Tuesday, October 12, 2010

Heirloom Vegetables Are Better For You

Awhile back, we wrote about the nutritional benefits of growing heirloom tomatoes, citing a study from the University of Texas, showing that supermarket tomatoes have dropped in nutritional value since 1950. 

“We conclude that the most likely explanation was changes in cultivated varieties used today compared to 50 years ago,” Dr. Donald Davis, the leader of that study reported. “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.”
 
That report from the University of Texas also showed a precipitous drop in the nutritional value of other vegetables. The full study printed in the December 2004 issue of the "Journal of the American College of Nutrition" says that hybrid varieties of fall/winter garden favorites such as broccoli (vegetable #5 in Table 2 of that study), cabbage (#7), cauliflower (#11), chard (#13), kale (#20), lettuce (#22), peas (#28) and spinach (#35) have current nutritional shortcomings, compared to 50 years ago. 

The study compared calories, protein, carbohydrates, calcium, phosphorus, iron, Vitamin A, Thiamin, Riboflavin, Niacin, Ascorbic Acid and other nutrients. In just about every case, the 1950's version of supermarket veggies was better for you than the 1999 selection.

Using broccoli as an example, the 1950 crop had nutritional advantages over the 1999 broccoli in the following categories (measured in grams or milligrams, unless stated otherwise) per 100 grams of edible portion:

Protein: 3.3 (1950) to 2.9 (1999)
Carbohydrates: 5.5 to 5.2
Calcium: 130 to 48
Phosphorus: 76 to 66
Iron: 1.3 to .88
Vitamin A (IU): 3500 to 1542
Thiamin: .1 to .06
Riboflavin: .2 to .1
Niacin: 1.1 to .6
Ascorbic Acid: 118 to 93

What else is different between supermarket vegetables grown in 1950 and vegetables grown today, besides the introduction of nutrient-sapping hybrid varieties?

The farm itself and the methods used to grow the food, including the increasing use of inorganic chemical fertilizers and pesticides to increase yields.

As a youth, I spent summers at the family farm outside Wibaux, Montana. Grandpa, Grandma and Uncle Hubert ran the "operation" (which was comprised of Hubert's two children, his wife Minnie, and cousin Gary). Fertilizer for the vegetables grown there came out of the back end of horses, cows, sheep and pigs. "Use every part of the pig except the oink," Uncle Hubert was fond of saying. 

Seeds were saved at the end of each growing season from the current year's crop. The family was too poor to afford expensive pesticides, so Grandma headed out to the vegetables each morning to spray the aphids off with water from the hoses that ringed the acreage. 

They were organic, or nearly organic, out of necessity. Several times each week, Hubert would truck the vegetables into town to the local market.

Now, that 160-acre farm is out of the family's hands and has been combined with several other local farms and is run by a conglomerate.

Bottom line: if you want to feed your family the most nutritious (and safe) vegetables, grow them yourself, using heirloom varieties and growing them as organically as possible. 

Second best option: buy your vegetables at a farmer's market. Here in Northern California, there is no shortage of farmer's markets, nor a shortage of farmers selling organically produced heirloom vegetables.

Among the online seed catalogs specializing in heirloom vegetable seeds:

There are plenty more sources for heirloom seeds. Mention your favorite!

7 comments:

  1. Thank you for the valuable resource.

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  2. Well, I know they look better, and most certainly taste better. Stands to reason that they would be better for you, if for no other reason than those who grow them care more about what goes into them !

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  3. PS - Don't forget the physical and mental benefits of gardening.

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  4. I recently gave a couple of Black Krim tomatoes to a friend who had never eaten anything but the supermarket hybrids. She loved them so much, she's now planning a garden of her own for next year.

    I can believe that the hybrids of the last 50 years are less nutritional. After all, if something has no taste and a long shelf life, it stands to reason that it's probably not as good for you.

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  5. The UT study compared commercially grown tomatoes of 1950 to commercially grown tomatoes of 1999. Tomato varieties chosen by agriculture for supermarkets are varieties that are bred not so much for taste but their ability to withstand bruising during shipping, look pretty and maintain their firmness, varieties such as Sunbrite, QualiT 21, Merced, Sonnet. These are varieties that you would not choose as a home gardener.
    I would like to see a study comparing the nutritional value of the top 10 hybrid tomatoes grown in home gardens with the nutrition of the top 10 heirloom varieties.

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  6. How viable are the seeds from the heirloom tomatoes you get from the store? We have saved some from last year and I wanted to try my hand at planting some this year. Are they true heirlooms or are they hybrids too? I just want to find out before I plant. Thank You!

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  7. Susan, if you stored those tomato seeds properly, they should be viable for 5 to 7 years. More info about seed storing here: http://farmerfredrant.blogspot.com/2010/08/tomato-and-pepper-seed-saving-tips.html

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