What’s in a can of olives? Most people expect just one ingredient: olives. Maybe some water or salt at the very most. But pick up an actual can, and you’ll probably find other things like ferrous gluconate or citric acid on the label as well. It's nothing compared to the huge list of tongue-twisters on the back of a TV dinner, but even some Paleo-friendly foods like coconut milk or canned broth can raise a few eyebrows with unfamiliar ingredients. What are these things, and can they really be safe?
If you Google pretty much any common food additive + cancer, you’ll come up with at least one person who claims to have found a link, but all the recent hype about red meat and cancer proves that it’s very important to analyze these connections carefully, and determine whether they’re actually based on science, or on scare tactics. If the only sources for claiming something is dangerous are studies on rats and mice, make sure to check the concentrations used in the studies. As discussed in the article on salt, feeding a rat an extreme amount of anything will make it sick.
Also, make sure to distinguish between preservatives and the foods they’re in. A high intake of preservatives usually indicates a high intake of nutrient-poor processed foods, so if the connection is as vague as “people who eat more X get more cancer,” there are probably a lot of other factors at work besides that one particular additive. In these cases, an overall malnourishing diet is likely to be doing much of the damage, so it’s not a serious concern for Paleo dieters.
The list below is an alphabetical guide to some of the most common eyebrow-raising ingredients in minimally processed Paleo foods. It completely ignores additives used only in non-Paleo foods, and it shouldn’t even be an issue for most of your shopping cart. If everything you buy has at least one of these ingredients, you’re probably not eating Paleo to begin with.
On the list, if something is marked as “probably” safe, it means "probably safe for a healthy person eating a nutrient-dense Paleo diet, without any special allergies or intolerances." Plenty of people have individual sensitivities to these chemicals, so if you feel better or healthier avoiding even the “safe” additives, by all means do it. Even if it’s just the placebo effect, feeling good about your food can have a huge impact on digestion and health. The best diet is the one that works for you, so take the list as a guide and do your own experiments from there.
Found in: Butter and cheese
What does it do? Annatto gives butter and cheese an attractive yellow color.
Is it safe? Probably, unless you have an allergy. Annatto is a derived from the fruit of a tropical tree called the achiote; it doesn’t add anything nutritionally but it’s also not a major gut irritant. Even in rat studies, where the rats were fed absurd concentrations of annatto, researchers couldn’t find much of an effect. Some people have severe allergies to annatto (as with any other substance), so those people should go for products without it, which aren’t hard to find. Just make sure you aren’t fooled by the color of your butter into thinking it has more nutrients than it does: annatto only imitates the deep yellow color of real grass-fed butter; it doesn’t contain any of the Vitamin K that makes pastured butter so nutritious.
Ascorbic Acid, Ascorbyl palmitate
Found in: Cured meats
What does it do? It’s an antioxidant.
Is it safe? Yes; it’s just Vitamin C. In fact, it’s even beneficial, because it helps inhibit the conversion of nitrites to nitrosamines (see nitrites, below).
Autolyzed Yeast Extract
Found in: Store-bought broth
What does it do? It brings out savory flavors.
Is it safe? Nobody knows! The biggest health concern regarding autolyzed yeast extract is that it contains MSG. Some food manufacturers claim that the MSG in autolyzed yeast extract is “naturally occurring,” but it’s basically the same thing – see MSG.
Benzoate (sodium benzoate)
Found in: Fruit juice, carbonated drinks, pickles
What does it do? It’s an antimicrobial agent to prevent bacteria from growing in the foods.
Is it safe? Probably not. Sodium benzoate by itself is not dangerous, but when it combines with Vitamin C, it can form benzene, which is a recognized carcinogen. The food industry likes to point out that we also get benzene from breathing polluted air and drinking polluted water, but this doesn’t mean we shouldn’t eliminate it where we can! Fortunately, there’s not a lot to worry about for the Paleo crowd, since by far the largest source in the modern diet is soft drinks.
BHA (Butylated Hydroxyanisole) and BHT (Butylated Hydroxytoluene)
Found in: Fatty foods like nuts and lard
What do they do? BHA and BHT are antioxidants.
Is it safe? Possibly. Some studies show that very high amounts of these chemicals cause tumors in rodents, but others failed to establish the same correlation at normal levels in humans. Other studies even suggest potential health benefits. But the major concern with BHT from a Paleo standpoint isn’t that it’s harmful in itself, it’s that it indicates a processed, low-quality source of fats. Avoid it as a marker for unhealthy fats like trans fats, or fats that have been poorly treated, not on its own.
Found in: Pickles, canned tomatoes
What does it do? It’s a preservative – it’s basically salt (one of our oldest known preservatives) but a kind of salt that doesn’t contain sodium, which pleases the USDA and everyone who buys into their misguided recommendation to reduce dietary salt at all costs.
Is it safe? Yes. It’s just salt. It’s also used on roads as a de-icer, but so is regular salt. If you inhale it, it’s toxic (just like regular salt), but using it as a preservative is fine.
Found in: Dairy products, non-dairy alternatives (coconut milk, rice milk, soy milk, etc.), processed lunch meats, and some supplements
What does it do? It’s a thickener, and especially used to replace fat.
Is it safe? Probably not.
Just from rat studies, you might think there's nothing to worry about. The WHO has established an Acceptable Daily Intake of carrageenan as 0-75 mg/kg bw. Average daily intake is approximately 250mg/person/day, which falls well toward the low end of the “safe” spectrum. In order to show any risk to humans, the studies supposedly showing a high risk would have to approximate this level. The animal studies linking carrageenan to intestinal inflammation and leaky gut don’t pass this sniff test. For example, in rats, an administration of either 9,690 mg/kg bw or 3876 mg/kg bw made colon tumors worse: no kidding! This paper gives a useful overview of the problems with the rodent studies. But that doesn’t mean the stuff is good for you.
In human studies, some evidence shows that carrageenan increases intestinal permeability. A study on isolated human intestinal cells found that carrageenan was inflammatory, and suggested it as a factor in the development of inflammatory bowel disease. In another study on isolated intestinal tissue, researchers found that carrageenan had a significant effect on the cells, although they didn’t link it to any specific disease.
Studies in real live humans would be better, but since these are obviously out for reasons of medical ethics, isolated human tissue is a lot more convincing as an experimental subject than rats. It’s probably safest to avoid carrageenan, at least until we have more research.
Found in: Balsamic vinegar
What does it do? Caramel color is nothing but dye – it doesn’t change the taste of the vinegar at all.
Is it safe? Probably. Caramel color is produced by an extreme form of the same browning reaction that gives you the crispy golden skin on a roasted chicken or grill marks on a steak (the same process that creates AGEs). As well as heat, the process usually also uses various forms of ammonia and sulfites. One study from the Center for Science in the Public Interest found that the resulting coloring agents were carcinogenic in mice, but this study used extremely high amounts that no normal human would ever ingest. Another study also using enormous amounts found that the worst problem the treated rats studied was diarrhea.
On a Paleo diet, caramel color just isn’t a big concern, because the dose is far too small. You’d have to drink a thousand cans of soda a day to get the level of caramel color fed to the mice. In a splash of balsamic vinegar, there’s really nothing to worry about.
Found in: Canned products
What does it do? It’s an antioxidant, it preserves the color of the product, and it keeps the pH low.
Is it safe? Maybe. Citric acid is a naturally-occurring substance that your body needs and produces on its own, but that doesn’t necessarily safe as an industrial additive. Some citric acid is made from corn, and some isn’t – and there’s no way to know unless you call the manufacturer. Corn-based citric acid contains some MSG (see the entry on MSG). Unless you have a severe corn allergy or MSG sensitivity, it’s probably safe.
Found in: Unsalted butter
What does it do? Butter flavoring.
Is it safe? Probably. Diacetyl is most famous for causing “popcorn lung” in people who eat a lot of microwaved popcorn and other foods with artificial butter flavoring. But it’s only really dangerous if you inhale it. So microwaving a bag of Orville Redenbacher and then taking a deep breath of the air out of the bag is a bad idea, but popcorn isn’t Paleo anyway. It’s very unlikely that a normal use of unsalted butter would cause you to inhale enough to cause any problems.
That said, if you do want to avoid diacetyl, beware: manufacturers aren’t required to list it on the label, so they often hide it under very vague terms like “natural flavors.” Check for a butter that contains only ingredients you recognize.
Found in: Canned foods
What does it do? EDTA is a chelating agent. It binds to heavy metals to remove them from the food – for example, if the food has picked up any heavy metals during processing.
Is it safe? Probably. The real risk with EDTA is of creating mineral deficiencies by preventing your own body from absorbing those minerals, especially zinc. However, as far as we can tell from rat studies, this doesn’t appear to be a significant risk if you’re eating an adequate amounts of minerals. Rats fed a nutrient-deficient diet suffered from EDTA consumption, but rats fed an adequate diet did not, even at large doses. In the context of a nutrient-dense diet, there’s nothing to worry about.
Found in: Olives
What does it do? It's a black coloring.
Is it safe? Yes. It’s basically an iron supplement. Unless you have another reason not to be taking iron supplements, it’s fine.
Found in: Vinegar
What does it do? It’s a flavoring.
Is it safe? Yes – it’s just concentrated grape juice.
Found in: Coconut milk
What does it do? It’s a thickening agent. It prevents the milk from separating, which isn’t necessary to keep the food fresh, but it’s more attractive from a marketing perspective.
Is it safe? For most people. Guar gum is made from guar beans, and many people have trouble digesting the insoluble fiber from the beans. If you have IBS or FODMAPs sensitivity, try an elimination diet for 30 days to see if it helps. Otherwise, it’s safe.
Hydrolized Vegetable Protein
Found in: Soup mixes
What does it do? It’s there as a flavor enhancer.
Is it safe? No. First, it’s usually made of soy. Second, it contains MSG (see the entry on MSG for more details).
Inosinic Acid (disodium inosinate, dipotassium inosinate, calcium inosinate)
Found in: Savory protein foods (broth, sausages, cheese, and canned soup)
What does it do? It’s a flavor enhancer; it does basically the same thing as MSG (doesn’t provide any flavor of its own but increases the flavors of other things).
Is it safe? Probably. There haven’t been a lot of studies on this one, since MSG steals all its thunder on the flavor-enhancing front. It seems to be pretty harmless, but it’s often used in conjunction with MSG, so be careful when you see it on the label.
Found in: Salad dressings
What does it do? It’s a bulking agent; basically, it’s just fiber.
Is it safe? Yes, unless you have trouble digesting FODMAPs.
Found in: Olives, cheese, butter
What does it do? It’s a preservative that helps regulate the pH of a food.
Is it safe? Yes. Lactic acid is a byproduct of the digestion of lactose by bacteria. It’s what gives kefir its typical tangy taste – all the lactose has been fermented into lactic acid.
Soy Lecithin (not to be confused with soy lectins)
Found in: Chocolate
What does it do? It’s an emulsifier (keeps the fat and the non-fat in a food from separating).
Is it safe? Lecithin that’s not from soy is a perfectly safe and even necessary as a vital source of choline. It’s in all kinds of natural plant and animal foods. But most of the lecithin you’ll see on grocery store packages isn’t from egg yolks, it’s from soy (because soy is very cheap). Soy lecithin isn’t healthy, but the tiny amounts found in chocolate as an occasional indulgence also aren’t likely to cause any serious harm, unless you’re extremely sensitive to soy.
Found in: Meat products, especially bacon and canned fish.
What does it do? It’s an artificial barbecue flavor.
Is it safe? Probably not, and it’s not clear why anyone would want to eat a vegan bacon flavoring when you could have real bacon. Liquid smoke is basically the result of trapping smoke from woodchips in a liquid. Studies on rats, mice, and pigs found no ill effects on the weight or organs of the animals, but a recent study from the European Food Safety Authority raised concerns about the genotoxicity of one type of liquid smoke at levels that actually come close to normal human consumption.
Monosodium Glutamate (MSG)
Found in: Salad dressings, canned soup, Asian food
What does it do? MSG is a form of the naturally occurring chemical glutamate, which doesn’t taste like anything by itself, but enhances other flavors, especially savory flavors like meat. Glutamate in its natural form is the source of the flavor umami, found in vegetables like mushrooms and tomatoes.
Is it safe? Nobody knows! The evidence on MSG is one huge mass of conflicting studies, scare tactics, anecdotal evidence, food industry dishonesty, and unconvincing government reassurances. Many people claim to have a serious sensitivity to MSG in foods (the “Chinese Restaurant Syndrome”), but clinical studies have failed to find a clear or consistent link. Giving human subjects enormous amounts of MSG by itself frequently produces mild symptoms, but a normal amount of MSG in food does not. Similarly, injecting rodents with MSG causes all kinds of problems, but humans don’t shoot it into our veins, so these studies are of very limited utility (just because something doesn’t belong in a rat’s bloodstream doesn’t mean humans shouldn’t eat it).
Another frequent condemnation of MSG is the link to obesity, but here the evidence is conflicting here too. Researchers in rural China (where people eat few modern processed foods but frequently cook with plain MSG) found that MSG intake was a strong predictor of obesity, even when controlling for other variables like total calorie intake. But another study found no relationship. A further study found that MSG reduced satiety in the short term, but increased it in the longer term. Yet another study found that obese women tasted MSG differently than normal weight women, and the obese women needed more of the MSG to get the same flavor hit. It’s possible that the overweight people in the first study ate more MSG because they were overweight, not the other way around.
Even among natural foods/Paleo advocates, the consensus isn't solid. A Paleo diet eliminates almost all sources of MSG anyway, since it’s mostly found in Asian restaurant food and pre-made packaged meals. You might find it in store-bought broth or canned soup. Until further research can actually confirm or deny the relationship, avoiding MSG can’t do any harm, but small amounts in Paleo-friendly processed foods aren’t likely to have huge consequences for non-sensitive people, either. Try a 30-day elimination test and re-introduction to see if you react to it.
Note that many people have strong negative associations with MSG, so food manufacturers try to hide it. If you are interested in avoiding it, also avoid: anything “glutamate,” anything “hydrolyzed,” protein isolates or concentrates, and autolyzed yeast. Also beware anything with “chicken broth” or “vegetable broth” as an ingredient; these often contain one or more of the other forms of MSG.
Found in: Cheese and sausages
What does it do? It’s an antifungal preservative.
Is it safe? Probably. Natamycin isn’t absorbed from the gut, and doesn’t seem to affect the gut flora at normal levels from food. Nausea, vomiting, and diarrhea were observed in human subjects at levels approximately equivalent to 10kg of cheese or 20kg of sausages in one sitting – not exactly a realistic intake.
Found in: Dairy, meat, and egg products, canned foods, salad dressings
What does it do? It’s an antibacterial that prevents food from spoiling.
Is it safe? Probably. It doesn't seem to affect gut flora or produce antibiotic-resistant germs at the concentrations used in food.
Nitrates and Nitrites: see Sodium Nitrate
Found in: All kinds of products – canned foods, spice mixes, condiments like mustard and vinegar, and anything else that comes in a box or carton can have natural flavor.
What does it do? It adds flavor, any kind of flavor. Anything derived from something naturally occurring is a “natural flavor,” and “natural flavors” can actually be chemically identical to “artificial flavors;” the only difference is that the chemicals in the “natural” version came from a plant or animal, and the chemicals in the “artificial” version came from a lab.
Is it safe? It depends. MSG is a “natural flavor,” and so are other disgusting additives like castoreum (a vanilla flavor made from the anal sacs of beavers). Then again, “natural flavor” could be as simple as salt and pepper. Without calling the manufacturer of the food, there’s no way to actually tell what “natural flavor” is, so unless you’re willing to do some research, it’s a safe bet to avoid it.
Found in: Meat
What does it do? It’s a meat tenderizer
Is it safe? Yes; it’s just an enzyme that comes from papaya. Unless you’re allergic to it (as some people are), there’s no danger.
Phosphates, Phosphoric acid
Found in: Meat (especially cured meat), cheese, dairy products, and egg products
What do they do? They’re meat tenderizers and make products more attractive (for example, they help cheese keep its shape).
Are they safe? Probably not. Unlike naturally occurring phosphorous, artificial phosphate is very absorbable in the gut, and has dangerous consequences for cardiovascular and kidney health. One study found that these additives significantly increased the phosphorous content of the food, which is problematic for kidney dialysis patients, who often struggle with serious complications from too much phosphorous. Too much phosphorous also contributes to vascular calcification (plaque in the arteries), so it’s a serious heart risk.
Found in: Anything with a salty flavor (broths, soups, etc.)
What does it do? It’s a salt substitute.
Is it safe? Probably. Like calcium chloride (see above), it’s basically a salt flavoring without sodium; it’s very dehydrating and toxic if overdosed, but small amounts found in food are safe.
Sodium Benzoate: see Benzoates
Found in: Meat and meat products
What does it do? It’s a preservative and helps regulate the pH of foods.
Is it safe? Yes – if injected it can cause serious problems, but that’s not a concern for food additives.
Found in: Lemon juice, canned tomatoes, fruit juices
What does it do? It’s a preservative and an antioxidant.
Is it safe? Maybe. See Sulfites.
Sodium Nitrate or Sodium Nitrate
Found in: Processed meats (bacon, hot dogs)
What does it do? Nitrates and nitrites are coloring chemicals and antibacterial agents.
Is it safe? Probably. This might come as a surprise to people used to scouring the bacon selections to find ones cured without nitrates, but in fact the hype about nitrates and nitrites is probably overblown. First of all, it’s important to understand that nitrates and nitrites aren’t the same thing. Nitrates are found in plants – in fact, 80% of our total nitrate intake comes from vegetables. Some plants provide nitrites as well, and the human body can also produce them internally.
The real danger isn’t in the nitrates or nitrites themselves, but comes when they’re heated up, producing nitrosamines. Nitrosamines are carcinogens, but there’s a quick and easy way to prevent them from forming in the first place: antioxidants like Vitamin C. This is why you’ll see “ascorbic acid” (Vitamin C) on packages of cured meats. Processed meats have been linked to cancer in epidemiologic studies, but this is more likely because processed meat is a marker for an unhealthy lifestyle in general (even these studies note that it’s correlated with lower income and higher rates of smoking, for example). Bacon isn’t an ideal staple food in general, but as a treat or a luxury food, it’s not going to give you cancer.
On the topic of nitrates and nitrates, it’s worth noticing that even products with “no added nitrates or nitrates” aren’t free of these chemicals. Instead, these products use celery, which is a natural source of sodium nitrate.
Sodium Phosphate: See Phosphates
Sorbates (sorbic acid, sodium sorbate, potassium sorbate, calcium sorbate)
Found in: Pickles, cheese, wine, dried fruit
What does it do? It’s an antimicrobial preservative.
Is it safe? Probably. Some people who are very sensitive to sorbates have allergic reactions to them, but this is fairly rare and the anecdotal evidence is not backed up by research.
Soy Lecithin: See Lecithin
Found in: Condiments, store-bought canned foods and broths
What does it do? “Spices” could mean any kind of spice.
Is it safe? Yes, unless you have an allergy to a specific type of spice. If you’re allergic, call the manufacturer first to check.
Sulfites (sulfur dioxide, sodium sulfate, sodium and potassium bisulfite, metabisulfites)
Found in: Dried fruit, vinegar, and wine
What does it do? Sulfites are color preservatives (for example, to stop cut fruit from going brown) and antioxidants.
Is it safe? That depends. Some people have extremely severe sensitivities to sulfites, including anaphylactic reactions as dangerous as the most extreme peanut allergies. Sulfites occur naturally in several kinds of food (including wine), and people who are sensitive to added sulfites are generally sensitive to these natural ones as well. This is a particularly sneaky food allergy, because naturally occurring sulfites are often unlabeled, so it requires a lot of research to maintain a sulfite-free diet.
The best way to determine if you have a sulfite sensitivity is an elimination diet. Cut out sulfites (including dried fruit and wine) for 30 days, and then try reintroducing them. If you don’t react to them, they’re probably fine.
Textured Vegetable Protein
Found in: Processed meat products.
What does it do? It’s a meat extender (it gives manufacturers a less expensive way to bulk up a meat product)
Is it safe? No; it’s usually made from soy, but can also be from wheat or oats – eat real meat instead!
Found in: Meat and seafood, especially the meat in restaurants
What does it do? It’s glue for meat; it’s used to do things like stick several pieces of meat together into “one” steak.
Is it safe? No, but not because of the transglutaminase itself. Gluing scraps of meat together poses a serious risk of bacterial contamination, especially if you like your Frankensteak anything less than well-done. In a real steak, the inside is sterile (it’s the outside that harbors bacteria), so a rare steak isn’t dangerous. But if the “steak” is actually a conglomeration of random meat scraps, the uncooked inside could be full of bacteria like E. coli – not a great condiment to your dinner.
Found in:Coconut milk, sauces, salad dressings
What does it do? It's a thickening agent and an emulsifier (stops ingredients from separating)
Is it safe? Maybe. Xanthan gum is a by-product of fermentation. When a certain species of bacteria ferment simple sugars, they produce a kind of sticky, gooey gunk that's dehydrated into a powder and then re-hydrated into a gum. This is a little gross to think about but nothing alarming in itself. However, the "simple sugars" often take the form of corn, wheat, and soy (and you won't know unless you actually get in touch with the manufacturer and ask). Allergies to these substances can be triggered by xanthan gum. If you don't have a severe allergy or gluten intolerance, a little bit of xanthan gum isn't going to destroy your health, but guar gum is a better alternative.