This is a diary about diet. Not the New Years diet currently underway due to the huge amount of Christmas cakes and puddings I ate during December, but diet in general. Disclosure: I am neither an agronomist nor nutritionist, so this is written from the perspective of an interested consumer. I like to cook, and am interested in both the physical and nutritional properties of the ingredients and how they work so I can be a good cook. I am also convinced that a good balanced diet is the easiest way to lose weight and stay healthy. However, unless one has access to farmers’ markets or really good grocery stores, this can sometimes be difficult. Below the fold, it becomes apparent just how difficult.
Almost any old timer will complain that newer varieties of fruit and vegetables, while more attractive, have much less flavor than they used to. Like many others here at Kos, I figured that intensive farming using chemical fertilizer was the major culprit and that buying organic was one way of providing a healthy diet. From the Organic Center website:
Higher yields have been made possible by the combination of new plant varieties, and increasing reliance on fertilizer, pesticides, irrigation, and For example, there have been double- digit percentage declines of iron,
calcium, selenium and other vital nutrients in many contemporary, high-yield crops compared to older varieties and/or lower-yielding fields. In general, the higher the yield of wheat, corn and soybeans, the lower the protein and oil content. High tomato yields come with lower levels of vitamin C and the cancer-fighting compounds lycopene and betacarotene. The effort of farmers, and agribusiness has been on increasing yields, not on food nutritional quality.
I thought I was getting around this by having access to organic products, even organic flour. However friends of mine here in the UK, many of whom use strictly organic ingredients, complain that the flour that they use now won’t work in older recipes. This made me think that perhaps there might be some other agent besides fertilizer and pesticides at work. The protein content of flour is what causes bread flour and pastry flour to have entirely different characteristics, so I wondered whether the properties of flour had changed over time.
Therefore, this paragraph , buried in the depths of an article on Australian megafauna in the January 4th Independent was interesting, and caused me to wonder if people as well as koalas were feeling negative effects of increasing CO2 in their diet.
While not officially endangered, koalas are at risk through loss of habitat, while increased levels of carbon dioxide in the atmosphere are reducing nutrients in eucalyptus leaves, their sole food source.
There have been conflicting stories in the popular press over whether increased CO2 will benefit humanity through increasing crop yields. It seems a logical conclusion that, since plants use it to grow, more CO2 would produce more growth and therefore better yields, and actually this seems to be true. There have been a number of experiments done over the last decade or so by a government program called FACE growing various plants in as natural an environment as possible while elevating CO2. One of the research facilities who received a FACE grant, The Center for Carbon Dioxide Study and Global Change had this to say:
In conclusion, the results of these several FACE experiments clearly indicate that as the air's CO2 concentration continues to rise, wheat plants will likely fare considerably better under both normal and droughty conditions and high and low soil nitrogen conditions than they do currently. Consequently, with the human population of the earth continuing to increase, we would be wise to think very carefully about limiting anthropogenic CO2 emissions that could do so much to alleviate hunger and its many negative consequences. To spurn the hand of providence in providing this unsought blessing, which is also a boon to the natural environment, is a dangerous thing indeed, for it could well place us in the position of operating in opposition to both moral and logical mandates, the devastating consequences of which may be nigh unforgivable.
This is a position that is often expressed in the media, but the whiff of fundamentalist theology was intriguing so I Googled the name of the chairman, Craig Idso, and found that:
From 2001-2002, C. Idso served as Director of Environmental Science at Peabody Energy in St. Louis, MO. According to a newsletter from Basin Electric, a Western Fuels Association member company, Craig and Keith Idso produced a report, "The Greening of Planet Earth: Its Progression from Hypothesis to Theory," in January 1998 for the Western Fuels Association. Western Fuels Association is the suspected funder of the Center, though there is nothing more than circumstantial evidence. The Center does not reveal its funding sources.
It’s not a necessarily a smoking gun because FACE is run out of The Department of Energy, which is suspicious in and of itself, but never mind.
However, most other researchers get into more detail, as in this Nature (subscription only) article the conclusion of which is:
The scientists covered certain areas of a wheat field under a green house and enhanced the content of CO2 to 550 ppm. It is believed that in 50 years earth athmosphere will have a CO2-content like that. Recently it is around 380 ppm. Although carbon dioxide obviously works as fertilizer (the plants can use more CO2 for an improved photosynthesis) the scientists found simultaneously a protein content which was 20% lower than normally in the plants which grew under the artificial greenhouse effect.
This might partially explain my friends' flour problem. In addition, degradation due to increased CO2 levels in both protein and micronutrient levels have been found in potatoes, and soybeans as well. Ironically the starch content increases which makes for delicious fluffy french fries. However, you have to eat proportionately more of them to get the same nutritional content. “Would you like a large order of fries with that?” From the article on soybeans:
Although plant biomass may increase in response to higher concentrations of atmospheric CO2 , that mass may have a modified chemical composition. Carbohydrate content is likely to increase disproportionately with respect to nitrogenous compounds. Pest species could respond to this change by eating more plant. Soybean looper (Pseudoplusia includens ) larvae fed soybean foliage grown at 650 ppmv CO2 consumed 80 percent more than did larvae fed on leaves grown at 350 ppmv CO2 .
This brings me to a final and perhaps overreaching point: perhaps the obesity epidemic has multiple causes. Along with a more sedentary lifestyle and access to richer food, we might be overeating to get the levels of nutrients that we formerly could get with smaller portions. This is no excuse for consuming vast quatities of Christmas goodies, and granted that humans are not soybean loopers (we hopefully have more brains than that), but it would be interesting to see a graph comparing the global obesity epidemic with elevated atmospheric CO2. In the meantime a good multivitamin/ mineral supplement wouldn’t hurt.