In the 1960s, foods were prepared at home and had more fiber than ultra-processed foods produced nowadays. The average intake of starch was correlated (R=0.74) with the average consumption of bread, cereals, legumes and potatoes. The average intake of starch varied from 10 % of energy in the US to more than 50 % of energy in Japan. The average intake of starch was inversely related ecologically to 50-year CHD mortality rates among the 16 cohorts (R = -0.71).
Average starch intake and 50-year CHD death rates
US: US railroad; EF: East Finland; WF: West Finland, ZU: Zutphen, the Netherlands; CR: Crevalcore, Italy; MO: Montegiorgio, Italy; RR: Rome railroad, Italy; DA:Dalmatia, Croatia; SL: Slavonia, Croatia; VK: Velika Krsna, Serbia; ZR: Zrenjanin, Serbia; BE: Belgrade, Serbia; KT: Crete, Greece; CO: Corfu, Greece; TA: Tanushimaru, Japan; UB: Ushibuka, Japan
These results suggest that plant foods rich in starch and fiber, may protect against CHD mortality. Unprocessed plant foods contain the carbohydrate starches amylose and amylopectin and non-starch polysaccharides (total dietary fiber). In contrast, ultra-processed foods contain amylose and amylopectin but without fiber. Starch is inversely related to CHD mortality ecologically. Controlled dietary experiments support replacement of added sugars by starch to reduce LDL-cholesterol level, an established causal risk factor of CHD.