Many of us are concerned about the food we put into our bodies. Is it organic? Where does it come from? What’s in it? And rightly so. But there are other things we put into our mouth on a daily basis. In fact, at least twice a day. Without even thinking about it. Toothpaste.

Which begs the question: why are we so concerned what we put into our stomachs, when we seem to have no care about the pasty substance we use approximately 49640 times during your life-time between the age of 2 and 70 (assuming that before or after you won’t have any teeth to clean)? I suppose it’s because few of us are aware of the fact that the mucus membranes inside our mouth are one of the most direct routes to our blood, our organs, our brain. More so than our stomach, where food needs to be broken down first. And it has about 90% absorption efficiency. Worried yet?

Here is a list of five ingredients that can be found in almost all brand name toothpastes, with very few exceptions. So whatever your favourite happens to be, take a look at the small print next time you brush and find out what exactly you are putting in your mouth.

1. Sodium lauryl sulfate

Maybe some of you still remember your elders threatening you to wash out your mouth with soap if you were to use that ‘bad word’ again? I do. Little did I know back then that all my Gran would have had to do is tell me to go and brush my teeth. Of course that would have been a much less intimidating threat, and in fact, she might not have even known herself.

Sodium lauryl sulfate, or SLS, is often listed as ‘surfactant’ or ‘dispersant’ if you take a close look at some toothpaste’s ingredients list. All it means is that it allows lowering the surface tension between two liquids as they mix, forming bubbles and stabilizing them. In simple terms it’s a detergent. The same you use to wash your dishes. It’s soap. And don’t be deceived by claims that SLS is better than SDS (sodium dodecyl sulfate), which has received bad press over the past years. It’s one and the same. Both are eye and respiratory tract irritants and allergens. And while not listed as such, when used in the laboratory to denature proteins, they are regarded as bio accumulative chemicals. Suggesting that you will develop a potential allergy to it over time and with continued use. Like I did.

2. Sodium saccharin and sorbitol

Sugar has become an increasing concern in our society. Diabetes and obesity are increasing steadily, especially among children. We now lean more often towards food and drinks that contain less or no sugar to curb our intake and that of our children. But do you also consider your sugar intake when it comes to your toothpaste? You should. After all, it’s a main ingredient and comes in one of two flavours: sodium saccharin or sorbitol.

Many of us are familiar with saccharine to sweeten coffee or tea. It was developed first in the 1870s and is made from coal tar. Yummy. It contains no caloric value and is not absorbed by our intestines. However, the sweet taste of saccharin has been suspected to still trigger a response from our hormone glands (also called endocrine system) and stimulate insulin production from the pancreas. The main effect of insulin is to transport sugar in the blood stream to various body tissues that can use it for energy. Without any actual sugar entering the blood stream, when ingesting an artificial sweetener such as saccharin, insulin has nothing to bind to. Over time this void stimulation could decrease your insulin sensitivity when you actually do eat sugar (requiring you to eat more to elicit a response by your glands) and increase your risk for developing diabetes.

Sorbitol, on the other hand, is a simple sugar substitute and does provide dietary energy. At least that will give our insulin something to transport. Better? Not really. Sorbitol is suspected to aggravate irritable bowel syndrome and similar digestive conditions, which are very common today, even in small amounts.

3. Triclosan

In the past decade we have become literally obsessed with everything antibacterial. Antibacterial hand soaps, wipes, dishwashing liquid, and shower gels. You name it and it will most likely exist in its antibacterial form. There are even antibacterial children’s toys. And yes, there is also antibacterial toothpaste. Triclosan is the chemical most commonly used as an antimicrobial ingredient. In toothpaste it is added to fight gum inflammation. It’s often paired with PVM/MA copolymer, a water fixative found in hairspray, that causes it to stick to your teeth and gums, rather than getting rinsed away.

Yet while triclosan is so prevalent throughout our households it is even more so than you might have ever thought. The US Centers for Disease Control and Prevention found the chemical present in the urine of 75 percent of Americans over the age of 6. How so? Triclosan is bio accumulative; meaning with every dose you put into your mouth or onto your skin, some of it will stay behind and become absorbed into your body. And often the doses are too high to begin with. While Health Canada limits the levels of triclosan in toothpaste and mouthwash to 0.03%, there are several commonly used pastes out there that contain levels of 0.3%.

It fights bacteria. So what’s the problem? The EPA (Environmental Protection Agency) lists triclosan as a pesticide and the FDA suspects it to alter hormone regulation based on studies in rodents. But beside that the use of triclosan also contributes to bacterial antibiotic resistance. In light of that, several countries, including Canada, are actively seeking to ban the ingredient.

4. D&C Yellow, D&C Red, FD&C Green and FD&C Blue

“The red stripe helps fight plaque and protects gums, the white stripe has fluoride to fight decay, and there’s a blue stripe for fresh breath.”

Familiar? It’s a famous advertising jingle for a well-known brand toothpaste. Over the years companies have worked out strategies to make toothpaste more appealing through its cool colors or new gimmicks represented by them. Yet the colors meant to brighten up our daily brushing routine are much less pretty than they look. Made from coal tar, a mixture of many chemicals derived from petroleum some of them were shown to have the potential to cause cancer when applied to the skin. So what could be the consequences if put into our mouth?

In addition they are often contaminated with low levels of heavy metals or combined with aluminum substrate. Aluminum compounds and many heavy metals are toxic to the brain. Some colors are not approved as food additives, yet they are still used in personal care products that may be ingested, like toothpaste. In the U.S. color naming system, “FD&C” indicates colors approved by the FDA for use in foods, drugs, and cosmetics, “D&C” colors are not approved for use in food. But then again, does toothpaste count as food?

5. PEG-40 Hydrogenated Castor Oil

The first time I bought castor oil, the woman in the shop gave a me concerned look and asked “You know it’s only meant to be used on the outside of your body? Not for cooking or ingesting any other way. Right?”

I knew but was still happy she seemed concerned, as I did feel a little uneasy about using castor oil at that point. Castor oil is obtained from castor seeds, which contain ricin, an extremely toxic protein removed during cold pressing and filtering, rendering the oil fairly harmless. For the outside of your body.  So why is found in toothpaste as PEG-40 hydrogenated castor oil?

PEG-40 hydrogenated castor oil means that the oil has been ethoxylated, a process in which ethylene oxide, a petroleum based chemical, is added to alcohols and phenols to produce surfactants, often with the carcinogenic 1,4 dioxane as a by-product. A surfactant?  An emulsifier, foam booster, cleansing agent. And that’s why it’s in your toothpaste. The one that you put in your mouth, on the inside of your body.

We are often led to believe that using chemicals like the ones listed above reflect progress. That they allow us to live healthier than our ancestors, even our grandparents, did. Yet do they really? My grandmother was born in 1920 and for the majority of her life used simple products to clean her teeth. A combination of salt and sodium bicarbonate, mixed with water into a paste during her childhood and the War, and later on a little more sophisticated mixtures, which were still simpler than the mélange of chemicals found in toothpaste today. And you know what? She lived to the impressive age of 87 with her own teeth intact and well. For me she was a shining example that with simple yet thorough care you can keep your mouth healthy without inflicting harm to the rest of your body.