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
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!
book.
