Learning objectives

Figure 1. 1 The concept of balance Figure 1.1 The concept of balance. The demands for nutrients comprise metabolic and physiological processes that utilize nutrients. Supply is determined by intakes of food, availability of nutrient stores, and de novo production of nutrients.

Table 1.1 The acute phase inflammatory response to trauma or infection

Table 1.2 The metabolic response to injury and infection increases requirements for energy and protein

Figure 1. 2 The association between nutrition and health Figure 1.2 The association between nutrition and health. The requirements of the body for nutrients will be met by a broad range of intakes. Very low and very high intakes of any nutrient will be associated with ill health. The transition from intakes that are meeting demands and at which risk of disease is low to intakes that would be associated with disease is not abrupt.

Table 1.3 The three stages of iron deficiency

Research Highlight 1 Strategies for combating vitamin A deficiency (VAD)

Figure 1. 3 Determining nutrient requirements using the balance method Figure 1.3 Determining nutrient requirements using the balance method. Precise measurements of nutrient intake and of output by all possible routes enable determination of nutrient requirements. The highest level of intake at which balance can no longer be Maintained will indicate the actual requirement of an individual for that nutrient.

Table 1.4 Anthropometric measures used to estimate body composition and nutritional status

Figure 1. 4 Availability of animal and plant protein by world region Figure 1.4 Availability of animal and plant protein by world region. Per capita availability of protein from plant and animal sources calculated from the 2004 FAO global food balance sheets.

Figure 1.5 The association between risk of nutrition-related risk and level of nutrient intake. EAR, estimated average requirement; RNI, reference nutrient intake; UL, tolerable upper limit.

Figure 1. 6 The normal distribution as a basis for DRVs Figure 1.6 The normal distribution as a basis for DRVs. UK DRVs are based upon an assumed normal distribution of individuals’ nutrient requirements and level of nutrient intake. The EAR (estimated average requirement) is set at the center (mean) of the distribution. LRNI (lower reference nutrient intake) and RNI (reference nutrient intake) values are placed 2 standard deviations below and above the mean, respectively. The nutrient requirements of all but 5% of the population should therefore be met by levels of intake between these two values.

Table 1.5 Definitions of DRV terms used in the UK, North America, and Oceania

Summary Box 1

Self-Assessment Questions