Nutritional Needs During the Lifecycle
All people need nutrients such as essential amino acids, carbohydrates and essential fatty acids (macronutrients), as well as vitamins and minerals (micronutrients) to sustain their body and health and obtain energy. Requirements for nutrients depend on a variety of factors among which their sex, age, activity level and health status. Inadequate intake of certain micronutrients is a common concern. At the same time growing prevalence of dietary excesses of energy, saturated fat, cholesterol, and refined carbohydrate is a concern. This fuels the current epidemics of obesity and chronic disease.
At international level (UN) experts have established recommendations for Dietary Recommended Intakes (DRI) that are specific for the various stages of life. These DRI form an important reference for assessing the quality of diets and elaborating nutrition education. However, individual variations due to health status and activity level should be taken into account. The table below provides DRI for energy and some mayor nutrients.
Table: Daily Recommended Intakes for Energy and Nutrients
|SEX/AGE||BODY WEIGHT||ENERGY||PROTEIN||IRON||ZINC||VITAMIN A||VITAMIN C||FOLATE|
|YEARS||Kg||kcal||MJ||g||Mg||mg||Mcg RE||mg||Mcg DFE|
|1 - 3||12.1||1022||4.28||14.0||6||8.4||400||30||160|
|4 - 6||18.2||1352||5.66||22.2||6||10.3||450||30||200|
|7 - 9||25.2||1698||7.10||25.2||9||11.3||500||35||300|
|60 and over||2142||8.96||41.0||11||9.8||600||45||400|
|60 and over||2496||10.44||49.0||14||14.0||600||45||400|
Source: FAO. Family Nutrition Guide. 2004
Variations during the Life Cycle
Infants only need breast milk during the first six months. It gives babies all the food and water they need during the first six months of life. Exclusive breastfeeding until the baby is six months old protects the baby against sicknesses (e.g. diarrhea). Exclusive breastfeeding means giving the baby breast milk only and nothing else.
During pregnancy, infancy, and childhood, recommended intakes of macronutrients and most micronutrients are higher relative to body size, compared with those during adulthood. In elderly persons, some nutrient needs (e.g. vitamin D) increases, while others (e.g. energy, iron) are reduced.
Micronutrient needs in adults 19 to 50 years of age differ slightly according to gender, e.g. menstruating females require more iron, compared with males of similar age.
Nutritional Requirements during Pregnancy and Breastfeeding
Pregnant and breastfeeding women have increased requirements for both macronutrients and micronutrients. Protein requirements in pregnancy rise to 1.1 g/kg/day (71 g), amounting to more than a 50% increase in protein intake to allow for fetal growth and milk production. Pregnant and/or lactating women also require increased amounts of vitamins A, C, E, and certain B vitamins including folate. Folate intake is especially important for the prevention of neural tube defects and should be consumed in adequate amounts prior to conception. Pregnant women also require increased amounts of calcium, iron and zinc.
Nutritional Requirements during Infancy and Early Childhood
Requirements for macronutrients and micronutrients are higher on a per–kilogram basis during infancy and childhood than at any other developmental stage. These needs are influenced by the rapid cell division occurring during growth, which requires protein, energy, and nutrients involved in DNA synthesis and metabolism of protein, calories, and fat. Increased needs for these nutrients are reflected in DRIs for these age groups, some of which are briefly discussed below.
The nutritional status of a woman before and during pregnancy has direct impact on the development and nutritional status of her baby. Malnutrition before and during pregnancy increases the risk of low birth weight and malnutrition during infancy. That’s why The Lancet 2008 Maternal and Child Nutrition Series identified the need to focus on the crucial period from conception to a child’s second birthday – the 1000 days in which good nutrition and healthy growth have lasting benefits throughout life2.
- Needs are so high that iron supplements are usually recommended
- The Lancet. Maternal and Child Nutrition Series 2013. http://www.thelancet.com/series/maternal-and-child-nutrition