Study: Nutrition concerns and health effects of veg. diets

[JP]

Nutrition concerns and health effects of vegetarian diets.

http://www.ncbi.nlm.nih.gov/pubmed/21139125

admits a lot of benefits, though still a lot of confusion (in my opinion) regarding correlation vs causation, but its still good stuff

[Gelert]

Did you manage to have a look at the full article JP? It's a review so it obviously integrates data from a range of primary sources, but it seems that a lot of the conclusions are drawn from one reference (reference 6) which is cited quite often when a big comment is made and is the source for Table 1, which lists the mean values for nutrients such as iron, zinc, B12, vitamin D etc. in vegans, lacto ovos and non-vegetarians in comparison to DRI values. It seems that vegans do really well on iron, OK on omega 3s but embarrassingly low on B12 and vitamin D. Not really rocket surgery, but a key thing is the third or fourth column along, listing n. Values in the range of 4-10 individuals are given, but it's unclear whether say, an n=10 means 10 individuals in total, or 10 vegans, 10 LOs, 10 non-veggies in the study since only the value is quoted for the nutrient rather than each group for each nutrient. But either way the sample sizes are very small and only the mean is given and not the standard deviation or error, so the spread could be massive. In other words, you could have the conclusion for vitamin B12 where there are three happy supplementing vegans with normal-ish values totally skewed by one person who is content to obtain their B12 from watching beautiful sunrises and you'd not know. Even at the small group/study size it's amenable for some statistical testing for significance, but that is not reported.

This is more a criticism of the primary study in question rather than this review, but seeing as it's fairly key to the author's argument it does rather make it seem like someone is trying to paint strokes much larger than their brush.

[JP]

good points.

Funny thing about these studies is also the lack of regional variety. Us vegans seem to be a very globally homogenous group in the eyes of nutrition science

Its not like they would just take 100 japanese and judge the nutritional breakdown of meat eaters from that and assert that its a globally valid study. But with vegans it seems like they dont really pay much attention to the varieties.

But from my personal point of view the diet of finnish vegans is greatly different from the ones in UK - and I presume more variations in other countries too. Now that would be an interesting study, comparing the structure and quality of vegan diets in different countries - only a matter of time before someone does that!

[Gelert]

^
Top point.

Something for Dr. Vinnari to consider perhaps as a slight diversion? (He's Finnish, there's only 5.4m of you so you must know him!)

viewtopic.php?f=13&t=21914

[Clem Snide]

[quote="JP"]
But from my personal point of view the diet of finnish vegans is greatly different from the ones in UK

[beforewisdom]

[quote="JP"]
But from my personal point of view the diet of finnish vegans

[beforewisdom]

[quote="JP"]good points.

Funny thing about these studies is also the lack of regional variety. Us vegans seem to be a very globally homogenous group in the eyes of nutrition science

Its not like they would just take 100 japanese and judge the nutritional breakdown of meat eaters from that and assert that its a globally valid study.

[JP]

this is all of course anecdotal, but already cultural variations of foods make a big impact of what vegans there would eat.

Like in finland the vegans i know would eat way more rye bread, rapeseed oil based margarines, use rapeseed instead of olive oil or sunflower oil in cooking, root vegetables, soya mince/tvp products, porridge than brittish vegans.

I think regional variations would come out in studies even if internally in any country they would have big variation among vegans like you mentioned.

Perhaps when on web boards people mostly talk about vegan specialist products rather than everyday foods they have grown up with even as a non vegan, like rye bread and rapeseed oil based margarines in finland as an example?

and gelert, yes i know him, and i think he is a (non posting) member on VF - he used to be a bench press champion

[Gelert]

[quote="JP"]and gelert, yes i know him, and i think he is a (non posting) member on VF - he used to be a bench press champion