One of the greatest health achievements in the last 30 years has been the improvement in dental health - particularly in children.
The reason tooth decay has become much less common is due to the introduction of fluoride toothpaste around 1976 (König 2000; FAO/WHO 1998). The regular use of fluoride toothpaste seems to strengthen the tooth enamel and may also discourage the bacteria that produce the damaging acids.
Use of fluoride toothpaste should be started as soon as a baby’s first teeth appear. It is at this time that the damaging bacteria become established. They need to be discouraged especially at this time, because babies’ teeth are particularly susceptible to decay.
The most effective way of preventing dental decay (caries) is to brush morning and night with fluoride toothpaste (FDI 2000). This thorough and regular tooth care will help prevent the decay-promoting bacteria from getting established. Brushing last thing at night is particularly important, because the protective effect of saliva – nature’s mouthwash - is reduced during sleep, which means any food left around the teeth will have more of a chance to produce damaging acids. This means that after the teeth have been brushed at night it is best to drink only plain water.
A few areas of the country have enough fluoride in their water supply to reduce the risk of tooth decay. However, it is not wise to rely on this form of protection, as only one in ten people will receive this benefit. Furthermore, fluoride in the water reduces the risk of decay by about half, whereas regular fluoride toothpaste use seems to offer almost complete protection.
Eating or drinking any carbohydrate - both sugary sources such as sugar, fruit and juices, and starchy sources such as bread, rice, and pasta - may cause some damage to the teeth, if consumed too frequently. Fruit contains a number of sugars (sucrose, fructose and glucose) while starches are readily broken down by enzymes in saliva to glucose and maltose. Some of the bacteria in the mouth can use the sugars in food and drinks to produce acid that attacks the enamel surface of the teeth. Hence, a wide variety of carbohydrate-containing foods will contribute to the decay process if they are consumed too frequently.
Sugar and dental decay
Sugar can cause dental decay (caries) if consumed too frequently in foods and drinks (Cottrell 2005). However, the evidence available clearly shows that a wide variety of carbohydrate-containing foods will contribute to the decay process if used in this way (König and Navia 1995; FDI 2000).
There is no evidence that encouraging dietary abstinence reduces the risk of tooth decay (Kay and Locker 1996). Indeed, the exclusion of all sugar- and starch-containing foods would lead to a very unhealthy diet. Nonetheless, continuous eating and drinking ("grazing") is to be discouraged (FDI 2000).
Traditional recommendations to limit the amount of sugar consumed in the hope that this advice, even if followed, would lead to an appreciable reduction in the risk of dental caries, is no longer considered appropriate by most researchers (Food and Agriculture Organization/ World Health Organization 1998; Ruxton et al. 1999; Food and Nutrition Board 2002). The twice daily use of fluoride toothpaste is a more effective and more practicable means of achieving an acceptably low prevalence of this condition (Kay 1998; Gibson and Williams 1999).
The enamel will be repaired (using the calcium and phosphate present in saliva) provided some time elapses between acid attacks. Chewing stimulates the production of saliva and helps this repair process. Eating a small piece of cheese after a meal can also be beneficial, because cheese is alkaline in nature and so will help neutralize any lingering acid from both food and drink.
Carbohydrates, both starches and sugars, should still make-up the bulk of a healthy balanced diet, even when the focus is on dental health. It is not the amount of carbohydrates that is an issue for dental caries, but the frequency in which they are consumed. Constantly grazing, including young children continually feeding from a bottle, is not good for the teeth. The teeth need a rest between food and drink, so that they can repair themselves and thus prevent decay.
Research has shown us that if teeth are brushed regularly with fluoride toothpaste then they can cope with about five eating occasions a day - three meals and two snacks. Therefore, we can drink any beverage at meals, but between-meals its best not to continually sip-on acidic or sugary drinks such as juices, soft drinks and alcohol. Eating snacks, both fruit and confectionery, with meals or at set snack times, is a realistic and safe way to include them in the diet. It is nibbling fruit and sweets, or sipping from a bottle that contains a sugary drink, over a long period of time, that is harmful to teeth.
Nowadays, tooth decay is only one of the dental health concerns. Erosion of the tooth surface is increasingly being recognized as a growing problem. It can be caused by eating acidic foods, such as pickles, or sipping acidic drinks, like orange juice, too frequently. Although for health we should aim to eat at least five portions of fruit and vegetables a day, it is best to keep them to meal and 'official' snack times for the sake of the teeth. Too vigorous brushing of the teeth with a hard tooth brush will also cause very similar-looking damage.
Tooth decay can occur whenever the circumstances present themselves. The evidence is clear. Regular brushing of the teeth with fluoride toothpaste is the best way to prevent this. While there is little evidence that dietary advice produces an additional benefit, it is still sensible to remember to limit the frequency of carbohydrate food and drinks.
Traditional advice to limit the amount of sugar consumed in the hope that this advice, even if followed, would lead to an appreciable reduction in the risk of dental caries, is no longer thought to be helpful. The twice daily use of fluoride toothpaste is a more effective and more practicable means of achieving an acceptably low prevalence of this condition.