Key points from article :
Michael Greger exams evidence that alternate day fasting prolongs life.
Anecdotal evidence has suggested a very wide range of benefits.
But actual affect on chronic disease remains unclear.
2007 study with overweight asthma patients suggests improvements - both physical and mental.
Could be attributed to weight loss over same period, rather than fasting itself.
Most comprehensive study carried out in Spain in 1956.
120 residents in an old age home split into 2 groups for 3 years.
Alternate days only ate fruit and milk (approx 900 calories).
Both mortality rate and days hospitalized higher in control group.
Group allocation may not have been randomised.
And not blinded - author controlled who went to hospital.
