Where an RDI for a nutrient has not yet been formulated, a 'safe and adequate' range can generally be advised. In fact, some nutritionists think that a range rather than a specific amount should be stated for all RDIs.

It is difficult to apply RDIs to an individual because what really needs to be known is that individual's particular requirements for the nutrients in question. However, if your average daily intake of any nutrient is less than two-thirds of the RDI, or is below the lower end of the 'safe and adequate' range, then you may not be getting enough of an essential nutrient.

Sometimes this may be due to not eating enough food or alternatively it may be due to poor food choice.

In these few pages, you will find tables listing the general recommended dietary intakes. Differences in recommendations between countries are, by and large, of no real consequence and reflect slightly different views of scientific evidence or local differences in food supply and nutritional needs. In the latter part of this book RDIs for individual nutrients are also shown in the Food Charts.