By Kip Hansen – Re-Blogged From WUWT
Note: This is Part 2 of a four part series. If you are not familiar with The Fight Against Global Greening – Part 1, you can either read it in its entirety and then read this, or read the introduction of Part 1 up to the line “Let’s look at #1” and then read this. — kh
Carl Zimmer of the NY Times has said “‘Global Greening’ Sounds Good. In the Long Run, It’s Terrible.”. In collaboration with Dr. J. E. Campbell of the Sierra Nevada Research Institute, he has stated that position, offering us these:
Bad Things About Global Greening: (quoted from Zimmer’s article)
1. “More Photosynthesis Doesn’t Mean More Food“
2. “Extra Carbon Dioxide Can Make Plants Less Nutritious”
3. “More Plants Won’t Prevent Climate Change”
4. “Global Greening Won’t Last Forever”
In Part 1, we looked at the question of the relationship between increased photosynthesis and food production (Zimmer’s #1). Now….
Let’s Look at #2: “Extra Carbon Dioxide Can Make Plants Less Nutritious”
Here’s what Zimmer and Campbell say:
“A number of studies indicate that plants that grow in extra carbon dioxide often end up containing lower concentrations of nutrients such as nitrogen, copper and potassium.”
As more carbon dioxide gets into the atmosphere, the problem will grow. “There’s definitely strong evidence that quality will be affected,” said Dr. Campbell.
It’s not clear why this happens. In a paper published in the journal Current Opinion in Plant Biology in June, Johan Uddling of the University of Gothenburg in Sweden and his colleagues speculated that microbes are to blame.
Just as carbon dioxide speeds up photosynthesis, it may also increase the rate at which soil microbes take up nutrients, leaving less for plants to suck in through their roots.”
If we eat food that lacks nutrients, we become more vulnerable to a host of diseases. Recently, a team of researchers at Stanford University studied how future changes to crops could affect the world’s health. The findings were grim. In Southeast Asia, for example, the researchers estimated that the rate of iron deficiency may rise from 21.8 percent to 27.9 percent by 2050. Deficiencies in iron and other nutrients could make millions of people more vulnerable to diseases including malaria and pneumonia, leading to many premature deaths.”
Getting rid of the silly part first: “microbes are to blame” — Uddling et al. state very plainly that they have no idea why the differences in (primarily) proteins are found in wheat grown under higher CO2 concentrations. Quoting from the conclusion: “At present, none of mechanisms and processes hypothesized can fully explain the CO2-induced declines in crop N [proteins] concentrations.” Second silly part: “If we eat food that lacks nutrients”…. If it has no nutrients, it is not food at all. Every bite of food we eat has either more, the same, or less of any one “nutrient” than every other bite of food — every piece of piece of fruit has more or less nutrients than every other piece of fruit — every grain has different concentrations of nutrients than every other grain. That there are differences in concentrations of nutrients in foods is not a cause for alarm nor does it “cause” diseases, disabilities, or vulnerabilities. I will reveal the true causes further on.
The most important point is embodied in the claim that plants grown under enhanced CO2 conditions “often end up containing lower concentrations of nutrients such as nitrogen, copper and potassium.” This is the food faddists fallacy and is responsible for a great deal of nonsense in the food and nutrition fields of science.
There are always differences in nutritional values between individual crops of any food item. The same food item harvested from the south forty acres of my grandfather’s farm will have different nutritional qualities when compared to the same variety harvested off the north forty acres of the same farm. This is due to the slightly differing growth conditions, water availability, soil nutrient levels, fertilization schedules, planting dates, maturity at harvest and handling of the crop after harvest. The south forty crop may have discernibly higher percentages of certain minerals, proteins, and carbohydrates than the north forty crop. Likewise, the north forty crop may be higher in other measures of “nutritional value”.
When a farmer grows a different variety of the same crop — say a different corn variety — then the game changes wildly.
For instance, there are currently preserved at The Crop Trust 29,401 different varieties of maize (corn to those in the United States). Here’s an example of the effect on nutritional values of crop varieties of corn:
“Maize is the preferred staple food of more than 1.2 billion people in Sub-Saharan Africa and Latin America. However, maize-based diets, particularly those of the very poor, often lack essential vitamins and minerals. Over 50 million people in these regions are vitamin A deficient, which can lead to visual impairments, blindness and increased child mortality. The white maize eaten in much of sub-Saharan Africa contains almost no pro-vitamin A, while standard yellow maize varieties contain about 2 micrograms per gram (µg/g) – still insufficient in a diet dominated by maize. …. Scientists anticipate producing materials with the ultimate target of 15 µg/g within the next four years by using cutting edge lab tools to help select the best materials for breeding.”
Some maize contains no pro-Vitamin A at all — another yellow variety contains some, but not enough to prevent Vitamin A deficiency alone. Through cross-breeding maize varieties, the breeders at The Crop Trust hope to create a variety that will provide the 15 ug/g necessary to prevent Vitamin A deficiency in those for whom maize the major staple food. We all know the story of Golden Rice — suppressed by Greenpeace and other misguided fanatics — which could eliminate Vitamin A deficiency in areas depending on rice as a staple.
In this case, the corn that is the basic food for these people has virtually no Vitamin A — another variety has a lot more — but that “a lot more” doesn’t change the public health issue, it isn’t enough to guarantee to prevent Vitamin A deficiency. So the yellow corn is not a superfood despite having many multiples “more” Vitamin A. These two varieties are both insufficient…a change of plus or minus 10% or even 50% will make no difference. Vitamin A will have to be provided by a custom-bred corn variety or from another source.
“Fruits, roots, tubers, and leafy vegetables are the main providers of provitamin A carotenoids. Because of their availability and affordability, green leafy vegetables are consumed largely by the poor populations, but their provitamin A activity has been proven to be less than previously assumed. Among fruits, mangoes constitute an important seasonal source of vitamin A. Yellow or orange sweet potatoes are rich in provitamin A. Red palm oil has a high concentration of provitamin A carotenoids (500–700 ppm/100 g). Extension of new varieties with a high content of bioavailable provitamin A and locally adapted education and counseling on the handling and storage of provitamin A sources can significantly increase the vitamin A intake of vulnerable people.”
The converse can be true as well. In the Dominican Republic, where I served as a Humanitarian Missionary for many years, we never had to worry about Vitamin C deficiency among the poor. The fruits that grew wild in abundance provided all the Vitamin C anyone could need. More or less Vitamin C in the local variety of mango makes no difference — any single mango provides many times the daily requirement of Vitamin C and Vitamin A as well. But the babies of the poverty stricken desperately needed Vitamin A supplementation — because babies don’t eat mangoes.
This is true generally, all over the world. The small incremental differences in trace nutrients between crop varieties and between the same varieties grown in different locations is already greater than the differences seen between crops grown at various levels of atmospheric CO2. All of this was hashed out years and years ago when the latest “scary health story” was that “modern agriculture has depleted our soils so much that food is no longer nutritious.” (Usually followed by an advertisement for vitamin and mineral supplements that far exceed the needs of any human being anywhere).
For a full and exhaustive treatment of this issue, see Mineral nutrient composition of vegetables, fruits and grains: The context of reports of apparent historical declines [pdf] by Robin J. Marles (Health Canada).
The issue is nutshelled in this quote from the Marles study:
“Contemporaneous analyses of modern versus old crop varieties grown side-by-side, and archived samples, show lower mineral concentrations in varieties bred for higher yields where increased carbohydrate is not accompanied by proportional increases in minerals – a “dilution effect”.”
When modern crops produce more grain or fruit, through plant breeding, better agricultural methods, modern fertilizers and CO2 fertilization, the increased “food” doesn’t contain an equal, proportional, increase in minerals, vitamins, proteins and carbohydrates. Present day biology is not sure why this is.
The Bottom Line important for us from this paper is:
“The benefits of increased yield to supply food for expanding populations outweigh small nutrient dilution effects addressed by eating the recommended daily servings of vegetables, fruits and whole grains.”
Nutritional deficiencies don’t result from eating foods that “lack nutrients” — nutritional deficiencies result from poverty and the inability of people to have enough of the necessary foods to make up an adequate diet.
Nutritional deficiencies stem from not having enough to eat. Period.
The scary iron deficiency story from SE Asia alluded to by Zimmer in the Times — “researchers estimated that the rate of iron deficiency may rise from 21.8 percent to 27.9 percent by 2050” — is a Paris Agreement promoting piece of advocacy that assumes that the diets of the poor in these areas will remain unchanged, that there will be no advances in standards of living, food security or primary foods; no public health advances, no health education efforts; no vitamin supplementation programs where already desperately needed — in other words, the projections are based on a “the world stands still” scenario — and the only variable is the “projected” generalized decline in iron concentrations in “crops”, which is based on speculation — not on the foods actually in the diets of the affected peoples. Iron in human diets comes primarily from meats though there are good plant sources as well. Iron deficiencies arise where diets include little or no meat due to poverty and where lack of education deprives the people of the knowledge of plant-based alternatives. Paper @ “Anticipated burden and mitigation of carbon-dioxide-induced nutritional deficiencies and related diseases: A simulation modeling study”.
This small article in the New York Times on Vitamin A — which represents a much larger world-wide problem — exposes the simplicity of dealing with any such problem should it actually arise: “What a Little Vitamin A Could Do”. A single liquid Vitamin A capsule squeezed into the mouth of each newborn baby averts a very high percentage of Vitamin A Deficiency caused childhood blindness. Cost? 2 cents (less in bulk).
“Death by Diet” in today’s world is not caused by incremental differences in nutritional values of foods. That is a myth — the same myth that, on its flip-side, brings us “SuperFoods” and causes people to buy expensive amaranth, quinoa and other minor “ancient” grains in preference to inexpensive and abundant wheat, rice, rye and corn.
Of course, diet is important. But the basis of diet for a majority of the world’s people means “what we can grow or collect”; “what we can afford to buy” and “what we think we should eat”. Herein lies the entire problem of malnutrition in the world today. It can be reliably solved through the process of raising standards of living for the abjectly poor, education of children (especially women who will bear the burden of making diet choices for their families) and public health care that includes vitamin and mineral supplementation for the poor (particularly children) until their diets can be improved to meet their needs. Some of this education outreach must include agricultural methods to improve yields (which raises standard of living) and encourage the culture of a wider variety of garden items for the family diet (which eliminates vitamin and mineral deficiencies).
Senselessly worrying about small incremental changes in nutritional values of different crops under higher CO2 concentrations does not lead to any solution and does not solve the nutritional problems of the world’s poor. Just as the “soil depletion” scare passed away under the wheels of time, so will the “CO2-induced lack of nutrients” scare pass away — it is no more significant than its food fad flip-side, SuperFoods.*