When’s the last time your dentist asked about your blood sugar?
Probably never.
But here’s what I’ve learned in 40+ years of practice: If your blood sugar is high, it can interfere with normal gum repair.
You could floss three times a day, use the “right” toothpaste, and never miss a cleaning.
And your gums will still bleed. Because what happens in your mouth happens in the rest of the body, too.
High blood sugar harms gums in four ways:
- Feeds bad bacteria – They thrive on glucose
- Slows healing – Your tissue can’t repair itself
- Weakens immunity – Infections stick around longer
- Cranks up inflammation – Throughout your entire body
And it goes both ways…
Gum disease makes blood sugar harder to control. The chronic inflammation from infected gums worsens insulin resistance throughout your body.
98 million Americans have prediabetes. 80% don’t know it.
For many people, their blood sugar is elevated but not high enough to be diagnosed as diabetic.
But high enough to quietly wreck their gums.
If this sounds like you, blood sugar might be the culprit:
✓ Gums bleed no matter how gently you brush
✓ Bad breath that won’t quit despite perfect hygiene
✓ Gum infections that keep coming back
✓ Slow healing after dental work
✓ Dry mouth at night
✓ More cavities lately—even though nothing’s changed
Your dentist keeps telling you to “brush better.” You’re doing everything right.
But you can’t out-brush a blood sugar problem.
What I’m Doing to Protect My Gums
1. I track my metabolic markers annually. I like to see my fasting insulin under 5 μIU/mL (ideally under 3), fasting glucose under 100 mg/dL, and A1C under 5.7%. These are the numbers I personally aim for.
2. I take berberine. Just because I have low fasting insulin doesn’t mean I live in a low-insulin world. That number only reflects your overnight baseline. It doesn’t capture what happens when you eat—especially when you eat out.
Even metabolically healthy people face constant insulin signaling from: Restaurant food, refined starches disguised as “whole grain,” stress hormones…
Berberine supports healthy blood sugar and energy metabolism at the cellular level. I think of it as metabolic insurance.
There’s also a gut angle most people miss: Berberine has poor systemic absorption, which sounds like a downside but isn’t. It stays in your gut, where it:
– Supports beneficial bacteria
– Promotes short-chain fatty acid production
– Helps maintain a balanced inflammatory response
All of which matter for your gums! The research dose is 500mg twice daily with meals. This is the one I take, but keep in mind berberine can interact with diabetes medications—talk to your doctor first if you’re on prescriptions.
3. I support my oral microbiome. Use prebiotic toothpaste (this one) to feed good bacteria and make sure to never skip flossing—sorry, boring recommendation, I know, but if you struggle to floss, I highly recommend a flossing stick like this affordable one or this pricier one).
Skip antiseptic mouthwashes—they kill the beneficial bacteria you need—and oil pull instead (link to my all-time favorite oil pulling blend formulated to support gum health and the oral microbiome).
Chew xylitol gum after meals to balance pH and stimulate saliva.
Eat prebiotic foods: garlic, onions, leeks, asparagus, chicory root—they feed beneficial gut bacteria that produce short-chain fatty acids. And fermented foods like kimchi and sauerkraut help maintain microbial diversity. Both support the kind of balanced inflammatory response that keeps gums healthy.
4. I recommend working with dentists who understand the mouth-body connection. In dental school, we’re taught to focus on teeth in isolation, but in my private practice, I learned to look at the whole patient. That’s why I created a Functional Dentist Directory on my website. If you’re a dentist or myofunctional therapist who thinks “whole body” and “root cause” I invite you to join us!
Mark
Further Reading and Citations
Blood Sugar and Periodontal Disease
Zhao M, Xie Y, Gao W, Li C, Ye Q, Li Y. Diabetes mellitus promotes susceptibility to periodontitis—novel insight into the molecular mechanisms. Front Endocrinol. 2023;14:1192625. https://doi.org/10.3389/fendo.2023.1192625
Yang S, Li Y, Liu C, Wu Y, Wan Z, Shen D. Pathogenesis and treatment of wound healing in patients with diabetes after tooth extraction. Front Endocrinol. 2022;13:949535. https://doi.org/10.3389/fendo.2022.949535
Simpson TC, Clarkson JE, Worthington HV, MacDonald L, Boyers D, Hulks G, et al. Treatment of periodontitis for glycaemic control in people with diabetes mellitus. Cochrane Database Syst Rev. 2022;4:CD004714. https://doi.org/10.1002/14651858.CD004714.pub4
Hajishengallis G, Chavakis T. Local and systemic mechanisms linking periodontal disease and inflammatory comorbidities. Nat Rev Immunol. 2021;21:426-440. PMID: 33510490
Dommisch H, Kuzmanova D, Jönsson D, Grant M, Chapple I. Effect of micronutrient malnutrition on periodontal disease and periodontal therapy. Periodontol 2000. 2018;78(1):129-153. PMID: 30198135
Management of periodontal disease in patients with diabetes—good clinical practice guidelines: A joint statement by Indian Society of Periodontology and Research Society for the Study of Diabetes in India. J Indian Soc Periodontol. 2020;24(6):498-525. PMID: 33487831
Berberine Efficacy
Yin J, Xing H, Ye J. Efficacy of berberine in patients with type 2 diabetes mellitus. Metabolism. 2008;57(5):712-717. PMID: 18442638
Li C, He J, Wang W, Li N, Zheng X, Liu Y, et al. Glucose-lowering effect of berberine on type 2 diabetes: A systematic review and meta-analysis. Front Pharmacol. 2022;13:1015045. https://doi.org/10.3389/fphar.2022.1015045
Guo Y, Chen Y, Tan ZR, Klaassen CD, Zhou HH. The effect of berberine on metabolic profiles in type 2 diabetic patients: A systematic review and meta-analysis of randomized controlled trials. Oxid Med Cell Longev.
2021;2021:2074610. https://doi.org/10.1155/2021/2074610
Liang Y, Xu X, Yin M, Zhang Y, Huang L, Chen R, et al. Metformin and berberine, two versatile drugs in treatment of common metabolic diseases. Oncotarget. 2018;9(11):10135-10146. PMID: 29515773
Dong H, Wang N, Zhao L, Lu F. Berberine in the treatment of type 2 diabetes mellitus: a systemic review and meta-analysis. Evid Based Complement Alternat Med. 2012;2012:591654. PMID: 23118793
Periodontal Disease and Cognitive Decline
Fu YD, Li CL, Hu CL, Pei MD, Cai WY, Li YQ, et al. Meta analysis of the correlation between periodontal health and cognitive impairment in the older population. J Prev Alzheimers Dis. 2024;11(5):1307-1315. PMID: 39350376
Asher S, Stephen R, Mäntylä P, Suominen AL, Solomon A. Periodontal health, cognitive decline, and dementia: A systematic review and meta-analysis of longitudinal studies. J Am Geriatr Soc. 2022;70(9):2695-2709. PMID: 36073186
Guo H, Chang S, Pi X, Hua F, Jiang H, Liu C, et al. The effect of periodontitis on dementia and cognitive impairment: a meta-analysis. Int J Environ Res Public Health. 2021;18(13):6823. PMID: 34202071
Periodontal Disease and Cardiovascular Disease
Janket SJ, Baird AE, Chuang SK, Jones JA. Meta-analysis of periodontal disease and risk of coronary heart disease and stroke. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2003;95(5):559-569. PMID: 12738947
Larvin H, Kang J, Aggarwal VR, Pavitt S, Wu J. Risk of incident cardiovascular disease in people with periodontal disease: a systematic review and meta-analysis. Clin Exp Dent Res. 2021;7(1):109-122. PMID: 32926572
Periodontal Disease and Atherosclerotic Cardiovascular Disease: A Scientific Statement From the American Heart Association. Circulation. 2025;151(3):e93-e115. https://doi.org/10.1161/CIR.0000000000001390
Prediabetes Statistics
Centers for Disease Control and Prevention. National Diabetes Statistics Report. 2024. https://www.cdc.gov/diabetes/php/data-research/index.html
Centers for Disease Control and Prevention. Prediabetes—Your Chance to Prevent Type 2 Diabetes. Updated 2024. https://www.cdc.gov/diabetes/about/prediabetes.html
American Diabetes Association. Standards of Care in Diabetes—2025. Diabetes Care. 2025;48(Suppl 1):S1-S321.