Signs of Nutrient Decline
Here's summary of the evidence that nutrients in non-organic factory-farm foods are declining:
Many vegetables appear to contain lower levels of vitamins and minerals today than they did in 1975, according to official USDA nutrient data reviewed by health writer Alex Jack. Jack has reported that a random sample of USDA data on a dozen vegetables showed that calcium has fallen an average of 26.5 percent, vitamins A and C have dropped 21.4 percent and 29.9 percent, and iron has plummeted by an average of 36.5 percent.
The concentrations of eight essential minerals in 20 fruits and 20 vegetables in Great Britain has declined, and water content has increased in fruits over the last 50 years, according to a paper by Anne-Marie Mayer in the British Food Journal (1997, Vol. 99, No. 6). She found that average calcium content had dropped 19 percent, iron was down 22 percent and potassium declined 14 percent for the 20 vegetables studied.
Fruits and vegetables grown using synthetic chemical nitrogen may contain an average of 20 percent less dry matter and more water compared to organic crops fertilized with slower-release natural sources of nitrogen. Higher water content means lower nutrient concentrations per pound of produce (and weaker flavors).
Meat and dairy products from animals raised in feedlots or cages on high-grain diets contain lower levels of nutrients than meat from animals that are raised on their natural diet of grass, or, in the case of poultry, grass and grain.
According to the USDA’s Nutrient Database, factory-farm eggs contain 20 percent less iron and 59 percent less vitamin A than they did in 1975. The USDA data also show that today’s eggs contain 3 percent more water than in 1975.
These factory-farm eggs contain significantly less health-enhancing carotenes than eggs from pasture-raised chickens. This difference is easy to see because the more carotenes, the more orange in color the yolks are. Factory-farm eggs also are lower in vitamin E, vitamin B-12, vitamin A, folic acid and omega-3 fatty acids, according to a remarkable collection of studies assembled by journalist Jo Robinson on her Web site. Robinson also documents that not only do factory-farm eggs contain less vitamins, they have more fat and cholesterol than eggs from pastured poultry.
And last but certainly not least, there is this: Because of the last few centuries of human industrialization across the globe, today’s atmosphere contains 30 percent more carbon dioxide than it did during the millions of years that plants, animals and humans have been evolving together. And the CO2 levels are predicted to increase even more unless/until we reduce our CO2 emissions. CO2 is the basic building block for photosynthesis; when plants are exposed to higher levels of CO2, they produce a higher proportion of carbohydrates than normal and this may lead to reduced levels of other nutrients, per calorie. A startling literature review published in Trends in Ecology and Evolution (2002, Vol 17, No. 10), reported initial studies have found that the concentration of every measured element except potassium declined when wheat was grown at high levels of CO2 , and four out of five elements in brown rice declined. Global CO2 levels are predicted to continue to increase, and this could be yet another factor that is damaging the quality of our food.