nutrient-density of modern plant breeds

[Guest guest]

http://www.scienceblog.com/community/article4811.html

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A recent study of 43 garden crops led by a University of Texas at

Austin biochemist suggests that their nutrient value has declined in

recent decades while farmers have been planting crops designed to

improve other traits. The study was designed to investigate the

effects of modern agricultural methods on the nutrient content of

foods. The researchers chose garden crops, mostly vegetables, but also

melons and strawberries, for which nutritional data were available

from both 1950 and 1999 and compared them both individually and as a

group.

From University of Texas Austin:

Study suggests nutrient decline in garden crops over past 50 years

A recent study of 43 garden crops led by a University of Texas at

Austin biochemist suggests that their nutrient value has declined in

recent decades while farmers have been planting crops designed to

improve other traits.

The study was designed to investigate the effects of modern

agricultural methods on the nutrient content of foods. The researchers

chose garden crops, mostly vegetables, but also melons and

strawberries, for which nutritional data were available from both 1950

and 1999 and compared them both individually and as a group.

The study, based on U.S. Department of Agriculture data, will appear

in the December issue of the Journal of the American College of

Nutrition. Its lead author is Dr. of the university's

Biochemical Institute in the Department of Chemistry and Biochemistry.

His coauthors are Drs. Melvin Epp and Hugh Riordan of the

Bio-Communications Research Institute in Wichita, Kan., where is

a research consultant.

According to , establishing meaningful changes in nutrient

content over a 50-year time interval was a significant challenge. The

researchers had to compensate for variations in moisture content that

affect nutrient measurements, and could not rule out the possibility

that changes in analytical techniques may have affected results for

some nutrients.

''It is much more reliable to look at average changes in the group

rather than in individual foods, due to uncertainties in the 1950 and

1999 values,'' said. ''Considered as a group, we found that six

out of 13 nutrients showed apparently reliable declines between 1950

and 1999.''

These nutrients included protein, calcium, phosphorus, iron,

riboflavin and ascorbic acid. The declines, which ranged from 6

percent for protein to 38 percent for riboflavin, raise significant

questions about how modern agriculture practices are affecting food

crops.

''We conclude that the most likely explanation was changes in

cultivated varieties used today compared to 50 years ago,''

said. ''During those 50 years, there have been intensive efforts to

breed new varieties that have greater yield, or resistance to pests,

or adaptability to different climates. But the dominant effort is for

higher yields. Emerging evidence suggests that when you select for

yield, crops grow bigger and faster, but they don't necessarily have

the ability to make or uptake nutrients at the same, faster rate.''

According to , these results suggest a need for research into

other important nutrients and foods that provide significant dietary

calories, such as grains, legumes, meat, milk and eggs.

''Perhaps more worrisome would be declines in nutrients we could not

study because they were not reported in 1950 -- magnesium, zinc,

vitamin B-6, vitamin E and dietary fiber, not to mention

phytochemicals,'' said. ''I hope our paper will encourage

additional studies in which old and new crop varieties are studied

side-by-side and measured by modern methods.''

[Guest guest]

Mike-

>> said. ''I hope our paper will encourage

>>additional studies in which old and new crop varieties are studied

>>side-by-side and measured by modern methods.''

Interesting enough, though it's nothing new, but they seem to be missing at

least half the point: that sort of experiment will completely fail to

account for differences in soil fertility.

-

[Guest guest]

At 10:26 AM 12/3/04 -0500, you wrote:

>Interesting enough, though it's nothing new, but they seem to be missing at

>least half the point: that sort of experiment will completely fail to

>account for differences in soil fertility.

Exactly. I heard a short piece on the radio this morning about this.

After the teaser about the upcoming segment, I EXPECTED it to be about soil

fertility. But 'twas not to be.

MFJ

Why not ... [all sorts of things]? ~ Anton

[Guest guest]

>Mike-

>

>>> said. ''I hope our paper will encourage

>>>additional studies in which old and new crop varieties are studied

>>>side-by-side and measured by modern methods.''

>

>Interesting enough, though it's nothing new, but they seem to be missing at

>least half the point: that sort of experiment will completely fail to

>account for differences in soil fertility.

-Al Kapuler, founder of Seeds of Change, currently

owner/operator of Peace Seeds has written extensively about the

difference in nutritional value of the various cultivars. If you are

interested, get his publication " Free Amino Acids in Our Commonly

Grown Organic Fruits and vegetables, Particulary the Ones that Make

Proteins "

You will find plenty of studies of plants grown in the same soils

where one cultivar is outrageously more nutritious than others. And,

you'll find info about cultivars that provide certain array's of

nutrients that are more appropriate for certain types of human

activiteis: mental work, heavy lifting, etc.

You can contact Dr Kapuler at 2395 SE St, Corvalis OR. Price

of the pub, with postage, is $20.

Kapuler focuses on free amino acids because he feels that they are a

better indicator of nutritional value than assays of vitamin's and

minerals are. He is very strong on the idea that free amino acids

work in harmony with vitamins and minerals in a meal to build high

quality proteins for the human bodies while 'complete' proteins taken

in at a meal do not interact with the vitamins and minerals taken in

at that meal. This leads to inefficient usage of nutrients consumed.

The market place farms, of course, have cultivars selected for yield

and shipping tolerance. There is little or know concern for

nutritional content. When there appears to be concern (Golden Rice),

it's generally really marketing that's happening and the artificial

plant (hybrid) most likely will not be utilized by the human body

even to the degree claimed, as it is too 'new.'

All of this is an important aspect of nutrient density that's either

over looked...or denied.

-Allan