Breast milk provides an infant with dietary fuel and nutrients as well as the building blocks for cell division, tissue growth, and the maturing of organ systems throughout the body. Approximately half of the calories a baby receives in breast milk are from fat. Babies need more fat than a child or adult because infants have higher energy needs but only a very limited stomach capacity. Fat is also important for the absorption of certain vitamins. Carbohydrates, too, provide a major source of calories to fuel an infant’s growth, though they are not as energy dense (a gram of fat provides more than twice the calories of a gram of protein or carbohydrate).

In addition to fuel for growth, an infant needs biological building blocks. One key source of building blocks is protein. The protein needs of a baby, like the baby’s fat needs, are also much higher than an adult’s. Once inside the baby’s digestive system, proteins are broken down into smaller peptides and, eventually, to their component amino acids. Proteins are a key source of nitrogen for the baby’s body and also provide the raw materials for muscle, skin, connective tissues, and organ systems.

Protein
There are thousands of different proteins in the human body, but they are all combinations of fewer than two dozen common amino acids. Some of these amino acid building blocks can be made by tissues in the body from even smaller components. Nine of the amino acids, however, cannot be synthesized in the body and therefore must be obtained through the diet. These are called “essential amino acids.”

Proteins are required for the building, maintenance, and repair of tissues throughout the infant’s body. Most people equate protein with muscle, but protein is really a component of all tissues. Proteins are also necessary as a source of building blocks for digestive enzymes, regulatory hormones, growth factors, and important components of the immune system, such as antibodies.

Carbohydrates
Carbohydrates are necessary to supply food energy for growth, body functions, and activity, as well as to facilitate the efficient use of protein and fat in the diet. Carbohydrates are also building blocks for some essential body compounds. Nucleotides, for example, are compounds made up of a sugar (a simple carbohydrate) plus a nitrogen base (a component of protein) and a phosphate group. Nucleotides, in turn, are the building blocks of DNA and RNA, the genetic instructions that guide the cellular development, division, and function of all living organisms.

Fat
The functions of lipids are to provide energy; serve as insulation to reduce body heat loss; provide padding to protect the infant from injury; facilitate the absorption of the fat-soluble vitamins A, D, E, and K; and provide fatty acids that are critical for normal brain and eye development as well as healthy skin, hair, and immune function.

There are also fatty acids in breast milk, such as DHA, that play critical roles in the development of the visual system and the brain. The concentration of DHA in breast milk is low, generally between 0.2 % and 1.0% of total fat. DHA concentration can vary dramatically, by a factor of 10 or more, depending on the amount of DHA a woman eats (it’s most commonly found in seafood). But even though its concentration varies, DHA still represents a very small percent of the total fat content in milk. That’s because most of the fats in breast milk are burned as fuel. DHA, on the other hand, is used a structural component in cell membranes, including those of the brain and retina.

Vitamins & Minerals
The growth, development, function, and health of every tissue and organ system in the body depend on vitamins and minerals, along with other nutrients. Vitamins such as A, C, B6, B12, E, and folate, as well as minerals such as iron, selenium, and zinc play important roles in the health and development of the immune system. Vitamins including B12 and minerals like iron and iodine are essential for neurological development. Vitamins and minerals play a range of important roles in the development of the infant's gastrointestinal system. Many different vitamins and minerals are essential for the development, growth, and functioning of the circulatory system: iron and magnesium, for example, are essential for the production of the trillions of red blood cells that pick up oxygen and carry it to cells throughout the body. Copper, along with vitamins A, C, and E, riboflavin, folate, choline, and calcium, is required for hemoglobin synthesis as well as for the production of collagen in capillary walls.

More on this topic

Mother's Milk (VIDEO)
The Best Start
The Ultimate Homemade Meal
Baby's Nutrition Begins with You
Local & Imported Ingredients
Meals Made to Order
Ingredients May Vary
Feeding Cycle
Designed for Growth
Recipe to Develop
The Closest Bond


Related Health Centers:

Infant Nutrition Health Center, Mother-Baby Bond Health Center, Mother’s Milk Health Center, Monthly Infant Development Calendar Health Center,Weekly Pregnancy Calendar Health Center