Fats have received a bad reputation over the last decade, resulting in a plethora of low-fat diet programs and fat-free food products. While certain types of fats or excessively high amounts can be problematic, fats are actually vital to your body. They are essential components of all body tissues and are especially important in the development of cell membranes, the retina and brain tissue. Your body requires fats and oils to support proper growth and development, particularly during infancy and childhood.
Fat supplies nine kilocalories per gram, making it the most energy-dense macronutrient. During certain periods of infancy, childhood and adolescence, the body needs additional calories to support growth spurts and development. Consuming healthy fats – the monounsaturated and polyunsaturated types – can supply the extra calories needed during that time. Your body also uses stored fat to provide energy during times of starvation or illness.
Essential fatty acids
Essential fatty acids are a particular type of fat. There are two essential fatty acids: linoleic acid and alpha-linolenic acid. Your body requires that you consume these through foods, since you cannot produce them endogenously. The body utilizes these fatty acids for tissue development and to produce chemicals in the body that regulate physiological functions, such as the inflammatory response and blood pressure. Essential fatty acid deficiency in children can cause growth faltering, abnormal vision and skin problems.
Absorption of vitamins
Vitamins A, D, E and K are fat-soluble, meaning that you need fat to absorb them properly. If you cut out fat completely, you can develop deficiencies of these vitamins. Vitamin deficiencies may cause many problems, such as night blindness from a lack of Vitamin A or weak bones from a lack of Vitamin D.
Cognitive function and vision
Docosahexaenoic acid – or DHA -- is a fatty acid that is important to brain and retinal development in infants and children. During the last trimester of pregnancy and the first year of life, a child’s brain undergoes a rapid growth spurt during which large amounts of DHA are accumulated in this area. Adults can synthesize DHA from alpha-linolenic acid. However, the conversion process in infants is very limited – only 1 to 5 percent of alpha-linolenic acid can be converted to DHA, according to the Food and Agriculture Organization of the United Nations.
Breast milk provides DHA for infants, but the amount in milk depends on maternal intake. It may be important for lactating women to consume foods rich in DHA to support infant development. Though study results are not always consistent, a 2009 review published in "Prostaglandins, Leukotrienes and Essential Fatty Acids" reported higher levels of breast milk DHA were usually associated with better neurodevelopment and visual function.
Fats help to protect vital organs inside the body by providing a layer of cushioning. They also insulate the body and regulate body temperature. Fats slow gastric emptying and prolong satiety, which can help both children and adults feel more satisfied with their meal.
According to the Food and Agriculture Organization of the United Nations, infants up to 6 months need 40 to 60 percent of energy from fat. This is consistent with the amount in human breast milk and most formulas. The high fat content promotes growth, tissue deposition, and brain development. From 6 to 24 months, fat intake should gradually be reduced to approximately 35 percent of energy. After 2 years, children and adults should consume 25 to 35 percent of their calories from fat.