That is a difficult question and I don't want to pretend to be an expert
on that. I just wanted to point out that the health benefits of
different foods can not be explained only by the traditional
micronutrients. However, I think that it is not so difficult to make an
approximate estimation about the phytochemical content based on the data
that you now have. I think that it is better to have an approximate
value than have none. The antioxidant capacity of many phytochemicals is
greater than vitamins and so it is important to take them in to account
even if it is not possible to be exact in it.

"I think that it is not so difficult to make an approximate
estimation about the phytochemical content based on the data that you
now have."

True, but meaningless. I see a heap of chemical numbers from your
references with no relationship whatsoever to human health. The
individual RDA's for beta-carotene, vitamins C & E, even though
antioxidants, are all based on criteria other than antioxidant
activity. I havn't found anywhere, so far, how to relate
antioxidant/(iso)flavonoid activity as such to human health.

That's the bottom line. Where can I find numbers to relate these,
even approximately, to human beings and our health?

John

Given the data, 60 mg/day seems to me a reasonable first stab at an
RDA for total flavonoids (halves CHD risk according to the SCS).
Unfortunately, the USDA excluded all total flavonoid measurements
even though that's all that seems to be justified by health studies
so far; there may be a lot of additional relevant data out there
somewhere. But, their work will be sound as far as it goes.

I'm inclined to not use the total antioxidant data of Halvorsen
et.al, mostly because the authors themselves intended it only as a
screening tool to guide further work. If I did use it, I believe I
have to subtract beta-carotene, ascorbic acid and alpha-tocopherol
(converted to mmol/100g) from total antioxidant then convert
remaining mmole/100g to mg/100g using quercetin (302 g/mole) as
reference.

Comments, Juhana?

"Okinawan elders get an average 100 mg flavonoids from diet"

But, the median of the SCS data is 20 mg/day; the maximum 71. Are you
really proposing that all of Europe is that deficient in their diet?
I thought 60 was pushing it!

Of course, the problem is almost certainly what is defined as a
flavonoid - I gather from Kumpulainen that this has been
exceptionally variable e.g. the two SCS graph points for Finland are
about 3 and 6 mg/d, yet K. finds 55 mg/d in Finland for the total of
17 specific flavonoids, and 124 when other groups are included.

The ideal for me of course is to locate the data used by the authors
contributing to the graph I'm using to relate numbers to human
health. That's key - to use numbers I can relate to human beings.

Any suggestions as to where I can locate the SCS reference data, or
something that can be converted to it?

John