Preventing Tooth Decay Begins with a Healthy Diet

Plus other tips for great dental health
adolescent girl with a beautiful smile
Darren Baker/

Tooth decay was something I thought I knew well how to prevent, so I was stunned when my five-year-old daughter’s first molar was so rotten that she needed to have it replaced with a crown. We eat well, she is rarely exposed to sugar or even juice, and she is (forced) to brush and floss regularly. She was sedated and numbed and experienced days of pain. I was forced to reconsider what I thought I knew about children’s dental health. It turns out that some conventional practices we accept as dental health solutions are questionable, but the most powerful weapon against tooth decay is food.

What’s at the root of tooth decay?

According to Dr. Roger Lucas, DDS, a pediatric dentist in Seattle and founder of, tooth decay in our children has become a “public health crisis” with an especially staggering rise in cavities in two- and three-year-olds. Moreover, he states that 40% of kids will have a cavity before their sixth birthday.

Both parents and dentists seem to have numerous theories as to why cavities are on the rise, even in health-conscious families. But the truth is that tooth decay is multi-faceted, says Dr. Michael Schecter, partner at Schecter Dental, a Toronto-based holistic dental practice focused more on prevention than just the “drill and fill” model of dentistry.

What’s lost in this typical modern model of dentistry is a commitment to research and prevention, thus making it very difficult to know exactly what is at the root of our children’s tooth decay. In particular, it makes it very hard for dentists to lead the charge on research and prevention as most of us, including government programs that help subsidize access to basic dental care, are accustomed to paying for treatments.

Current research suggests that our dental health reflects the health of our entire bodies. We have begun to understand the link between what is happening in our mouths and our individual and cultural health, thanks to the groundbreaking work of Dr. Weston A. Price, anthropologist and dentist.

The impact of culture on teeth

Price practiced dentistry in Cleveland, Ohio in the early part of the 1900s. In an effort to understand tooth decay and physical degeneration, he studied teeth from different world cultures, specifically indigenous and isolated groups, including Inuit and North American indigenous groups, African tribal people, aboriginal peoples of New Zealand, Australia, South America, South Sea Island, Switzerland, and remote Gaelic communities. Price found decay-free, straight teeth and a healthy, structurally-sound, disease-resistant people. He came to believe the connection was largely based on diet as, across cultural groups, they tended to consume many times more calcium and other minerals, fat-soluble vitamins, and nutrient-rich animal foods than we are typically accustomed to today.

His work went beyond just showing that a mother’s diet during conception, pregnancy and lactation was essential to a child’s overall health, but that the father’s diet also mattered. He found that these same indigenous people, when converted to a more typical Western diet, were faced with many of the same issues he had seen in his Cleveland practice: crowded teeth, cavities, and gum disease.

The problem with amalgam tooth fillings

Price developed a series of principles meant to be guidelines to a happier, healthier mouth. Concepts like eating whole foods and taking a more conscious approach in dental health care can seem like no-brainers, however, this mindset is actually far outside of our current dental mainstream in North America. In fact, Dr. Schecter says that the standard in North American dentistry is to put amalgam (aka mercury) fillings into children. He says he doesn’t remember ever not putting a mercury filling into a child while in dentistry school. Mercury amalgams are the most common type of filling used, despite increasing evidence that a small amount of the mercury is released into the body where it can cause harm, especially to developing fetuses and children. The World Health Organization called for the phasing out of all amalgam fillings in 2011 warning that it releases a “significant amount of mercury” into the environment and that its use raises “general health concerns.” While Health Canada concludes that amalgam may not be advisable in pregnant women and children and the US FDA acknowledges the "developing neurological systems in fetuses and young children may be more sensitive to the neurotoxic effects of mercury vapor” neither government goes as far as to restrict its use even in these vulnerable populations.

Weston A. Price holistic dentistry guidelines

  • Eat nutrient-dense whole foods, properly grown and prepared.

  • Avoid root canals. If you have root canals that you suspect are causing disease, have them removed by a knowledgeable dentist.

  • Avoid mercury (amalgam) fillings. If you have amalgam fillings, have them removed by a holistic dentist who specializes in mercury filling replacement.

  • Orthodontics should include measures to widen the palate.

  • Extract teeth only when necessary, and then in such a way as to avoid leaving the jawbone with cavitation, which can be focal points of infection.

The great fluoride debate

Mercury isn’t the only toxin potentially weakening the health of our children. Toothpaste itself can also contain aluminum, Triclosan (an antibacterial pesticide) and SLS (a harsh detergent). The tricky part is that toothpastes are considered to have medicinal properties and thus, even in countries like Canada where labelling laws exist, manufacturers don’t have to reveal their ingredients. Further, many toothpastes on the market contain fluoride: possibly the most hotly debated topic in the care of teeth.

Although the real fluoride controversy is less about its presence in toothpaste and more about the fluoridation of public water supplies in many cities in the US and Canada, and the resulting ingestion by their citizens, there remains great debate over adding fluoride to toothpaste as a means of protecting teeth from cavities.   

As to whether or not a fluoride toothpaste is safe and medically necessary, especially in young children, there is research to suggest that fluoride, when considered as a topical treatment, does have a small cavity-preventing benefit. However, it’s important to note that if parents choose to use a fluoride toothpaste, there must be care exercised to ensure that children don’t overuse it or swallow it. If a parent chooses to forego it, they’re in good company: more and more biological or holistic dentists don’t routinely use fluoride in their practices at all.

According to Dr. Bruce Lanphear, professor with Simon Fraser University’s Faculty of Health Sciences and an investigator at BC Children’s Hospital, the research on fluoride’s safety and its efficacy has never been sufficient, and there is no real oral benefit shown from ingesting fluoride. He points out that it is not an essential nutrient, nor is it required for the proper functioning of the body. In fact, there is evidence that shows fluoride may interfere with healthy body functioning, particularly when it combines with toxins like aluminum and lead. Fluoride has been shown to slow down the time it takes for teeth to appear, which increases the risk of decay. Fluoride can also cause dental fluorosis, or tooth discolouration, which is estimated to affect 41% of American children.

Cavities are 95 to 100% preventable with dietary changes. ~ Dr. Roger Lucas DDS

tween girl wearing a pink toque and sunglasses with a cute smile
G-Stock Studio/

The link between diet and your teeth

There is a direct correlation between your diet and your dental health. In fact, “Cavities are 95 to 100% preventable with dietary changes,” according to Dr. Lucas. Yet, knowing this hardly equals a prescription for what is a healthy diet. I consider myself to have a great diet, I avoided toxins to the best of my ability in pregnancy, and I myself never had a cavity as a child. Yet, my child’s tooth rotted out just in time to reach the national average. 

I have long been a believer in the nutrient-rich diet, and especially its importance during the childbearing years and for young children. So, we have eaten lots of organic, grass-fed butter, bone broths, and vegetables. We also ferment foods to help create a great gut microbiome. And as much as possible I soak my beans and grains.

It is this latter bit that some would say is the missing piece for the healthy diets of those who still suffer from cavities. Most fresh foods like vegetables, grains and legumes, have some form of anti-nutrient that coat them and help protect the food in the field from their natural predators. Phytic acid is an anti-nutrient found in grains, nuts, seeds, and beans that can block the body’s ability to absorb calcium, zinc, magnesium, and iron: all minerals extremely important for teeth. There are ways to prepare foods so that the negative effects of the phytic acid are either entirely or partially minimized. As well, people with healthier gut microbiomes will be better able to digest the phytic acid than those who do not, and thus a healthy gut might mean this simply matters less. The key to reducing phytic acid in nuts, grains, and rice is to either sprout and cook them, or soak in water with some whey, lemon, or vinegar. Long soaks and many rinses are particularly important with beans.

Intuitively, this makes a lot of sense to me, as my daughter suffered from parasites before the problem occurred with her tooth. Perhaps a weak microbiome in combination with too many grains and beans improperly prepared was simply enough to take her over the edge to rotten teeth.

How certain foods add up to decay

In his book More Chocolate, No Cavities, Dr. Lucas says that for most people the diet aspect is even simpler than that. It really comes down to the fact that some foods, like those rich in protein and good fats and very low in starches and sugars, won’t cause cavities, while other foods will. He says that raw vegetable and pure chicken are never going to rot your teeth while fruit juice and crackers will start the process with a vengeance.

It’s not just whether the food will be turned into lactic acid and how fast, it’s also the “stickiness” of the food. That’s why crackers are worse than bread: crackers mixed with saliva, water or juice creates a plaster-like effect that causes crackers to stick badly to teeth, similar to sticky candy and dried fruits. 

He breaks down the path to keeping children cavity-free into a few simplified steps. The first is knowing which foods are okay. The second is remembering to swish with water after eating, avoiding sticky foods that can’t easily be swished away, and avoiding snacking on these bad-for-teeth foods.

Indeed, he says it’s really about math—that is, which foods add up to tooth decay more easily and how much time they spend on the teeth. Foods that can be converted to lactic acid (which are any foods with simple sugars such as starchy foods or sweets) will break down and then stick to the plaque on the teeth. There, this acid will immediately begin to eat away the enamel of the tooth unless brushed or vigorously swished away. This process can immediately be restored, and the tooth remineralized, once the acid is removed and saliva is presented. The saliva contains minerals that will begin to fill that microscopic hole.

There is the time the food spends on the teeth. Most foods will stay on your teeth long enough for the bad bacteria to start eating the sugar and carbs. The result is lactic acid that eats away at the tooth, which is mainly made up of calcium and phosphorous. If there was nothing on the teeth for the bad bacteria to eat, then the acid wouldn’t form and the tooth wouldn’t decay. Thus, if we can avoid eating foods with sugars or carbs or remove sugar or carbs immediately, the problem is reduced.

It is particularly essential to avoid sipping beverages or nibbling on foods all day long, most especially on sticky carbs, but even on relatively healthy, acidic foods like oranges. And, of course, while we can see why sipping a soda all day long would quickly cause decay to start happening, the same is true for juice, lattes, and that cup of sweetened tea that I have every morning (Dang!). It’s also true for health drinks like kombucha and smoothies. And it’s true for milk and formula.

How saliva supports dental health

Saliva is much more than a digestive element—it has the power to remineralize and rebuild teeth after the food debris is removed. Lactic acid stays on the teeth for about 20 minutes unless removed, and in that time it can demineralize and start to eat away at the teeth. The saliva, however, is the rebuilder, filling in these microscopic holes where the minerals get eroded by the acids. Saliva moving over and around your teeth starts to patch the minerals back into these microscopic holes. Tooth decay only starts to happen when this process gets out of balance, either because the decaying factors of the diet and exposure are too great for the saliva, or that the quantity or quality of the saliva is insufficient. Saliva production declines with age in most people. To create more saliva outside of eating you can benefit from practicing pooling saliva in the mouth and swishing it around your teeth and gums.

The impact of the microbiome on teeth

While quantity of saliva is one thing, quality also plays a role in how well some people can remineralize. This gets into the world of the mouth microbiome, which refers to the bacteria and other microbes that make up the environment of your mouth. Some people have healthier mouth microbiomes that are free-of or lower in Streptococcus mutans, which is believed to cause tooth decay.

The mouth is the beginning of the digestive tract, and the evidence that our digestion is intricately linked with our immune system is piling up fast. Stress can tip the microbiome of the mouth so that the bad bacteria are more in control. Remember that stress isn’t just an emotional issue, although that form can cause real physical damage. Stress also results from toxins, lack of solid sleep, and diets that are hard on our bodies. The key to having a healthy mouth microbiome, including a healthy mouth pH, a diversity of good bacteria, and plenty of bone and teeth enhancing vitamins and minerals, are a nutrient dense diet, good sleep, and minimal stress.

Foods that support a healthy gut microbiome will almost certainly support a healthy mouth microbiome: but they aren’t necessarily the same. The few studies that have been done on the benefits of good bacteria suggest their consumption – and by extension the consumption of all probiotic-rich foods such as yogurt, sauerkraut, and kimchi – can help reduce periodontal disease, bad breath, and perhaps even cavities. Yet studies also show that some lactobacillus strands, if left in the mouth (such as from chewing a child’s probiotic tablet), might contribute to cavity formation. It’s unclear, because the subject has been so little studied, whether some probiotics may be particularly helpful just in the mouth. Many holistic dentists suggest this is so and you can buy oral probiotics just for this purpose. Most of these also contain xylitol, which preliminary research shows may further help prevent cavities. The take-away is to take probiotic supplementation and eat probiotic-rich food, but don’t leave them on your teeth.

While dental health is clearly important as part of overall health, Dr. Schecter also says, “things happen.” In other words, “May cavities be your biggest health issue.”

10 ways to fight cavities

  1. Foods rich in healthy fats and proteins will support not only your overall health but also the health of your teeth. Beans and grains should be soaked overnight in whey mixed with water to help mitigate the effects of phytic acid.  

  2. Feed your child crunchy vegetables and clean protein for snacks and drink only water between meals. Starchy and sugary foods like crackers and breakfast cereals should be rare treats.

  3. Swish water after eating to help remove food particles and swish saliva around your mouth to help remineralize the teeth. Brushing twice a day is essential (for very young children you may not need to brush for the recommended full two minutes).

  4. Help build a healthier mouth microbiome. Adhere to the diet suggestions above and use toxin-free toothpaste and oral probiotics. 

  5. De-stress your mouth! Get sunshine, exercise, plenty of vitamin D, and avoid toxins.

  6. Consider oil pulling (which though unproven, some experts claim it can remove toxins from the body), or brush with oil occasionally, which can reduce plaque. Swish coconut oil or extra virgin olive oil around in your mouth, without swallowing, for 5-10 minutes. The longer you swish the oil, the more bacteria you will "pull" from your mouth.

  7. Start flossing kids' teeth as soon as teeth touch. But know that “there is no strong evidence that flossing prevents cavities,” according to Lucas. If you had to choose between flossing and having no crackers in the house, he’d choose the latter. He still recommends flossing because chances are your kid is going to eat crackers or pretzels if not at home.

  8. Make sure to stay well-hydrated. “Nobody drinks enough water,” says Dr. Schecter.

  9. Look for toothpaste that reveals its full ingredients list, is free of "no-nos", or is certified organic. Avoid SLS, Triclosan and aluminum. Or, you can make your own.
  10. Buy uncoated dental floss or ensure it’s made from natural materials such as silk. Many coated flosses use the same toxic substances used in nonstick pans.

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