Zuckers!! - Protein vs Atmosphere Co2

http://www.dailymail.co.uk/wires/reuters/article-4757332/Protein-risk-millions-rising-CO2-emissions--study.html

http://www.nature.com/nature/journal/v510/n7503/full/nature13179.html?foxtrotcallback=true

http://www.ndtv.com/food/rise-in-carbon-dioxide-may-trigger-protein-deficiency-in-18-countries-harvard-1732354

https://www.wionews.com/world/global-warming-reduces-protein-in-key-crops-study-18491

So the rising Co2 in the future will cause less protein in the food, but is this true in the past as well?

Is the rise of Co2 a root factor in the obesity epidemic? And then we can grow protein, but which protein?

Is this an answer, or just more noise?

In 1950 Co2 was at 280ppm, winters were cold here, snow was deep, and hogs could be raised on the local barley. By 1960, Co2 was at 315ppm, and hogs need concentrate, iron supplements, antibiotics, and other supplements to survive on barley. We blamed chemical fertilizer for the increase in carbohydrate and reduction of protein in the grain. But was it the Co2 effect? Now we are at 400+ ppm, and we have an obesity epidemic. Are these just Co2 rise effects?