Poor nutrition may cause oral health problems, whilst oral health problems can also affect nutritional and health status. A healthy jaw, teeth, gums and muscles are necessary to support digestion, which starts with chewing foods thoroughly. When oral health becomes compromised, food intake and nutritional status may be negatively affected. In other situations, such as with advanced periodontitis, bacteria present in inflamed gums can enter the bloodstream and may cause inflammation, raising the risk of cardiovascular disease, diabetes and inflammatory conditions such as rheumatoid arthritis. It's therefore vital to ensure oral hygiene throughout our lifetime. In this article we consider the role nutrition plays and provide an outline to support different oral health complaints.

A lack of calcium in the diet can cause the body to extract calcium from the bones and teeth which, overtime, may lead to jawbone thinning, loosening of teeth and osteoporosis. Vitamin D is required to support both calcium absorption from the diet and bone mineralisation. A lack of vitamin D can therefore affect the calcification and strength of teeth. Vitamin K2 supports the body in transporting calcium from the saliva to bones and teeth, with the help of vitamin D. A lack of these important nutrients can leave teeth susceptible to tooth decay.

Almost half of all adults in the western world have some degree of periodontitis. Periodontitis, or periodontal disease, refers to infection involving the gums, jawbone and connective tissues between the teeth and gums. It begins with inflamed gums and, in severe cases, can cause teeth to become loose or even fall out. 

There is a strong link between periodontal disease and diets low in polyunsaturated fats (omega-3), vitamins A, B, C, K2, calcium and polyphenols. (1) Vitamin A is important for maintaining healthy mucous membranes, including those in the mouth. B-vitamins, especially folate, improve resistance to bacterial infections whilst an increase in serum vitamin B12 levels has been shown to decrease signs of periodontitis. An important antioxidant, vitamin C has the ability to strengthen periodontal ligaments. Research has shown that those with the highest vitamin C intake and blood levels experience significantly less periodontitis than those with the lowest. (2) Vitamin K2 slows the progression of periodontal disease by reducing inflammation and calcification of the periodontal ligament and scarring of the gums. (3) Vitamin D plays a protective role by decreasing inflammation and improving bone mineralisation. (4)

Interestingly, the tongue is often used as a diagnostic tool in Traditional Chinese Medicine with many changes suggesting a nutritional imbalance. For example, iron deficiency can manifest as a swollen tongue (evident by ridges along the side), that may also be pale, smooth and shiny. B-vitamin deficiency may cause tongue inflammation, with severe B12 deficiency resulting in a bright red, smooth, shiny and sensitive tongue. A smooth and shiny tongue may also indicate a protein or zinc deficiency, low calorie diet or coeliac disease, whilst a painful, white-coated tongue, a smooth pink patch on the tongue or sore white or red patches on the inside of the cheeks may indicate oral thrush.

Angular cheilitis, the painful cracks that occasionally develop in the corners on the outside of the lips, is linked with a lack of B-vitamins, iron or zinc in the diet, all of which may contribute to skin breakdown.

Small white sores, known as aphthous ulcers or canker sores, can develop due to a lack of zinc, iron, folate or vitamin B12, amongst other factors.

Vitamin D deficiency is common in the UK, particularly among those who do not get much sun exposure. Supplementation is recommended between the months of October and March to maintain vitamin D status but may be beneficial year-round.

For dental health, vitamin K2 in the MK-7 form is most beneficial due to its ability to increase bone calcification & prevent calcification of blood vessels and soft tissue. (5) Vitamin K2 MK-7 is difficult to obtain in decent amounts in the diet, the only good source is natto, a fermented soya curd, with smaller amounts found in other fermented products. Some blame increasing tooth decay in the modern era on a lack of these vitamin K2-providing foods. (6)

Calcium is found in dairy, eggs, fish, leafy vegetables, seeds and nuts, whilst vitamin-C rich foods include oranges bell peppers, broccoli and tomatoes.

Not only are nutrients important for maintaining oral health, other dietary factors can also play a role. A high intake of sugar can be a risk factor for tooth decay whilst a diet high in sugar and saturated fat has been linked to periodontal disease. A high consumption of acidic foods and drinks can be a cause of sensitive teeth. Those who experience canker sores may develop them after consumption of spicy, acidic or salty foods. Tooth discolouration can be caused by certain foods and drinks, including coffee, tea, coke and wine. White patches on the teeth may suggest excess fluoride intake.

Where necessary, consider reducing your intake of aggravating foods and drinks and limiting sources of fluoride by switching to a non-fluoride toothpaste and using a filter for your tap water.

Poor dental hygiene can cause plaque to accumulate on the gums, leading to inflammation (gingivitis). This can signal the first stage of periodontitis. Poor dental hygiene is also a factor in tooth discolouration as bacteria can build-up and lead to tartar, which often presents with a grey hue. A good dental routine is therefore important for maintaining oral health. However, beware of brushing teeth too forcefully as this may cause gum recession, bleeding gums and the wearing down of dental enamel, a causative factor for sensitive teeth. Areas of recession are more prone to bacterial growth, so it’s important to maintain a careful brushing and flossing regimen.

Smoking can also affect gum health and is implicated in gum recession and tooth discolouration.

Saliva has many roles in the body, not only does it support the digestion of foods, it forms a neutral buffering fluid to counteract acid and minimise the de-mineralisation of enamel. Support saliva production by making time for your meals and focusing on the smells and flavours of your food.

Stress also affects oral health and can be a causative factor for cold sores and canker sores. If you experience these regularly, consider stress management techniques including yoga, gentle walks and meditation.

Try brushing teeth with baking soda a few times per week - it’s mildly abrasive, disrupts bacterial biofilms and raises the oral pH, creating unfavourable conditions for acid-loving bacteria. With its antioxidant and antimicrobial properties, try using strong green tea as a mouthwash. It helps to raise the pH of the mouth and has been shown to be equal to chlorhexidine mouthwash at managing gum inflammation and plaque, without any side effects. (8)

Whilst we hope this article has highlighted the many ways good nutrition can support oral health, there are various factors beyond the scope of nutrition that can play a role. Medication may cause tooth discolouration and tooth decay, whilst some health conditions may also affect oral health. Should you have any ongoing concerns regarding your oral health, speak to your dentist who may refer you to your GP.

1. Martinon, P et al., Nutrition as a Key Modifiable Factor for Periodontitis and Main Chronic Diseases. J Clin Med. 2021;10(2):197. Published 2021 Jan 7. doi:10.3390/jcm10020197
2. Tada A, Miura H. The Relationship between Vitamin C and Periodontal Diseases: A Systematic Review. Int J Environ Res Public Health. 2019;16(14):2472. Published 2019 Jul 11. doi:10.3390/ijerph16142472
3. Shea MK, Booth SL, Massaro JM, et al. Vitamin K and vitamin D status: associations with inflammatory markers in the Framingham Offspring Study. Am J Epidemiol. 2008;167(3):313-320. doi:10.1093/aje/kwm306
4. Botelho J, Machado V, Proença L, Delgado AS, Mendes JJ. Vitamin D Deficiency and Oral Health: A Comprehensive Review. Nutrients. 2020 May 19;12(5):1471. doi: 10.3390/nu12051471
5. Schurgers, L et al., Vitamin K–containing dietary supplements: comparison of synthetic vitamin K1 and natto-derived menaquinone-7, Blood, Volume 109, Issue 8, 2007, Pages 3279-3283, ISSN 0006-4971,https://doi.org/10.1182/blood-2006-08-040709
6. Southward K. A hypothetical role for vitamin K2 in the endocrine and exocrine aspects of dental caries. Med Hypotheses. 2015 Mar;84(3):276-80. doi: 10.1016/j.mehy.2015.01.011. Epub 2015 Jan 19. PMID: 25636605
7. Pizzorno, J.,The Clinician's Handbook of Natural Medicine (Third Edition), 2016 Chapter 34 Pages 375-380, https://doi.org/10.1016/B978-0-7020-5514-0.00043-9
8. Mathur A, Gopalakrishnan D, Mehta V, Rizwan SA, Shetiya SH, Bagwe S. Efficacy of green tea-based mouthwashes on dental plaque and gingival inflammation: A systematic review and meta-analysis. Indian J Dent Res. 2018 Mar-Apr;29(2):225-232. doi: 10.4103/ijdr.IJDR_493_17. PMID: 29652019