Why does toothpaste contain fluoride?

Fluoride belongs to the so-called trace elements. In small amounts, fluoride has positive effects on our bones and teeth, but in large amounts it can also have negative effects. 
Not only does it harden the bones in our body, but also our tooth enamel. Supplying the body with sufficient fluoride is therefore important to prevent tooth decay (also called cavities or dental caries). In children, however, excessive fluoride can lead to dental fluorosis. This dental disorder is characterised by tooth discoloration that can range from white spots to brown stains on the tooth enamel. Not only is this a cosmetic concern; dental fluorosis can also reduce the enamel’s resistance to dental caries. 
Weleda is a company inspired by anthroposophy and incorporates its principles into the development of its products. In anthroposophic medicine, the human being is considered holistically as the unity of body, mind and soul. The mineral fluoride represents in this respect a strong impulse that can lead to hardening and possibly impair development. From this point of view, people should be able to make a conscious decision about how much fluoride they want to ingest.
 

Each person has a different tooth structure, and therefore requires a different amount of fluoride. Experts consider an adequate intake to be 0.05 mg fluoride per kg body weight per day. This includes food and drink, but also toothpaste and mouthwash. This means that the consumption of fluoride-containing foods such as fish, cereals, milk, dairy products and nuts, in particular walnuts, or the use of fluoridated salt in cooking or fluoridated drinking water may already cover the individually required dose of fluoride.

The fluoride content in toothpaste is regulated by law: adult toothpastes may contain a maximum of 0.15% (1500 ppm, parts per million). These amounts are also recommended by dentists for children 6 years and older. Junior toothpastes (6 years and older) and adult toothpastes therefore usually only differ in taste. 
Starting from a dose of 0.1 mg fluoride per kg body weight per day, dental fluorosis may occur in teeth that have not yet broken through. For toothpastes for smaller children (under 6 years), the maximum recommended amount is therefore lower (0.05%). 
 

As noted above, fluoride can easily be overdosed, and particular care should be taken if fluoride supplements (e.g. tablets or drops, etc.) have been prescribed by a paediatrician or dentist. The administration of fluoride is indicated in individual cases of deficiency symptoms. A doctor should determine the dosage and duration of the treatment individually, taking into account the fluoride intake from other sources.
For these reasons, Weleda does not use water-soluble fluoride in its oral care products, but offers consumers an alternative to fluoride products.
 

Each salt has different properties, such as its solubility in water. For example, calcium fluoride (feldspar, fluorite) is a naturally occurring mineral which is insoluble in water, while sodium fluoride is soluble in water.
Toothpaste containing fluoride contains water-soluble fluorine compounds, often sodium monofluorophosphate, amine fluoride and stannous fluoride. These are produced in a synthetic process. 
Two Weleda dental care products contain naturally occurring, water-insoluble calcium fluoride, in a highly diluted form.