Fact check: Is boxed macaroni and cheese actually toxic?

Mac and cheese is the ultimate comfort food. It’s so hearty, satisfying, and chock-full of dangerous chemicals.

Hold on, what??

After last week’s report on high levels of phthalates in boxed mac and cheese, people started paying more attention to the myriad of research on phthalates and testosterone reduction, birth abnormalities, and the like. You may have even started eying your own pantry suspiciously.

Or starting at square one, you may simply be wondering how phthalate is pronounced. Which, by the way, is THAL - EIGHT. This handy rhyming scheme may help: “THAL - EIGHT isn’t your PAL - MATE!”

Alright mate, let’s dig into the evidence, going beyond the simple sound bites you'll see in news coverage. You’re not going to get a simple “yes” or “no” answer here, because it doesn’t exist.

The ABSOLUTE MINIMUM you need to know, in 50 words or less: Boxed mac and cheese is high in phthalates because of plastic involved in processing, plus fat content. Phthalates are definitely a cause for concern, especially for infants and expecting females, but threshold doses aren’t known. It’s surprisingly easy to get high doses of phthalates from food, especially in the US.

Phthalates are in a lot of stuff other than mac and cheese boxes

Phthalates are everywhere. They can leach into your packaged foods, which are the main source of high molecular-weight phthalates (more on those later). They can also offgas from flooring and furniture (potentially linked to allergy and asthma). In one study of pregnant women, phthalates were present in 85-100% of urine samples and air samples from their houses. But how did we get from zero phthalates at the turn of the 20th century to having phthalates everywhere you look?

A quick history lesson: let’s travel back in time to 1872, before we lived in a world littered with plastic. Back then, plastic was too hard to mold into useful objects, and had limited applications. But somebody discovered that camphor was a good plasticizer (meaning good at making plastic softer, flexible, and easier to work with), and suddenly you could have cheaper plastic balls on your pool table instead of expensive ivory ones.

But camphor smells really strongly, limiting widespread use, and was replaced by phthalates in the 1930s. Fast forward to the 1950s, and plastic was suddenly everywhere. But it wasn’t until the 1970s that researchers started speculating about health effects of phthalates in foods. Now in 2017, the issue has finally gotten some public spotlight, due to last week’s (non-peer-reviewed) study.

Hold up. This study wasn’t peer reviewed?

Two things to keep in mind: this study did NOT look into phthalate health effects, and it was NOT actually a peer-reviewed, journal-published study. But even though we at Examine.com usually only focus on peer-reviewed research, neither of the above those really matters in this case.

Basically, a coalition of food safety and public health groups commissioned this research, in order to put the main producer of mac and cheese on blast, intending to protect children and infants who are exposed to phthalates. The research on health effects was already pretty extensive, at least in animals (it’s not ethical to feed humans chemicals and see what diseases result), so this was purely a measurement study. And since it takes many months to publish most studies, and this isn’t some ivory tower research that can wait, they wanted to get the results out pronto.

Note that measuring phthalate levels in foods is actually quite difficult. Different brands of the same food can have different phthalate levels, and measurement is prone to error because of contamination from plastic lab equipment. So not that many labs in the world measure phthalate levels in foods.

The independent lab that was contracted for this research, a Belgian outfit called VITO, already published one of the most cited phthalate-and-food peer-reviewed studies in 2012. So while the current study wasn’t peer-reviewed, it’s probably not a big deal.

The first rule of toxicology: the dose makes the poison

Just because something is a man-made chemical doesn’t mean it will hurt you, nor does being “natural” mean a compound is safe. Improperly-processed beans can kill you at even low doses, for example.

The issue of phthalates in food is a complicated one, as you can tell from these three examples of dosage studies.

1) Unplanned exposure: Taiwan

In 2011, Taiwan was the home to an unplanned experiment involving phthalates. Companies are not supposed to deliberately add them to foods and drinks, but over two months that spring, they were added to around 1,000 products in Taiwan, about a fifth of which were shipped to other countries. The good news? Phthalates don’t really build up in the body. The bad news? Some people had phthalate levels increase ten-fold, exceeding the tolerable upper intake set by food safety organizations. Unfortunately, nobody knows how long it takes to get health impacts from high phthalate exposure.

2) Unplanned chemical synergy: Polysorbate 80

Phthalates aren’t actually bound very tightly to plastics, so they can leach pretty easily, and interact with other chemicals. Polysorbate 80 is one of those chemicals. It’s used in a variety of foods as an emulsifier, enabling water and fat to combine easily. You might see it in some ice creams, especially cheaper brands.

It turns out that polysorbate 80 causes you to absorb around double the amount of DEHP, one of the main phthalates linked to health effects.

3) Unplanned widespread exposure for kids: the mac and cheese study

Boxed mac and cheese in one of the most widely sold packaged foods, and is a staple for many family dinners. Especially dinners for little kids. The current report found that powdered cheese in these boxes had more than four times higher phthalate levels than natural unprocessed cheeses. All the tested varieties contained high phthalate levels, including organic varieties.

What does this all mean? It’s pretty easy to get too much phthalate, and it’s pretty difficult to estimate how much you’ve ingested during yours (or your child’s) life. The reason estimation is tough is because ...

There’s A LOT more research to be done

You might think the solution is easy: eat fewer packaged foods, absorb less phthalates, easy peasy.

Researchers have already tried that a couple times, once with some success and once with it weirdly leading to HIGHER phthalate levels. What the heck?

You might be able to guess one of the culprits: dairy fat. The milk and cream in this study ended up having much higher phthalate levels than dairy fat in previous studies, which means that predicting phthalate intake can be rife with error. The other culprit was, strangely enough, coriander. A couple of the dinners that study participants ate had coriander-spiced chicken in them, and the coriander in this study happened to have sky-high phthalate concentrations.

The end result of this study was kind of astounding: subjects had 100 times higher phthalate levels than even the highest percentiles of phthalate in the general population. These levels went back to normal after the study, but it makes you wonder: could someone eat a fairly healthy diet, but have sky-high in phthalate levels just from a couple problematic packaged foods?

This problem is compounded by the unpredictable phthalate content of some foods: freezing beef lowers phthalate content, but freezing fish seems to increase it; cooking decreases phthalates in most foods except for vegetables, chicken has higher levels than other meats, and nobody knows which spices in which package types have high levels. Bread doesn’t have much fat in it, but was pegged as the leading source of phthalates in Belgian people.

We do know that dairy fat and cooking oils in plastic containers are susceptible to having high levels, and that yogurt has lower levels than butter and cream. That’s because foods that are higher in concentrated fat tend to store the fat-loving high molecular weight phthalates like DEHP.

If you live in the US, your government isn’t overly worried (yet?). European governments are much more worried.

Phthalates are approved by the United States FDA for use as plasticizers in food packaging and food processing materials. Over in Europe and China, government commissions decided in the late 2000s to limit the use of phthalates for those purposes.

This is partly due to differing regulatory attitudes, and partly due to incomplete and new research. Only in the past twenty years or so have scientists been able to accurately measure phthalate concentrations in humans. In the early 2000s, the first evidence started popping up linking prenatal exposure to phthalates with abnormal birth outcomes, and the research has been building in the past couple years.

Research on health effects will always be largely estimated from animal experiments, as you can’t randomize humans to eat large amounts of phthalates and see what happens after a few years. But over the past few years, we’ve gotten a good sense of phthalate levels in humans, and it’s not looking good.

Infants who eat a typical diet can easily exceed the EPA’s reference dose of phthalates, as can adolescents who eat a lot of dairy and meat. This isn’t good, as high exposures in little tikes has been linked to behavioral issues and allergic conditions. Adults can also overconsume phthalates given the right combination of foods, and high levels have been linked to lower testosterone production in men and endometriosis risk in women.

What should you do, given all this research? Consider these steps.

Step 1: Consider using glass more often

Glass containers are heavy, more expensive, and break more easily. But they don’t leach chemicals, and it may be worth switching to more glass over plastic (for both foods you buy in containers, and as vessels to store your leftovers).

Step 2: Don’t base your diet on packaged foods

There are a million and one reasons to avoid eating too much highly-processed packaged foods and snacks, and this is just one of those reasons. Remember that it takes practice to wean off of convenient and hyperpalatable foods … Rome wasn’t built in a day, and eating habits don’t change instantaneously either.

Step 3: Diversify your diet

Eating the same foods every day has some pros, like consistency of calorie intake, but toxicity potential is one of the cons. If you eat just a few of the high-phthalate foods on a consistent basis, toxicity loads can get quite high. Diversify, and enjoy the wealth of different foods modern life affords!

Step 4: Learn the precautionary principle, which is one of the foundations of public health.

“When an activity raises threats of harm to the environment or human health, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically.”

As an example, there was a supposedly safer phthalate called DINP that was being used as a replacement for DEHP. California recently classified DINP as a carcinogen, which the plastics industry really didn’t agree with. Who to trust, given all the studies on each side of the issue? Like most health-related decisions, it’s up to you, but it's wise to remember that humans don't fully understand what goes on in our bodies. Even the most well-published researchers don't, as important new discoveries come out each year.