1. Vegetables: dark-green vegetables, starchy vegetables, red and orange vegetables
2. Fruits: whole apples, pears, berries, citrus, melons
3. Nonfat or low-fat dairy products: milk, yogurt, kefir, cheese
4. Whole grains: whole-wheat flour, bulgur (cracked wheat), oatmeal, whole cornmeal, and brown rice
5. Lean sources of protein: meat, poultry, seafood, beans (edamame provides complete protein) and peas, eggs, quinoa, processed soy products like tofu, nuts, and seeds

• Fiber-rich fruits and vegetables: Foods with fiber have a scrubbing, detergent effect in your mouth, notes the American Dental Association (ADA). They also stimulate saliva flow which is your best natural defense against cavities and gum disease. About 20 minutes after you eat something containing sugars or starches, your saliva begins to neutralize the acids and enzymes attacking your teeth. Because saliva contains traces of calcium and phosphate, it also restores minerals to areas of teeth that have lost them from bacterial acids.
• Cheese, milk, plain yogurt, plain kefir and other dairy products: Cheese is another saliva generator. Calcium in cheese, as well as, calcium and phosphates in milk and other dairy products help replace minerals your teeth might have lost due to other foods.
• Green and black teas: Both contain polyphenols that interact with plaque bacteria. Polyphenols either kill or suppress bacteria, preventing them from growing or producing tooth-attacking acid. Depending on the water you use to brew tea, a cup of tea can also be a source of fluoride.
• Chew gum with the ADA Seal: Chewing sugarless gum for 20 minutes after meals helps reduce tooth decay, because increased saliva flow washes out food and neutralizes acid produced by dental plaque bacteria.
• Foods with fluoride: Fluoridated drinking water and products made with fluoridated water (powdered milk, juices [as long as they don’t contain much sugar], dehydrated soups), help protect teeth.  Some commercially-prepared foods, such as poultry products, seafood, and powdered cereals, provide fluoride.
• Avoid snacks and drinks that are high in sugar: Instead, replace one snack a day with a healthier choice.
• Keep fruits and vegetables at home to offer as healthy snacks, instead of less nutritious carbohydrates: Choose fruits and vegetables containing a high volume of water, such as apples, clementines, melon, oranges, pears, carrots, celery, cucumbers, tomatoes, and salad greens. Limit bananas, raisins, and other dried fruits which contain concentrated sugar, or urge your child to brush after such fruits are eaten.
• Serve cheese with lunch or as a snack: Cheese, especially cheddar, Monterey Jack, Swiss, and other aged cheeses help increase saliva flow which washes many food particles away from teeth.
• Avoid or limit sticky, chewy foods: Raisins, dates, dried figs, granola bars, oatmeal or peanut butter cookies, jelly beans, caramel, honey, molasses, and syrup stick to teeth, making it difficult for saliva to wash them away. If your child consumes these types of foods, have him/her brush their teeth immediately after eating.
• If you give your child a sweet, offer it as dessert right after a meal: The increased amount of saliva still in the mouth after a meal can help wash the sweet away from teeth. Water also washes away food particles remaining on teeth.
• Limit between-meal snacks: If you crave a snack, choose something nutritious like unsweetened yogurt, celery, carrots, an apple or pear. Rinse your mouth with water or chew sugarless gum afterward to increase saliva flow and wash out food and acid.
• Get your family in the habit of eating as few snacks as possible: Snacking frequency is far more important than the quantity consumed. Time between meals allows saliva to wash away food particles that bacteria would otherwise feast on. Frequent snacking, without brushing immediately afterwards, provides constant fuel to feed bacteria, and promotes plaque development and tooth decay. Limit snacks to no more than 1 or 2 a day. Brush teeth after consuming a snack, if possible.
• Eat fewer foods containing sugars and starches between meals: Instead, eat nutritious foods, like cheese, raw vegetables, plain yogurt, or a firm fruit (apple, pear).
• Avoid sugary foods that linger on teeth: Lollipops, hard candies, cough drops, and mints all contribute to tooth decay, since they continuously coat teeth with sugar.
• Buy foods that are sugar-free or unsweetened.
• Offer your child plain water instead of juice or soda: Juices, sodas, and even milk contain sugar. Water does not harm teeth and helps to wash away food particles clinging to teeth.
• Include good sources of calcium in your child’s diet to build strong teeth, like milk, yogurt, cheese, broccoli, green leafy vegetables, beans, and legumes.
• If your child chews gum, encourage him/her to choose xylitol-sweetened or sugar-free gum: Xylitol has been shown to reduce the amount of bacteria in the mouth and the chewing action helps increase the flow of saliva.
• Use fluoride and brush and floss your child’s teeth: The best way to prevent tooth decay is to use a fluoride toothpaste every day. The fluoride seeps inside the tooth to reverse early decay. Brush your child’s teeth at least twice a day and after each meal or snack if possible. If brushing between meals is not possible, at least rinse the mouth with water several times. Floss your child’s teeth at least once a day to help remove particles between teeth and below the gum line.
• Brush your child’s teeth after giving him/her medicine: Medicines such as cough syrups contain sugar that mouth bacteria use to make acids. These acids can eat away at the enamel, the protective outer layer of each tooth.
• Visit your dentist for regular check-ups and cleanings twice each year: Schedule your child’s first visit to the dentist by age 1 or within six months of the first tooth breaking through the gums. Regular dental check-ups can help find any developing dental problems early.
• Avoid bedtime bottles: Never put your baby to bed with a bottle filled with milk, formula, juice, or soda. Such bottles at bedtime increase the risk of “Baby Bottle Tooth Decay,” early dental decay in a baby’s mouth. Prolonged exposure of milk or other sugar to mouth bacteria will cause tooth enamel to deteriorate and increase the risk of tooth decay. Find alternative methods to help your baby sleep before bedtime. If your baby needs a bottle at bedtime, fill it with plain water instead.
• Milk and other dairy products: The primary dietary source of calcium which is essential for healthy teeth. Calcium is the key ingredient in a mineral known as hydroxyapatite that strengthens tooth enamel, as well as bones. Dairy products, especially cheese, also contain casein, a type of protein. Casein and calcium play an important role in stabilizing and repairing tooth enamel.
• High fiber foods: Leafy green vegetables, beans and lentils, nuts and seeds and other high fiber foods often provide calcium, and promote good digestion, healthy cholesterol levels, and healthy teeth, mostly because they require a lot of chewing. Chewing generates saliva, and these foods physically scrub your teeth as they are mashed into little pieces.
• Strawberries: These contain malic acid, a natural enamel whitener. To make your own at-home whitening treatment: Crush a strawberry to a pulp, mix it with baking soda, and spread it on your teeth using a soft toothbrush. Five minutes later, brush it off, rinse, and see a whiter smile. Be sure to floss, since tiny strawberry seeds may get trapped between teeth.
• Sugar-free gum: Helps clean teeth by stimulating saliva production. Saliva is nature’s way of washing away acids produced by bacteria in your mouth, and it also bathes the teeth in bone-strengthening calcium and phosphate. Many varieties of sugarless gum are sweetened with xylitol, an alcohol that reduces bacteria. Mint flavors may be best, however, since a 2011 study suggests that the acid used to create certain fruit flavors could damage teeth, though only slightly. Anything that tastes sour is usually more acidic, even if promoting saliva flow.
• Consume sugary foods with meals: Your mouth produces more saliva during meals which helps to neutralize acid production and rinse food particles from the mouth.

For healthier gums:

• Avoid or limit acidic foods like coffee: Bacteria and other pathogenic microorganisms thrive in an acidic environment and can contribute to gum disease, inflammation and receding. Excessively acidic foods can also damage the protective enamel layer of your teeth. Examples of acidic foods and beverages include excessive consumption of meats, citrus fruits, white bread, pasta made with white flour, pickled and fermented foods, alcoholic beverages, coffee and black tea.
• Avoid sugary foods and beverages which coat the teeth and gums: Sugary foods are highly acidic and provide bacteria with an easy food source, which is why excessive consumption of sugar greatly increases the incidence of dental cavities and gum diseases. Examples include cakes, candy,  chocolate, donuts, muffins, energy drinks, sodas, and liqueurs. Chewy carbohydrates with gluten, like white bread and donuts, may stick to teeth, get caught between teeth and gums when they recede, and contribute to gingivitis or gum-tissue inflammation.
• Avoid cold foods: Cold foods may cause sensitivity. When gums recede, the nerves that supply your teeth are exposed, which make them more sensitive to cold foods and beverages. Avoiding colds foods such as ice cream, snow cones, popsicles, ice cubes, and refrigerated fruits and vegetables may reduce some of the pain that is commonly associated with receding gums. Crunching on ice cubes, or any hard foods such as nuts, may loosen or crack teeth that have become weak due to receding gums. Instead, eat or drink room temperature or heated items that are soft in texture. Ask your dentist about special toothpastes designed to reduce tooth sensitivity.

The worst foods and habits for teeth and gums:

• Chewy, sticky candies and sweets: If you eat sweets, choose those that clear out of your mouth quickly. Avoid lollipops, caramels, cough drops, and other sweets containing refined sugar. Effects of chocolate on preventing cavities have been indicated by studies funded by the candy industry, but not conclusively proven. Remember, much commercial chocolate still contains refined sugar.

1. Chewy candy: The stickier the candy, the worse it tends to be for teeth. Extra-chewy candies (taffy, caramels, Jujyfruits) stick to and in-between teeth for a long time, allowing bacteria in your mouth to feast leisurely on the deposited sugar. Bacteria break down this sugar to make acid which dissolves the protective layer of tooth enamel and causes cavities. Candies that are chewy, sugary, and acidic—a category that includes many “sour” varieties—are especially harmful, since they already contain erosive acid, in addition to that produced by the interaction of sugar and bacteria.
2. Hard candies: While hard candies don’t cling to teeth as readily as chewy candy, they are still harmful to your mouth. Unlike chocolate-based sweets which are chewed quickly and wash away relatively easily, hard candy dissolves slowly and saturates your mouth for several minutes, giving bacteria more time to produce harmful acid. Additionally, many varieties of hard candy are flavored with citric acid. Some hard candies can actually chip your teeth.
3. Sticky, sour candy: Sour candy is worse than sweet candy, because sour candy has just as much sugar, plus added citric acid, and tends to cling to teeth longer.

• Cough drops: Although meant for medicinal purposes, cough drops have a high sugar content. Sucking on them all day to soothe the throat bathes your teeth in sugar. Dental plaque (which contains bacteria) increases in the mouth, creating a higher risk of decay and gum disease. Try to buy sugar-free cough drops instead.
• Starchy foods that can get stuck between teeth, such as processed carbohydrates: Soft white breads, cakes, cookies, crackers, danish, muffins, potato chips, etc., are all carbohydrates that can get trapped between teeth. Your saliva provides an enzyme called salivary amylase that begins the digestive process in your mouth, turning these carbohydrates into sugar. If you snack on such foods all day, you’re constantly keeping sugar in your mouth. Sugar is bad, because bacteria that are naturally in your mouth eat the sugar and create acid. If you had no plaque (which is impossible!), then there wouldn’t be anything to break down sugars to create the acids which cause tooth decay.
• Constant snacking throughout the day: Enables food debris and plaque to stay on your teeth for a prolonged amount of time. When hungry, snack on cleansing-type foods such as apples, pears, clementines, carrots, and celery that minimize plaque buildup.
• Sports and energy drinks: Contain a high amount of sugar and cause more acid damage to teeth than soda (Sports drinks first, energy drinks second, soda third). It depends on the type of sports drink; some contain more citric acid than others. Water is still your healthiest, thirst-quenching beverage.
• Carbonated soft drinks: The leading source of added sugar among kids and teens. Besides being sugar-laden, most soft drinks contain phosphoric acid and citric acid both of which which erode tooth enamel and can lead to teeth sensitivity. High sugar and acid content are horrible for your teeth! The sugar, often high fructose corn syrup, feeds bacteria which produce additional acid. Sipping may be worse than gulping soda down, since sipping prolongs the low (acidic) pH in your mouth. Frequent soda drinking bathes the teeth in sugar and promotes dental decay. If you must drink soda, lessen the amount and frequency, and drink water instead. Minimize tooth enamel erosion by rinsing with water after your teeth have been exposed to acidic beverages. Sip acidic drinks through a straw to minimize contact with the teeth. Wait at least 30 minutes before brushing with a soft toothbrush after acid exposure to avoid further breakdown of your enamel.
• Fruit juice: Although generally healthy due to it’s vitamin and mineral content, naturally sweet fruit juice still contains a high amount of sugar. For example, apple juice contains approximately as much sugar as the same volume of soda! Diluting fruit juice with water can help reduce sugar content and minimize sugar exposure to your teeth. Choose whole fruit instead of juice when possible to obtain more nutrients and fiber with less sugar per serving.
• Substances that dry out your mouth: These include alcohol and many medicines. Anything that dries the mouth increases the risk of dental plaque. If medications are the cause, talk with your health care provider about getting a fluoride rinse, or a fluoride gel with which to brush your teeth.
• Pickles: Acid, typically provided by vinegar, is essential to the pickling process, giving pickles their sour, salty taste. It’s also what makes pickles a potential hazard to tooth enamel. Eating them more than once a day increases the risk of enamel wear by about 85%. Most people don’t eat pickles that often, however. Snacking on them in moderation may not noticeably affect dental health.
• Alcohol: Saliva is one of our first defenses to dilute plaque and acids. It also has anti-bacterial properties. People who drink a lot of alcohol tend to have very dry mouths. If you already suffer from dry mouth, drinking alcohol will make it worse.
• Wine: Anything that will stain a white table cloth will also stain teeth. Red wine contains substances known as chromogens that produce tooth-discoloring pigments. Furthermore, tannins in red wine tend to dry out the mouth and make teeth sticky, worsening stains. Even white wine may contribute to staining. Reds and whites both contain erosive acid, enabling stains from other foods or drinks to penetrate teeth more deeply.
• Crackers and chips: Refined carbohydrates in saltines, crackers and chips are converted to sugar in the mouth very quickly, providing food for cavity-forming bacteria. Crackers also become mushy and sticky when chewed and fill spaces between your molars and teeth. Eating them in moderation is not likely to cause long-term problems, as long as you thoroughly brush and floss afterward.
• Coffee: The brown stains that accumulate inside of a coffee mug are an example of how coffee drinking can stain your teeth over time. Coffee-stained teeth may become resistant to toothbrushing and more likely to be discolored again following a bleach treatment. Teeth with heavy coffee stains also tend to be sticky and attract food particles and bacteria.
• Tea: Some black teas stain teeth more easily than coffee. Like red wine, black teas tend to have a high tannin content which promotes staining. Teas with fewer tannins, like green tea, white tea, and herbal tea, are not as likely to discolor teeth.
• Citrus fruits and juices: A rich source of vitamin C, potassium, and other nutrients and good for you in many ways, but not for your teeth. Grapefruit and lemon juice are highly acidic and can erode tooth enamel over time. Orange juice tends to be less acidic, and many store-bought varieties are also fortified with teeth-friendly calcium and vitamin D. Always brush and floss as recommended after ingesting these.
• Lemons and limes: The pH of straight lemons is 2. Sucking on lemons or limes with your front teeth hastens erosion of enamel from their front surface, yellowing and sensitivity.
• Dried fruit: Contains the same amount of sugar as fruit that hasn’t been dried, plus it’s sticky and stays on your teeth.
• Kombucha: A pH less than 7 is acidic. Kombucha’s pH is very low, about 2.5! Drinking this daily or often is likely to cause dental problems.
• Vomit/acid reflux/bulemia: Such conditions can erode the insides of one’s teeth in a specific pattern by exposing teeth to an acidic bath of food that has already been digested.
• Binge eating: This usually involves ingesting large amounts of sugary foods and drinks, which may lead to dental decay. Binge eating may also occur with another eating disorder such as bulimia where food is purged with vomiting. Because vomit is highly acidic, it can erode and damage teeth over time. Medical care and intervention is important to address such eating disorders.
• Ice and frozen, or very cold, foods: Chewing ice is a seemingly harmless, unconscious habit but not good for teeth, since ice is so hard! It can easily dislodge a large, old filling or cause permanent damage to teeth with tiny cracks. These cracks can grow larger over time and ultimately cause a tooth to fracture. Select chilled water or drinks without ice to resist the urge to chew it. Coldness can also make teeth slightly more brittle. Remember, your mouth is generally warm. If you chew or bite on anything very dense, hard, or cold, like frozen nuts or pastries, etc., you may damage a tooth.
• Smoking: Tobacco use dries out the mouth and increases the amount of plaque buildup around teeth. Smokers are more likely to lose teeth compared to nonsmokers due to gum disease. Also, tobacco use increases your risk of oral cancer. Seek help from your doctor or a support group to end this unhealthy habit.
• Playing sports without a mouth guard or protection: Teeth are vulnerable to being damaged or knocked out during high impact sports like basketball, football, hockey, lacrosse, soccer, and wrestling, A proper sports helmet or mouth guard can help to cushion blows to the mouth, jaw, and head.
• Tongue piercings: Highly discouraged by dentists, tongue piercings can negatively affect your health, and cause teeth to chip, break, and require dental work. Mouth jewelry encourages more bacteria buildup in the mouth and may also rub against the gums, causing permanent gum recession which can lead to sensitivity and even tooth loss.

While eating healthy foods and avoiding snacks and drinks that are high in sugar are good ways to prevent cavities, a good dental regime is essential for maintaining healthy teeth and gums. 

Remove plaque by brushing and flossing thoroughly, and visit your dentist regularly to detect any signs of early decay.

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