A high protein diet could lead to early death, claim researchers

(Thierry de Lestrade) Salvatore Caruso, 108 

Too much protein during mid-life - especially protein derived from animal sources - could lead to an early death, according to US and Italian researchers.  In a paper, co-authored by Dr Valter Longo, at the USC's Longevity Institute, it is argued that people who eat a diet high in animal proteins during middle age are four times more likely to die of cancer than those on low-protein diets.  Statistically - and if accurate - this can be compared with the death rate from smoking. The study also concludes that for people over 65, a diet higher in protein could be beneficial. 

This is a fascinating study based on a large sample of adults tracked during nearly two decades. The data is compelling but additional research is needed to further understand the biological mechanisms at work.  The researchers have been criticized for comparing smoking deaths with those (potentially) from eating high protein diets.

According to the Guardian newspaper:  "Gunter Kuhnle, a food nutrition scientist at Reading University, said it was wrong "and potentially even dangerous" to compare the effects of smoking with the effect of meat and cheese as the study does."

Further coverage: LA Times
High-protein diets: Bad for the middle-aged, good for the elderly

Photo: Like others in the small town of Molochio, with one of the highest prevalence of centenarians in the world, Salvatore maintained a low-protein, plant-based diet for the majority of his life, but switched to a higher-protein diet after moving in with his son's family once he became frail.

Original article in Cell Metabolism + discussion threat involving authors 

PDF: Low Protein Intake Is Associated with a Major Reduction in IGF-1, Cancer, and Overall Mortality in the 65 and Younger but Not Older Population

Note: Dr Longo (cited above) devised the periodic fasting program that I am experimenting with this year.  I am intrigued - but not necessarily convinced - by the low/zero animal protein argument.  But after two months on a Vegan diet, I feel good and my weight management issues have all but disappeared. I will be fasting again soon for five days.