• The British Journal of Nutrition has a very good Supplement on The Nutritional Needs of Children
• BJN 2007, vol 92, pp S 67-S 232 Editors Koletko B, et al
• In deciding how much should of a nutrient be recommended it is important to define Nutrient Handling.
• This is an interesting concept and identifies the different variables when food and its constituents are eaten.
• 1. Dietary intake (of foods or nutrient mixtures); impact of processing and preparation.
• 2. Milieu within the gastrointestinal tract (matrix effects, intraluminal nutrient interactions, gut transit time).
• 3. Mucosal binding.
• 4. Mucosal cell uptake.
• 5. Mucosal export (portal circulation or mesenteric lymphatic transport).
■ 6. Hepatic uptake.
• 7. Organ (including liver) clearance.
• 8. Biliary clearance and excretion.
• 9. Systemic circulation and peripheral distribution.
• 10. Renal clearance and excretion.
• 11. Peripheral tissue utilisation (e.g. metabolic/catabolic use. structural roles) and deposition.
Each nutrient can then be individually assigned one or more of these key steps as being rate-limiting for its utilisation.
Another variable will be age as these variable will be different at different ages of development.
However I was very interest ed to note that a very important variable the speed and length of time spent eating was not mentioned. This is an enormous variable and very neglected, by all but the traditional French eaters.
- Martin Eastwood