Oral Health | The Nutrition Source | Harvard T.H. Chan School of Public Health – HSPH News
“There is no health without oral health.” You may have heard this statement but what does it mean? The health of our mouth, or oral health, is more important than many of us may realize. It is a key indicator of overall health, which is essential to our well-being and quality of life.
Although preventable to a great extent, untreated tooth decay (or cavities) is the most common health condition worldwide. When we think about the potential consequences of untreated oral diseases including pain, reduced quality of life, lost school days, disruption to family life, and decreased work productivity, making sure our mouths stay healthy is incredibly important. 
The mouth, also called the oral cavity, starts at the lips and ends at the throat. A healthy mouth and well-functioning teeth are important at all stages of life since they support human functions like breathing, speaking, and eating. In a healthy mouth, tissues are moist, odor-free, and pain-free. When we talk about a healthy mouth, we are not just talking about the teeth but also the gingival tissue (or gums) and the supporting bone, known together as the periodontium. The gingiva may vary in color from coral pink to heavily pigmented and vary in pattern and color between different people. Healthy gingiva is firm, not red or swollen, and does not bleed when brushed or flossed. A healthy mouth has no untreated tooth decay and no evidence of lumps, ulcers, or unusual color on or under the tongue, cheeks, or gums. Teeth should not be wiggly but firmly attached to the gingiva and bone. It should not hurt to chew or brush your teeth.
Throughout life, teeth and oral tissues are exposed to many environmental factors that may lead to disease and/or tooth loss. The most common oral diseases are tooth decay and periodontal disease. Good oral hygiene and regular visits to the dentist, combined with a healthy lifestyle and avoiding risks like excess sugar and smoking, help to avoid these two diseases.
Just like a healthy body, a healthy smile depends on good nutrition. A balanced diet with adequate nutrients is essential for a healthy mouth and in turn, a healthy mouth supports nutritional well-being. Food choices and eating habits are important in preventing tooth decay and gingival disease.
Minerals like calcium and phosphorus contribute to dental health by protecting and rebuilding tooth enamel.  Enamel is the hard outer protective layer of the tooth (fun fact: enamel is the hardest substance in the human body). Eating foods high in calcium and other nutrients such as cheese, milk, plain yogurt, calcium-fortified tofu, leafy greens, and almonds may help tooth health.  While protein-rich foods like meat, poultry, fish, milk and eggs are great sources of phosphorus.
When it comes to a healthy smile, fruits and vegetables are also good choices since they are high in water and fiber, which balance the sugars they hold and help to clean the teeth.  These foods also help stimulate saliva, which helps to wash away acids and food from teeth, both neutralizing acid and protecting teeth from decay. Many fruits and vegetables also have vitamins like vitamin C, which is important for healthy gingiva and healing, and vitamin A, another key nutrient in building tooth enamel.
Water is the clear winner as the best drink for your teeth—particularly fluoridated water. It helps keep your mouth clean and helps fight dry mouth. Fluoride is needed regularly throughout life to protect teeth against tooth decay.  Drinking water with fluoride is one of the easiest and most beneficial things you can do to help prevent cavities.
Nutrition and oral health are closely related. The World Health Organization defines malnutrition as deficiencies, excesses, or imbalances in a person’s intake of energy and/or nutrients. This means that malnutrition can be over-nutrition or undernutrition. Dental pain or missing teeth can lead to difficulty chewing or swallowing food which negatively affects nutrition. This may mean eating fewer meals or meals with lower nutritional value due to impaired oral health and increased risk of malnutrition. On the other hand, lack of proper nutrients can also negatively affect the development of the oral cavity, the progression of oral diseases and result in poor healing.  In this way, nutrition affects oral health, and oral health affects nutrition.
Nutrition is a major factor in infection and inflammation.  Inflammation is part of the body’s process of fighting against things that harm it, like infections and injuries. Although inflammation is a natural part of the body’s immune response to protect and heal the body, it can be harmful if it becomes unbalanced. In this way inflammation is a dominant factor in many chronic diseases. Periodontal diseases and obesity are risk factors involved in the onset and progression of chronic inflammation and its consequences. 
While it may appear that oral diseases only affect the mouth, their consequences can affect the rest of the body as well. There is a proven relationship between oral and general health. Many health conditions may increase the risk of oral diseases, and poor oral health can negatively affect many general health conditions and the management of those conditions. Most oral diseases share common risk factors with chronic diseases like cardiovascular disease, cancers, diabetes, and respiratory diseases. These risk factors include unhealthy diets, particularly those high in added sugar, as well as tobacco and alcohol use. 
Infective endocarditis (IE), an infection of the inner lining of the heart muscle, can be caused by bacteria that live on teeth.  Gingivitis and periodontitis are inflammatory diseases of the gingiva and supporting structures of the teeth caused by specific bacteria. There is evidence that the surface of inflamed tissue around teeth is the point of entry for the specific bacteria that cause as much as 50% of the IE cases in the U.S. annually. This means that improving oral hygiene may help in reducing the risk of developing IE. In addition, periodontal disease may be associated with heart disease and shares risk factors including tobacco use, poorly controlled diabetes, and stress. [9,10]
Oral health is an important part of prenatal care. Poor oral health during pregnancy can result in poor health outcomes for both mother and baby. For example, studies suggest that pregnant women who have periodontal disease may be more likely to have a baby that is born too early and too small.  Hormonal changes during pregnancy, particularly elevated levels of progesterone, increase susceptibility to periodontal disease, which includes gingivitis and periodontitis. For this reason, your dentist may recommend more frequent professional cleanings during your pregnancy.
If you are struggling with morning sickness, the stomach acid from vomiting can erode or wear away tooth enamel. To help prevent the effects of erosion, rinse your mouth with 1 teaspoon of baking soda mixed in a cup of water, then wait 30 minutes before brushing your teeth. 
Certain conditions may also affect your oral health, including:
Depending on the type of orthodontic treatment, your braces may have brackets, bands, and wires. In this case, it is important to avoid eating hard or sticky food. This includes things like nuts, popcorn, hard candy or gum, which could break or displace parts of your orthodontics and potentially delay your treatment. Enjoying pasta, soft veggies, fruits, and dairy products are good choices. Having good oral hygiene is key in making sure tooth decay do not form around the braces. This means making sure the teeth and braces are thoroughly cleaned of food debris so that plaque does not accumulate. Allowing plaque to build-up can cause white spots on the surfaces of the teeth. You can ask your dentist for tips on how to maintain good oral hygiene.
If you have clear trays or aligners that are removable, you should always remove your trays before eating or drinking any liquid other than water. Regardless of whether food is hard or soft, removing your tray before eating helps to ensure effectiveness of your treatment.
If you wear dentures, adjusting to what and how you eat can be a major challenge. When you first get dentures, your mouth and tissue need time to adjust to chewing and biting. Starting with soft foods like soups, smoothies, and applesauce for your first few meals can help make the transition more comfortable. Be mindful of hot dishes and drinks as it can sometimes be difficult to gauge the temperature of your food. After a couple of days, you can move onto more solid foods as your mouth begins to adjust to the dentures. Take care to avoid hard or sticky food and tough meats which could break or damage your dentures. Denture-friendly foods include slow-cooked or ground meats, cooked fish, ripe fruits, and cooked vegetables. A good tip is that if you can cut the food with a fork, chances are the food will not damage your dentures.
Dry mouth or xerostomia can make it difficult to talk, chew, and swallow food. Symptoms of dry mouth may include increased thirst, sore mouth and tongue, difficulty swallowing and talking, and changes in taste.  If you are experiencing a dry mouth, it is important to talk to your oral health care provider (as well as primary care provider) to better understand the potential causes and management. Regardless of the cause, you have lots of options for making it easier to eat. First, ensure that you drink plenty of fluids and sip cold water between meals. Chew your food well if you’re having trouble swallowing and only take small bites. Combining solid foods with liquid foods such as yogurt, gravy, sauces, or milk can also help. You want to avoid foods that are acidic, hot, or spicy as these may irritate your mouth further. Good oral care also plays a key role in alleviating dry mouth and preventing tooth decay, which is a common oral complication of dry mouth.
Here are some actions you can take to support good oral health: 
As growing research and studies reveal the link between oral health and overall health, it becomes more evident that taking care of your teeth isn’t just about having a nice smile and pleasant breath. Studies show that poor oral health is linked to heart disease, diabetes, pregnancy complications, and more, while positive oral health can enhance both mental and overall health. Good oral hygiene and regular visits to the dentist, combined with a healthy lifestyle and avoiding risks like excess sugar and smoking, help to keep your smile and body healthy.
The contents of this website are for educational purposes and are not intended to offer personal medical advice. You should seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website. The Nutrition Source does not recommend or endorse any products.
Use healthy oils (like olive and canola oil) for cooking, on salad, and at the table. Limit butter. Avoid trans fat.
Drink water, tea, or coffee (with little or no sugar). Limit milk/dairy (1-2 servings/day) and juice (1 small glass/day). Avoid sugary drinks.
The more veggies — and the greater the variety — the better. Potatoes and French fries don’t count.
Eat plenty of fruits of all colors
Choose fish, poultry, beans, and nuts; limit red meat and cheese; avoid bacon, cold cuts, and other processed meats.
Eat a variety of whole grains (like whole-wheat bread, whole-grain pasta, and brown rice). Limit refined grains (like white rice and white bread).
Incorporate physical activity into your daily routine.
Create healthy, balanced meals using this visual guide as a blueprint.
Thank you for supporting our mission of translating food and nutrition knowledge into daily practice!
Make a gift
A monthly update filled with nutrition news and tips from Harvard experts—all designed to help you eat healthier. Sign up here.
Explore the downloadable guide with tips and strategies for healthy eating and healthy living.