At around six months of age, but not before four months old, infants start receiving semi-solid foods known as complementary feeding, mixed feeding or weaning. The introduction of semi-solid foods is important because infants start to become physiologically and developmentally ready for these foods, and their growing body require more nutrients than cannot be provided by breastmilk or formula alone. For example, their muscles increase in size and strength, their digestive system is able to process more solid forms as it develops motility and immune tolerance. In addition, their brains are forming new connections every day, as they develop observation, memory and vocal skills.
Throughout complementary feeding, nutritious foods can be introduced in any order, or at any rate, provided the texture is suitable for your own infant’s stage of development. A balanced and regular supply of sources of protein, fats and carbohydrates are required as their behaviour changes with increasing appetite and growth requirements.
These include simple and complex sugars. Carbohydrates are essential because they supply energy for all body functions, including all physical and mental processes. Breastmilk is a natural contributor of simple carbohydrates including lactose and galactose, providing a readily usable form of sugars that can be converted to glucose (the main energy forming carbohydrate of the body) and also feeding the developing infant gut microbiome. Complementary foods including cereals (e.g. rice, oats), fruits (e.g. apple, banana) and vegetables (e.g. sweet potato, carrots) provide more complex carbohydrates for sustained energy and act as a source of dietary fibre to assist with digestion. In addition to breastmilk or infant formula, complementary feeding will help meet an infant’s carbohydrate needs after 6 months of age.
Fats are a major source of energy for infants and are required for normal brain and eye development, as well as for immunity and resistance to infections. Fats are actually much richer in energy than carbohydrates, containing about 6 times the caloric value. Infants are different to adults in that they have a higher level of stored fat which serves as insulation to reduce body heat loss, and as padding to protect the infant’s body. Breastmilk contains approximately 4% fats, in the form of omega-3 and omega-6 fatty acids, in highly absorbable forms that get across the gut very easily. As mixed feeding begins, food sources such as meats, poultry, dairy products, eggs and oils contribute further to the diversity of fatty acid that growing tissues are exposed to.
Protein is important to build, maintain and repair infant tissues and to manufacture important enzymes and hormones among other roles. The highest protein demands are in growing muscle tissue, however protein is broken down to amino acids that supply newly forming tissues in all parts of the body, such as the blood and skin. Before an infant is six months old, breastmilk and infant formula provide enough soluble proteins in the form of casein, albumins and globulins to meet an infant’s needs. During complementary feeding, good sources of protein in addition to breast or formula milk include meat, poultry, fish, dairy products and eggs. When an infant starts receiving a substantial portion of their nutritional intake from foods other than breast or formula milk, these complementary foods need to provide adequate levels of protein from a diverse range of quality sources.
Micronutrients are essential for growth, providing bulk nutrition to support short-term and long-term energy needs (fats, carbohydrates) and for building tissue strength, size and functionality (protein). All three sources need to be included as part of a healthy diet for 6-12 month old babies.
References and links
- Kathy C. Complementary feeding for infants 6 to 12 months. The journal of family health care. 2010;20(1):20-23.
- Hermoso M, Tabacchi G, Iglesia‐Altaba I, et al. The nutritional requirements of infants. Towards EU alignment of reference values: the EURRECA network. Maternal & child nutrition. 2010;6:55-83.