You brush twice daily and still get cavities. Your genes may be why.

Your VDR gene codes for the receptor that lets vitamin D actually work in your cells. Without a functioning VDR, vitamin D circulates in your bloodstream but can’t activate the antimicrobial peptides and immune responses your mouth needs to fight off decay-causing bacteria.

Several VDR variants, including the most common FokI polymorphism, reduce the receptor’s efficiency. Roughly 40-50% of the population carries at least one variant that makes their VDR less responsive to vitamin D signaling. This means vitamin D deficiency can’t be fixed by taking more vitamin D if your VDR isn’t working properly; you need the receptor to function first.

If you have a VDR variant, your mouth has a harder time mounting an antimicrobial response. Bacteria colonize more easily, inflammation rises, and decay accelerates. You may notice that you’re sensitive to vitamin D levels that don’t seem to matter for other people, or that supplementing vitamin D alone doesn’t improve your gum health.

Your gums are made largely of type I collagen, the same structural protein that holds skin, tendons, and bone together. COL1A1 is the gene that codes for the instructions to make this collagen. When your gums are healthy, collagen fibers anchor teeth to bone and resist bacterial invasion. When collagen is weak, your gums recede, periodontal pockets deepen, and bone loss accelerates.

COL1A1 variants that reduce collagen cross-linking or structural stability affect roughly 20-30% of the population. People with these variants often have thinner, less resilient gum tissue that breaks down faster even with good oral hygiene. The problem isn’t inflammation or bacteria primarily; it’s that the structural foundation is weaker.

You may notice that your gums bleed easily, recede despite excellent brushing, or don’t heal well after dental procedures. Your dentist might comment that your gum tissue seems thin or fragile. This is often genetic, not a sign of poor care.

MTHFR is the enzyme that converts folate from food into the active methylfolate your cells use to build DNA, repair tissue, and mount immune responses. Your mouth has one of the highest cell-turnover rates in your body. Healthy gum tissue, mucosal healing, and immune cell production all depend on MTHFR working well.

The MTHFR C677T variant, present in approximately 35-45% of the population, reduces enzyme efficiency by 35-70%. The A1298C variant affects another 30-40% of people, with less dramatic impact. If you have either variant, your cells are struggling to convert dietary folate into the methylfolate they need for immune function and tissue repair. You can eat a diet rich in leafy greens and still be functionally folate-depleted at the cellular level.

You may notice slow healing after dental work, persistent low-grade gum inflammation, or susceptibility to mouth sores. Your immune system can’t mount an effective response because it simply doesn’t have the cofactors it needs.

IL6 is the cytokine that signals your immune system to ramp up inflammation in response to threat. In your gums, a little inflammation is protective, telling immune cells to patrol and defend. But if IL6 is overactive, inflammation becomes chronic, bone-destroying, and impossible to control through oral hygiene alone.

Common IL6 variants, particularly the rs1800795 -174G>C polymorphism, affect roughly 30-40% of the population and increase baseline IL-6 production. People with these variants tend to have persistently elevated IL-6 in their gingival fluid, driving a chronic inflammatory state that makes gum disease and bone loss more aggressive. Your immune system is not fighting an infection; it’s stuck in an inflammatory loop.

You may experience gum swelling that comes and goes, bleeding that doesn’t improve with better oral care, or rapid bone loss despite meticulous brushing. Your gums feel tender or sore even when your hygiene is excellent. Inflammation is happening at a baseline level regardless of bacterial load.

IL1B codes for interleukin-1 beta, one of the first and most potent inflammatory signals your immune system releases. In the gums, IL-1B tells bone-resorbing cells to activate and destroy tissue. This is appropriate when fighting a real infection, but IL1B overactivity drives periodontal disease progression independent of how much bacteria is actually present.

The IL1B +3954 variant, carried by roughly 35-40% of the population, significantly increases IL-1B production in gingival fluid. People with this variant often have severe periodontitis and rapid bone loss even when bacterial counts are similar to people without the variant. The problem isn’t bacterial; it’s an overactive inflammatory response.

You may notice that your gum disease seems disproportionate to your bacterial load or hygiene habits, that your dentist comments on rapid bone loss for someone your age, or that your gums bleed heavily during cleanings. The tissue destruction is happening because your immune system is amplifying the inflammatory response.

MMP1 codes for an enzyme that breaks down collagen and other proteins in your gum tissue and the periodontal ligament holding your teeth in place. A little MMP1 activity is normal and necessary for tissue remodeling. But if MMP1 is overactive, it degrades connective tissue faster than your body can rebuild it.

MMP1 variants that increase enzyme production and activity affect roughly 25-35% of the population. People with high-activity MMP1 variants often experience accelerated tissue breakdown, periodontal pocket formation, and gum recession despite adequate immune function and reasonable oral hygiene. Your gums are literally dissolving faster than they can repair.

You may notice gum recession that progresses despite excellent brushing, tooth mobility that develops early, or a feeling that your teeth are becoming loose for no clear reason. Your dentist might comment on rapid periodontal decline. The bone and connective tissue are breaking down because your MMP1 is overactive.