Consuming more sugar does not necessarily mean you will suffer from more tooth decay, an expert has said.

Brushing, flossing and visiting the dentist twice a year are standard dental recommendations. However, there continues to be a number of myths about general dental health, according to Prof Carole Palmer of the Tufts University School of Dental Medicine in Boston. She set out to debunk these myths and explain how diet and nutrition affects everyone's oral health.

The first myth is that the consequences of poor oral health are only restricted to the mouth. Prof Palmer pointed out that in reality, what pregnant women eat may affect the tooth development of their unborn baby. In fact, poor nutrition during pregnancy may make the unborn child more likely to have tooth decay later in life.

"Between the ages of 14 weeks to four months, deficiencies in calcium, vitamin D, vitamin A, protein and calories could result in oral defects (in the foetus)," Prof Palmer said.

Some data also suggest that a lack of adequate vitamin B6 or B12 could be a risk factor for cleft lip and cleft palate formation.

The second myth is that more sugar means more tooth decay. According to Prof Palmer, it is not the amount of sugar you eat, but the amount of time that this sugar is in contact with your teeth.

"Foods such as slowly-dissolving candies and soda are in the mouth for longer periods of time. This increases the amount of time teeth are exposed to the acids formed by oral bacteria from the sugars," she explained.

The third myth is that losing baby teeth to tooth decay is ok, as you are going to lose these teeth anyway. However Prof Palmer noted that tooth decay in baby teeth can result in damage to the developing crowns of the permanent teeth developing below them. Furthermore, if baby teeth are lost prematurely, the permanent teeth may erupt in the wrong position and require orthodontics later on.

The fourth myth is that osteoporosis only affects bones such as the spine and hips. Prof Palmer pointed out that this condition may also lead to tooth loss because teeth are held in the jaw by the face bone, which can also be affected by osteoporosis.

"So the jaw can also suffer the consequences of a diet lacking essential nutrients such as calcium and vitamins D and K. The jawbone, gums, lips, and soft and hard palates are constantly replenishing themselves throughout life. A good diet is required to keep the mouth and supporting structures in optimal shape," Prof Palmer said.

The fifth myth is that dentures improve a person's diet. The reality is that if dentures do not fit well, older adults tend to eat foods that are easy to chew and low in nutritional quality, such as cakes or pastries.

"First, denture wearers should make sure that dentures are fitted properly. In the meantime, if they are having difficulty chewing or have mouth discomfort, they can still eat nutritious foods by having cooked vegetables instead of raw, canned fruits instead of raw, and ground beef instead of steak. Also, they should drink plenty of fluids or chew sugar-free gum to prevent dry mouth," Prof Palmer advised.

The final myth is that decay is only a young person's problem. In fact, in adults and older people, receding gums can result in root decay (decay along the roots of teeth).

Commonly used drugs such as antidepressants, diuretics, antihistamines and sedatives increase the risk of tooth decay by reducing saliva production.

"Lack of saliva means that the mouth is cleansed more slowly. This increases the risk of oral problems. In this case, drinking water frequently can help cleanse the mouth," Prof Palmer said.

Adults and older people are more likely to have chronic health conditions, like diabetes, and these are risk factors for periodontal (gum) disease, which begins with an inflammation of the gums and can lead to tooth loss.

"Type 2 diabetes patients have twice the risk of developing periodontal disease of people without diabetes. Furthermore, periodontal disease exacerbates diabetes mellitus, so meticulous oral hygiene can help improve diabetes control," Prof Palmer added.

Details of these findings appear in the journal, Nutrition Today.