As we naturally take stock of what we’re putting into our bodies at the start of the year, our list of “no’s” is likely to be completely individual. But we know for certain that these four ingredients to avoid are worth a place on that list!
I know the internet is rife with stories about “toxic” ingredients hiding in our bone broth, radiation in fish, and assertions that fruit will kill you. The fact is, most of these stories just aren’t backed by scientific facts (see “Should We Be Worried About Radiation From Fukushima?”, “Bone Broth Risks: Skim The Fat!”, “Why Fruit is a Good Source of Carbohydrates”)!
What’s more, there are plenty of cut-and-dried examples of chemicals and additives that solid scientific research indicates are ingredients to avoid in 2018. In this post, I’ll focus on four great examples and explain why cutting them is worth your time.
Artificial food dyes are fairly easily avoided on a whole-foods diet, but does your occasional M&M indulgence mean more than a nasty sugar crash? Maybe!
Synthetic food dyes are a class of colorings derived from petroleum, and are used to by food manufacturers (or even chefs) to alter or enhance the color of foods. Our intake of food dyes is now five times as much as it was 60 years ago, and sometimes those dyes end up in less-than-obvious places (like sausage coatings and orange peels, which are sometimes colored with Citrus Red No. 2, both of which may be considered Paleo foods). You may even be exposed in OTC medications!
The FDA has banned the use of many dyes over the years due to evidence of harm. But there are multiple lines of evidence showing some of those still approved for use should be of concern.
In rodent studies, a number of artificial dyes have been shown to induce malignant cell transformation, increase tumor incidence, damage DNA in the stomach and colon, and increase total mortality. For certain common dyes (like Red 2, Red 40, and Yellow 5), DNA damage in mouse gastrointestinal organs happens even at low doses close to the acceptable daily intake.
Some of the most widely used food dyes contain benzidine, a chemical carcinogen that doesn’t occur in nature. Although the FDA tests for levels of free benzidine in food dyes and factors that into safety assessments, bound benzidine isn’t documented by FDA tests. So, consuming certain food dyes may result in higher exposures to this carcinogen than generally believed, and the FDA’s acceptable daily intake levels could be higher than they should be.
In 2010, the Center for Science in the Public Interest (CSPI) published a report called “Food Dyes: A Rainbow of Risks” that questioned the safety of dyes still approved for human consumption. The report noted that along with seven of the FDA-approved dyes contributing to cancer in lab animals, four dyes are linked to uncommon but severe allergic reactions, yellow 5 has been shown to exacerbate asthma in certain people, and some studies suggest dyes may contribute to behavioral problems including impaired performance in hyperactive children, increases in aversive behavior, ADHD, restlessness, and sleep disturbance.
As of right now, the FDA doesn’t require food dyes to be tested for developmental neurotoxicity, so their safety for growing children is a question mark. In other words, our existing studies on food dyes aren’t strong enough to confirm their safety.
Since there’s no nutritional reason to keep food dyes on our plates, and plenty of food-based alternatives exists for times when you just need to color your dairy-free frosting, I think it’s worth steering clear of food dyes and placing them on our list of ingredients to avoid.
For more including references, check out “Food Dyes: What’s the Big Deal?”.
Ok, so glyphosate isn’t something you’re likely to find on an ingredient label. But your exposure might be high simply because you’re eating genetically-modified foods like corn, soy and canola that were treated with this pesticide. The evidence here isn’t cut-and-dry, so it’s worth investigating (for a full exploration and references, check out “Glyphosate (Roundup) as a Cause of Celiac Disease”) !
Glyphosate is a broad-spectrum herbicide that can kill both grasses and leafy weeds. It works by inhibiting an enzyme (5-enolpyruvylshikimic acid-3-phosphate synthase, or EPSP synthase) in plants that’s needed to synthesize the amino acids tyrosine, tryptophan, and phenylalanine (which are essential for plant growth). In the US, glyphosate has been used for over 40 years and is used mostly to kill weeds that interfere with agricultural crops (typically corn, soy, and canola).
Scientists investigating causes of celiac disease have theorized that Glyphosate may be to blame. Celiac disease is closely linked with changes in the gut microbiome and the integrity of the intestinal barrier, and because genetics alone can’t explain why more people are developing celiac disease than ever before, some scientists have looked to environmental exposures (especially ones that have changed or increased during the last century) as a possible explanation for celiac disease rise.
A 2013 paper makes the case that glyphosate, the active ingredient in Monsanto’s Roundup, is to blame. It points to digestive problems including microbiome imbalances, enzymic inhibitions, mineral chelation and amino acid depletion, and increased health risks like cancer and infertility seen in fish exposed to glyphosate. While the the authors concluded glyphosate appears to make wheat more immunogenic, the paper garnered criticism for lacking a sound scientific basis, for misrepresenting certain data, and for mistaking correlation for causation.
I just returned from a conference where I was able to see new unpublished data further supporting the link between glyphosate and celiac disease (and even non-celiac gluten sensitivity). The data convincingly showed that glyphosate magnifies the zonulin released in response to gluten (in everyone, but of course we know that celiacs and others with the HLA-DQ2 and HLA-DQ8 gene variants already release exaggerated amounts of zonulin in response to gluten consumption) through two mechanisms! I will, of course, be writing a detailed article once this exciting new research in published. (And for more on this mechanism, see What Is A Leaky Gut? (And How Can It Cause So Many Health Issues?) and Gluten Cross-Reactivity: How your body can still think you’re eating gluten even after giving it up.)
So, where does that leave glyphosate-treated foods (and chemically-treated crops in general)?
We know that dietary exposure is sufficient for measurable amounts to get into our bodies. And, we know that there are multiple mechanisms through which glyphosate may negatively impact our health. However, many more studies need to be conducted before we conclusively link glyphosate to celiac disease.
But, while we wait for more relevant research to be conducted, there’s no harm in avoiding wheat and in choosing, when possible, food grown without the use of aggressive herbicides and pesticides! All things considered, it’s probably best to place glyphosate on our list of ingredients to avoid.
Processed vegetable oils are unsaturated oils extracted from seeds like soybean oil, corn oil, sunflower seed oil, cottonseed oil, and canola oil, just to name a few. Vegetable oils require extensive processing that could include mechanical extraction, high heat, industrial chemicals, deodorization, and toxic solvents. Let’s explore why they land on my list of ingredients to avoid in 2018!
Some plant-based oils are totally fine (like extra virgin olive oil [see “Olive Oil Redemption: Yes, It’s a Great Cooking Oil!”], avocado oil, macadamia nut oil, and coconut oil) because they can be cold-pressed, require far less processing, retain more micronutrients and antioxidants, and have a more beneficial fatty acid profile. On the flip side, processed vegetable oils are harmful for a few major reasons.
First off, the predominant fat in processed vegetable oils is omega-6. Most people eat way more omega-6’s than required, especially relative to our omega-3 intake, stirring up all kinds of inflammatory trouble.
Ideally, the ratio between omega-6 and omega-3 fats should be close to 1:1, but the ratio in Western diets is closer to 16:1! We owe a lot of that to processed vegetable oils. In fact, between the years 1909 and 1999, the US consumption of soybean oil alone increased 1000-fold! That led to a huge spike in the percent of our daily calories that come specifically from omega-6 fats.
Studies have linked high intakes of omega-6 (and a high ratio of omega-6 to omega-3) with a wide range of health problems, including certain cancers, cardiovascular disease, inflammatory diseases, osteoporosis, autoimmune disease, metabolic dysfunction, and obesity.
Another problem with highly unsaturated oils is their susceptibility to oxidation. Polyunsaturated fats are prone to reacting with oxygen, which can happen during cooking, storage, or in our bodies. While consuming already-oxidized oils is bad, oxidation of fats inside our body is also highly problematic, and may contribute to cancer. Monounsaturated and saturated fats are more stable, safer choices, and avoiding vegetable oils is a great place to start.
For more details including references, check out “Why Vegetable Oils Are Bad.”
Artificial Trans Fats
Most of us steer clear of trans fats, one of the most fortunate casualties of the anti-fat movement we’ve seen over the last 30 years. Unlike many fats, trans fats belong squarely on that list (see “Saturated Fat: Healthful, Harmful, or Somewhere In Between,” and “Carbs Vs. Fat Vs. Protein: Insights from Hunter Gatherers”)! But what makes these often-added fats so detrimental to our health?
Trans fats are formed by taking a polyunsaturated oil like soybean oil and injecting it with hydrogen to make it more solid, a process called hydrogenation. Because of their texture and long shelf life hydrogenated oils were used extensively by food manufacturers to make cheap, shelf-stable products. The highest levels of trans fats are found in margarines, processed snack foods, frozen dinners, commercial baked goods, and fast food.
In numerous studies, trans fats have been linked to higher LDL cholesterol, lower HDL cholesterol, and higher inflammation. In mice, trans fats have been shown to reduce the responsiveness of a growth factor called TGF-beta-1 that helps control the growth, proliferation, differentiation, and apoptosis of cells. Population studies consistently link higher consumption of trans fats directly to heart disease. And, some research shows a link between trans fats and diabetes! Several studies have even suggested that trans fats could raise the risk of certain cancers!
The good news is, trans fats are no longer “generally recognized as safe”. Within three years of this FDA ruling (June 16th, 2015), all food prepared in the United States must not include trans fats, unless specifically approved by the FDA.
However, there are actually other forms of trans fat that occur naturally in meat and dairy, and their health effects are much different than the trans fats in vegetable oils. The trans fats produced by ruminants have a slightly different chemical structure than industrial trans fats, and as a result, behave differently in the human body.
Unlike the partial hydrogenation process used with industrial oils, ruminants (like cows and sheep) have specific gut microbes that form trans fats through biohydrogenation. Ruminant trans fats don’t appear to raise cardiovascular risk factors at normal levels of intake. Conjugated Linoleic Acid, or CLA, found in ruminant fat may actually help improve glucose tolerance, facilitate fat loss, protect against certain cancers, and in most studies, has either a neutral or protective effect against heart disease! For more on CLA, check out Goat Milk: The Benefits of A2 Dairy.
So as you can see, trans fats land squarely on my list of ingredients to avoid in 2018. Luckily, it’s pretty easy to avoid artificial trans fats AND consume naturally-occuring, protective animal fats on the Paleo diet. Can you tell I’m a fan?
For more on trans fats, including references, check out “Trans Fats: What Are They, and Why Are They Bad?”.
So there you have it — the scientific antidote evidence to back up four ingredients I HIGHLY recommend avoiding in the New Year. With a Paleo diet, it’s easy to focus on best choices above those ingredients to avoid which can potentially harm our health!