Natural sources of fluoride are tea, meat, fish, cereals and fruit. But fluoride content in these foods depends primarily on the areas of their origin, and how much fluoride is in the soil in which to grow. Drinking water contains significant amounts of fluoride. A certain amount of ingested fluorine is by toothpaste.

Fluoride content in food products

Foodstuff micrograms per 100 g of food
Tea 1,41
Oats 10,6
Rice 5,9
Cheese 5,0
Coffee 5,0
Pasta 4,6
Potatoes, mashed 4,3
Spinach 3,7
Peas, cooked 3,0
Meat – veal 2,3
Meat – pork 2,1
Fish – baked 1,0

In developed countries, fluoride is added to drinking water at a concentration of 1 ppm (parts per million). In this way it is intaked about 1-2 mg of fluoride per day.