romaine before one could say it was ‘thorough’.

However, another reason why CDC recommends simply discarding all romaine, is that…one could be potentially be bringing E. coli into the kitchen and creating a cross-contamination situation (counters, refrigerator, utensils, etc), or even contaminating one’s hands (and perhaps inadvertently to mouth) and risk illness if they are handling the lettuce. “

If you do have some lettuce on hand, throwing it away really is the better part of wisdom. It’s also not a bad idea to give that crisper drawer a thorough cleaning. (Let’s be honest: this is probably long past due…). Finish up with a proper hand-washing and toss the dishtowel in the laundry. (Most of us don’t do that nearly often enough either.)

Let’s hope, for everyone’s sake that the source is identified quickly. Those sickened by the bug are not the only victims here. Outbreaks like this can have a devastating–and lasting–financial impact on growers and farm workers as well.

In next week’s Nutrition Diva podcast, I’ll be talking about a not-so-new technology that could potentially prevent the next outbreak.

Surprising Link Between Diet and Brain Power

Every week seems to bring another study on the benefits of the Mediterranean diet–on heart health, longevity, cancer risk, you name it. But this study caught my eye due to a surprising connection between diet and academic performance.

The study involved a couple hundred high-school aged kids from Spain. The researchers found that those who more closely followed a Mediterranean diet pattern did better in school, getting higher grades in math, language and having higher grade point averages.

That’s not all that surprising. Previous research has found a link between Mediterranean diet and cognitive function in adults. All those healthy fats and antioxidants–and a minimum of added sugars and processed foods–appear to be good for the brain.

But the Spanish researchers found another potential explanation: The kids whose diets were most aligned with the Mediterreanean diet pattern also slept longer and better–and that this appeared to mediate the effect on academic performance. Previous studies have found that older adults who follow this dietary pattern also tend to sleep better.

But why would the Mediterranean diet lead to better sleep?  Researchers have proposed a couple of possibilities.

We know that the Mediterranean diet tends to be anti-inflammatory and there appears to be a relationship between inflammation and sleep.  When people get less sleep, their inflammation markers tend to go up.  But may also be true that higher inflammation has a negative impact on sleep quality. So it could be that the anti-inflammatory effects of the Mediterranean Diet help you sleep better.

Some of the foods that are prominent in the Mediterranean diet, including olives, olive oil, grapes, and wine, are good dietary sources of melatonin, a hormone that regulates the circadian sleep-wake cycle.  Perhaps the higher melatonin content of the Mediterranean diet has a beneficial effect on sleep rhythms.

Food for….zzzzzz

 

 

Eating gluten free will cost you

More and more consumers are convinced that avoiding gluten will improve their health. And if avoiding gluten meant cutting out breads, pasta, crackers, baked goods and other traditionally wheat-based foods, there might be health and nutritional benefits.

Replacing sandwiches with salads, pasta with zoodles, pizza crust with cauliflower crusts, baked goods with fruit–all solid upgrades in terms of nutrients (not to mention calories).

But as the selection of gluten-free breads, pastas, crackers, and baked goods grows, giving up gluten may not necessarily improve your nutrition. In fact, a recent survey found that gluten-free foods tend to be significantly LESS nutritious than the foods they are designed to replace.

According to researchers who evaluated over 1000 commercially available foods, GF breads tended to be higher in both fat and sugar.  GF items were also higher in salt, and lower in both fiber and protein than their wheat-based counterparts. They also cost, on average, two and half times as much.

There is a healthier (and cheaper) way to go gluten-free. Instead of loading up your cart with highly-processed gluten-free products made with various alternative starches, seek out whole foods and minimally processed foods that are naturally gluten-free.  Fruits, vegetables, whole grains, legumes, are a better way to fill the gaps where wheat used to be.

Where does fat go when you lose it?

Pride goeth before a fail.

When I saw this headline earlier this morning, I clicked through (Mission accomplished, headline writers) and skimmed the article, which seemed to contradict the basic facts that we all learn in nutritional biochemistry. Having not yet had my coffee (yes, I’m making lame excuses), I impulsively posted it on Facebook with a “Shame on you, CNN” comment.

Fortunately, my followers are smarter than I am…and are not afraid to tell me so. So, let me try this again, appropriately humbled.

Let’s Play Biochemistry Gotcha!

Had I been one of those-who-should-know-better surveyed by the authors, I too would have fallen into the trap and said that fat is converted into energy (with water and CO2 as byproducts). But this is not quite accurate. Continue reading “Where does fat go when you lose it?” >

What’s the best diet for your genetics?

Personalized nutrition is getting a lot of attention these days. Companies will analyze your DNA and tell you what foods and supplements you should and shouldn’t eat based on your genetic profile. But a huge new study throws cold water on the idea of matching your diet to your genetics.  Participants with a “low-carb genotype” (who would hypothetically do better on a low-carb diet) were no more successful on a low-carb diet than on a low-fat diet. The same was true for those with a “low-fat genotype.”

The study also found that, overall, low-carb diets are no better or worse than low-fat diets at producing weight loss.  Those are the two headlines from this study. (Examine.com has produced an excellent detailed analysis of the study, if you want to take a deeper dive.)

But there is so much more here that warrants mentioning. Here’s what really got my attention:

None of the study participants were asked to count or limit their calories. Instead, both groups were told to limit their intake of added sugars, refined flour and junk food, and to eat lots of vegetables and whole foods. And that was enough to produce weight loss.  In other words, when you pay attention to the quality of your food choices, the calories often take care of themselves. And when you’re eating a healthy, whole foods diet, low carb is no more effective than low fat.

When you pay attention to the quality of your food choices, the calories often take care of themselves. Click To Tweet

The other thing that’s notable about this study is that the participants received intensive coaching throughout the year. They were taught how to choose foods that kept them satisfied for fewer calories.   They were encouraged to avoid distracted eating and eat more mindfully. Making sustainable changes was a bigger priority than achieving fast weight loss.  (All of this will sound very familiar to participants of  the Weigh*less program, our 12-month coaching program for sustainable weight loss.)

Making sustainable changes matters more than achieving fast weight loss. Click To Tweet

At the end of the study, the most successful participants reported having changed their relationship to food. And that’s ultimately what’s required for permanent weight loss. Not calorie or fat or carb counting.

Click here to learn more about the Weighless Program.

This super easy hack could save you major calories

Can it really be this simple?

Researchers at the University of Surrey fed two groups of study subjects an identical pasta dish. Although the amount of food was the same, it was presented to one group as a “snack” and to the other as a “meal.”  The snackers ate standing up, using plastic utensils. The meal-eaters sat down at a table set with ceramic dishes and silverware.

A little bit later, both groups were given some additional foods to sample. Those who had merely “snacked” on the pasta dish consumed far more calories than those who felt that they’d just eaten a meal.

Doesn’t that ring true?

When we call something a snack, we tend to discount it.  It doesn’t register in quite the same way in our mental tally of how much we’ve eaten. We may not even feel as full afterward.  (Which just goes to show how much of our sensation of ‘hunger’ is actually in our heads!)

Try this: Instead of just grabbing a snack, consciously make it a meal. Even if it’s just a few bites or you don’t have much time, be sure to signal to your brain and senses that you’re satisfying your need for food.  Sit down. Put it on a plate. Mentally re-label those snacks as mini-meals and see if they don’t feel a little more satisfying.

Need to lower blood pressure? Here’s a tastier option

Over a million Americans developed high blood pressure overnight–and, no, it wasn’t the latest headlines.

The American Heart Association just lowered the bar on what is considered to a healthy blood pressure reading. Instead of anything under 140/90, you now need to shimmy under 130/80 to get the all clear.  That means that a whole bunch of people who had normal blood pressure yesterday are hypertensive today.

Diet and lifestyle change is the standard prescription in this situation. The time-tested DASH diet, in particular, has a great track record for lowering blood pressure.  But if the thought of giving up red meat and cheese leaves you feeling a bit bereft, I have good news.

Recent studies have found that modified versions of the DASH diet that include red meat and full-fat dairy products are just as effective as the more austere original.  The details are outlined in this episode of the Nutrition Diva podcast: The DASH Diet Gets an Upgrade.