What Causes Tooth Decay?
To better understand how diet influences tooth decay, it is important to understand what causes tooth decay.1 Harmful bacteria in the mouth can grow and multiply in plaque that forms around teeth. These bacteria metabolize sugar, creating acids that demineralize enamel and dentin. Demineralization — a loss of calcium — weakens teeth, leading to dental caries, cavities, increased bacteria, and eventually tooth loss. In addition to diet, conditions that impair the normal growth and development of teeth can significantly increase the risk of tooth decay.2
Nutritional Deficiencies and Tooth Decay
Proper nutrition requires getting enough vitamins and minerals in your diet as well as a healthy balance of other nutrients. Poor nutrition can cause or contribute to tooth decay at any point in a person’s life. Malnourishment in the womb and during childhood can impair the normal development of the teeth and oral cavity. Even before teeth first erupt, insufficient dietary intake of vitamin A, vitamin D, and protein can impair enamel growth.2 Calcium and vitamin D deficiencies can prevent proper mineralization of teeth, increasing the risk of tooth decay.3 A poor diet can also affect normal saliva production, which is needed to help protect against tooth decay. Deficiencies of vitamin A, protein, zinc, and iron can impair normal saliva production.2
Sugar and Tooth Decay
When it comes to diet and tooth decay, sugar consumption may be the single most important factor for causing or preventing tooth decay. Natural sugars found in fruits, vegetables, and milk products tend to protect against tooth decay.4 However, foods containing added sugars, especially refined sugar, directly contribute to the loss of tooth enamel and dentin.4 This includes beverages such as sodas and fruit juices as well as sweetened foods and, of course, candy and other sweets.
Starch, like sugar, is a carbohydrate. Starchy foods such as pasta, potatoes, bread, and grains do not contribute as much to tooth decay as sugar, but they can still increase the risk of decay, especially when added sugars are also present.2
Added sugars and dental caries
Eating foods with added sugars increases the risk of dental caries. Both the amount of sugar consumed and the frequency with which sugar is consumed can influence the severity of tooth decay.4 Any amount of added sugar in the diet can increase the risk of tooth decay, but that risk is further increased by eating or drinking large amounts of sugar at one time or eating smaller amounts of sugar more frequently. The stickiness of sugary foods also affects tooth decay risk. Foods that adhere to the teeth, such as chewy candy, increase the risk of dental caries.
Dietary Changes To Prevent Tooth Decay
A healthy, balanced diet should include a variety of fruits, vegetables, whole grains, and protein that can provide your body with the vitamins, minerals, and other nutrients that it needs. Healthy eating is essential to overall health as well as oral health. This requires avoiding foods that promote tooth decay.
Eating habits and tooth decay
What you eat affects your oral health, but how you eat also plays a role. Avoid sugary food and drinks before bedtime. For young children, it is important to avoid giving them a bottle when they go to sleep, as this can lead to dental caries.
Avoid acidic foods
Food and beverages that are acidic can erode tooth enamel, which contributes to tooth decay.5 This includes soda, citrus juices, apple juice, powdered drinks, and many flavored beverages, including sparkling water and some teas. Rinsing your mouth, drinking milk, or eating cheese can reduce the negative effect of acidic food and drinks.
Replace sugar with other sweeteners
Avoid foods sweetened with sugar, honey, or syrups (corn syrup, maple syrup, sorghum syrup, and cane sugar molasses), as these all can contribute to tooth decay and other conditions such as diabetes and obesity.6 Low-calorie natural sweeteners like stevia and monk fruit do not contribute to tooth decay.4 Artificial sweeteners (saccharin, sucralose, aspartame, and acesulfame potassium) and sugar alcohols (xylitol, sorbitol) are not metabolized by bacteria and do not contribute to tooth decay. Research shows that the sugar alcohol xylitol, commonly used in sugar-free gum and candy, can actually help prevent tooth decay.7
Eat foods that help prevent tooth decay
Many healthy foods can lower your risk of tooth decay. Foods high in fiber can help reduce the effect of dietary sugar on the teeth.4 Cheese, milk, and other dairy products can provide calcium and vitamin D to strengthen teeth and bones. Whole grains, peanuts, hard cheeses, and sugar-free chewing gum can all stimulate saliva production that helps protect against dental caries.4
Make Healthier Choices
There is more to preventing tooth decay than just brushing and flossing your teeth. Good oral hygiene is essential to good oral health, but what you eat also plays a significant role in either causing or preventing tooth decay. It is important to understand how what we eat and drink affects our oral health as well as our overall health. However, knowing is only half the struggle; you have to put this knowledge to use and make healthier choices.
- National Institute of Dental and Craniofacial Research. Tooth Decay. Accessed March 9, 2023. https://www.nidcr.nih.gov/health-info/tooth-decay
- Moynihan P, Petersen PE. Diet, nutrition and the prevention of dental diseases. Public Health Nutr. 2004 Feb;7(1A):201-226. doi: 10.1079/phn2003589. PMID: 14972061
- Scardina GA, Messina P. Good oral health and diet. J Biomed Biotechnol. 2012;2012:720692. doi: 10.1155/2012/720692. Epub 2012 Jan 26. PMID: 22363174; PMCID: PMC3272860
- Tungare S, Paranjpe AG. Diet and Nutrition To Prevent Dental Problems. [Updated 2022 Sep 9]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Accessed March 9, 2023. Available from: https://www.ncbi.nlm.nih.gov/books/NBK534248/
- MouthHealthy. Erosion: What You Eat and Drink Can Impact Teeth. Accessed March 9, 2023. https://www.mouthhealthy.org/all-topics-a-z/dietary-acids-and-your-teeth/
- Arshad S, Rehman T, Saif S, et al. Replacement of refined sugar by natural sweeteners: Focus on potential health benefits. Heliyon. 2022 Sep 20;8(9):e10711. doi: 10.1016/j.heliyon.2022.e10711. PMID: 36185143; PMCID: PMC9519493
- Janakiram C, Deepan Kumar CV, Joseph J. Xylitol in preventing dental caries: A systematic review and meta-analyses. J Nat Sci Biol Med. 2017 Jan-Jun;8(1):16-21. doi: 10.4103/0976-9668.198344. PMID: 28250669; PMCID: PMC5320817