Vitamin D: The “Calcium Manager” for Strong Teeth

Vitamin D: The “Calcium Manager” for Strong Teeth

If vitamin A is the architect of dental development, then vitamin D is the project manager that makes sure the construction materials – calcium and phosphorus – get delivered and installed in your child’s teeth. Vitamin D is famous for building strong bones, and teeth are no exception. In fact, a classic sign of vitamin D deficiency in childhood is rickets, a bone-softening disease, and its lesser-known dental counterpart: “rickety teeth” – teeth that are poorly mineralized and prone to decay.

Vitamin D: The Original Anti-Cavity Vitamin

Historically, vitamin D earned the nickname “the anti-caries vitamin” in some early dental research circles because numerous studies showed that improving children’s vitamin D status could significantly reduce cavities. As early as the 1920s and ’30s, dental researchers noticed that children who lived in sunny regions or spent a lot of time outdoors tended to have far fewer cavities than those who lived in sun-poor, industrial cities. Sunlight was giving those kids a healthy dose of vitamin D. Controlled trials around the world soon confirmed vitamin D’s power. In one notable study in England (1928), children who were given a vitamin D supplement developed up to 50% fewer new cavities than children who didn’t get the supplement – even though all groups ate a similar diet. Similar trials in the U.S., Canada, and Europe all echoed the same theme: vitamin D could consistently reduce the incidence of cavities by roughly one- third to one-half. These findings were so compelling that by the mid-20th century, public health campaigns began pushing cod liver oil for kids and even implementing “sunbathing” sessions at some schools in winter. Governments started fortifying foods like milk with vitamin D, aiming to improve children’s dental and bone health.

How does vitamin D fight cavities? Part of the answer is straightforward: it builds tougher teeth. A child replete with vitamin D will incorporate lots of calcium and phosphorus into their tooth enamel, making it dense like well-hardened cement. Such enamel is much more resistant to the acid produced by oral bacteria. Studies have found that kids with higher vitamin D levels tend to have thicker enamel and significantly lower rates of tooth decay. But there’s another layer: vitamin D also boosts the mouth’s immune defenses. It triggers the production of antimicrobial peptides – essentially natural antibiotics – in the saliva and oral tissues. One of these is called cathelicidin, which can inhibit common cavity-causing bacteria. So vitamin D defends teeth in two ways: strengthening the tooth’s structure and enhancing the mouth’s resistance to germs.

Without enough vitamin D, the scales tip in favor of cavities. Teeth erupt with less mineralization and may even emerge later than normal (vitamin D deficiency has been linked to delayed teething in infants). Thin enamel means that as soon as oral bacteria produce acid (for instance, when the child eats carbohydrates), the acid can dissolve the mineral more easily, creating a cavity. And a lack of vitamin D could leave the oral immune system underpowered, giving harmful bacteria an easier time establishing damaging biofilms (plaque). This is why, in the era before modern dentistry, some of the most effective “treatments” for chronic tooth decay were dietary. For example, during the 1930s, some orphanages and hospitals found they could virtually stop rampant cavities in children simply by giving them daily high-quality, unprocessed, cod liver oil (rich in vitamins D and A) and improving their diet. Even existing cavities often slowed or halted. These nutritional interventions were quietly very successful, though they’ve been largely forgotten in the age of fillings and fluoride.

Natural Food Sources of Vitamin D

Humans can manufacture vitamin D from sun exposure, which is ideal, but in practice many children (and adults) today don’t get enough sunlight to maintain optimal vitamin D levels – especially if they live in northern climates or spend most of their time indoors or covered in sunscreen. That’s where diet becomes crucial. The natural food sources of vitamin D are relatively few (and all animal-derived). The most potent by far is high-quality, unprocessed cod liver oil, which for good reason was a staple “vitamin D supplement” for generations. Just a teaspoon of high-quality cod liver oil can provide a substantial dose of vitamin D along with vitamin A. Other excellent sources are fatty fish such as salmon, sardines, mackerel, and herring. A serving of wild salmon, for instance, is not only rich in omega-3s but also can cover a good portion of a child’s vitamin D needs. Fish eggs (roe) and shellfish like shrimp also contain some vitamin D. Egg yolks contribute a bit of vitamin D (with higher amounts if the hens roam outdoors under the sun). Dairy products like butter and cheese from grass-fed animals can have small amounts, but not usually enough alone. One lesser-known source: the fat of animals that get sunshine. For example, traditional lard from animals raised outdoors contains vitamin D stored in the fat.

To ensure your family is getting enough vitamin D, a combination of moderate sun exposure and vitamin-D-rich foods is the ancestral approach. Let the kids play outside when the sun is strong and include vitamin D–laden foods regularly in meals. In winter or for kids who can’t eat fish, using high-quality, unprocessed cod liver oil. It’s worth noting that vitamin D works hand-in- hand with vitamins A and K2 – those nutrients help direct where calcium goes and how it’s used. That’s why focusing on a range of fat-soluble vitamins together is ideal (more on that synergy soon). But even on its own, vitamin D is a powerhouse for preventing cavities and supporting a child’s overall oral health.

At KareFor, we recognize how essential vitamin D is – and how difficult it can be for modern families to get enough through diet alone. Our supplement formulations include natural sources of vitamin D, helping ensure kids get their “sunshine vitamin” even on cloudy days.