small fish Ca datum

[Guest guest]

The abstract for the following article already passed through this

list a few weeks ago in the dried shrimp thread, but I just got a

copy of the full-text and extracted a datum on Ca content (mundane,

yet annoyingly difficult-to-obtain information).

Hansen M, Thilsted SH, Sandstrom B, Kongsbak K, Larsen T, Jensen M,

Sorensen SS. Calcium absorption from small soft-boned fish. J Trace

Elem Med Biol. 1998 Nov;12(3):148-54.

For mola (sp. Amblypharyngodon mola) from Bangladesh (which is

described as " small and soft-boned " but no more specific info about

size is given) the Ca content is 11.5mg/cal [11.7mg/g] of fresh

fish. (For what it's worth, they state 6.28g of freeze-dried mola

corresponds to 24g of the fish fresh; I don't how how that relates to

the form of dried fish we buy in the stores. More mundane, yet

annoyingly difficult-to-obtain information...)

The purpose of the study was to compare Ca absorption for the fish to

milk, and the results show the Ca from the fish is absorbed at about

the same rate as milk, both in the 20-25% range. [i pasted the

abstract again below.]

Using USDA data for milk, we have that 3.25% " whole milk " has

2.0mg/cal [1.2mg/g] and skim milk has 3.5mg/cal [1.2mg/g].

Therefore, small mola has about 5.8 [3.3] times more Ca per calorie

than whole [skim] milk. To put that in perspective, you would only

need to eat about 25g (less than one ounce) of fresh small mola to

get the same amount as Ca (290mg) in one cup of milk, and the

absorption would be about the same.

Looking at these numbers, it seems likely that a cup of baechu-kimchi

made with a typical recipe including some small fish and/or small

shrimp would have a little more Ca than a cup of milk, especially

considering the Ca contribution of brassicas.

Also note that fish are good sources of Zn, Fe and vit A.

All this useful to know, but as I've said in the past, Ca is easy to

get; worry about Mg and other stuff.

Mike

SE Pennsylvania

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The prevalence of osteoporosis in developing countries is low

compared to most industrialised countries despite an apparent low Ca

intake. It is possible, however, that food surveys have overlooked

important Ca sources in developing countries. Small fish eaten with

the bones can be a rich source of Ca, even though Ca from bone may be

considered unavailable for absorption. In the present study,

absorption of Ca from indigenous Bengali small fish was compared with

the Ca absorption from milk. Ca absorption from single meals was

determined in 19 healthy men and women (21-28 y). Each subject

received two meal types on two separate occasions. Both meals

consisted of white wheat bread, butter and ultra pure water with the

main Ca source being either small Bengali fish (397 mg Ca in total)

or skimmed milk (377 mg Ca in total). The meals were extrinsically

labelled with 47Ca, and whole-body retention was measured on day 8,

12, 15 and 19 after intake of each meal. The labelling procedure was

evaluated by an in vitro method. The calculated absorption of Ca as

measured with 47Ca whole-body retention was 23.8 +/- 5.6% from the

fish meal and 21.8 +/- 6.1% from the milk meal (mean +/- SD), which

was not significantly different (p = 0.52). Even after correction for

an incomplete isotope exchange, as indicated by the in vitro study,

Ca absorption was similar from the two meal types. It was concluded

that Ca absorption from small Bengali fish was comparable that from

skimmed milk, and that these fish may represent a good source of Ca.

PMID: 9857327 [PubMed - indexed for MEDLINE]

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[Guest guest]

>All this useful to know, but as I've said in the past, Ca is easy to

>get; worry about Mg and other stuff.

>

>Mike

OK, so what is the *Mg* content of mola? Or dried shrimp?

Seems like nuts, greens, and fish are all good sources

of Mg too -- kimchi often has nuts and always has greens.

Though maybe the darker green stuff should be added

to the pale Napa ...

-- Heidi