So after a month of hitting 100%+ of the Australian/New Zealand "recommended dietary intake" guidelines, I figured it might be a good idea to actually research where they get these numbers from.
The first chapter of "NUTRIENT REFERENCEVALUES FOR AUSTRALIA AND NEW ZEALAND (2006)" was a warning about what I was about to discover; in a box summarising various definitions, I found something quite remarkable:
SDT: Suggested Dietary Target
A daily average intake from food and beverages for certain nutrients that may help in prevention of chronic disease.
RDI: Recommended Dietary Intake
The average daily dietary intake level that is sufficient to meet the nutrient requirements of nearly all (97-98 per cent) healthy individuals in a particular life stage and gender group.
But why the seperate definitions? Surely what the goverment would recommend is what they deem healthiest? Wrong. As it turns out, RDIs are calculated by finding the intake of the average person not showing deficiency symptoms plus two standard deviations (if that is not know then usually 20% is used). So we are being recommended just enough to get by.
In a societey where chronic disease and pain is so prolific do we really want to be setting our goals relative to what others eat? At some point in the past, with limited research, one could argue that average is the best we could hope for. But for years even the goverment has had separate suggestions for optimum nutrition. Here are some comparisons between the RDI and SDT for a few nutrients:
- Vitamin A: 900/1,500µg
- Vitamin C: 45/220mg
- Dietary Fiber: 30/38g
References and rationale are given in the document.
Keep in mind this is all coming from one document from 2006! Our understanding of optimum nutrition can only have improved.
It makes no sense to me that these agreed open values do not get publicised as much as RDIs. Seeing the difference in those examples show just how unhealthy we are as a species.