The German word beikost translates as "foods other than milk or formula." It refers to the first strained foods that are given to a young infant as a supplement to breast milk or formula. Beikost is introduced between four and six months of age, when an infant develops the appropriate oral motor skills and can indicate disinterest by leaning back and turning away. The first foods introduced vary by country, but are generally soft mashed foods that are easily digested. If solid foods are added before four months, there is a risk of overfeeding or negative physical reactions such as diarrhea.
see also Infant Nutrition.