A constipated woman lost more than 10 years of memories after straining too hard on the toilet, it is claimed.
The anonymous woman had a 'mental blackout' because of constipation, according to reports from Hong Kong.
The China Post claims the woman forgot a decade of her life for an eight-hour period after struggling on the toilet.
Her memory returned after an overnight stay in hospital, although she still cannot remember the eight hours after her visit to the lavatory.
Neurologist Dr Peng Jiaxiong told reporters that the woman suffered from 'transient global amnesia', a mysterious condition resulting in sudden memory loss.
Dr Sarah Jarvis told The Sun : "In theory, it is possible to explain someone losing their memory as a result of excessive straining at the toilet.
"If you are physically pushing very hard, you could cut off blood supply to the brain.
"You might see the same thing if you were lifting a very heavy load.
"In extremely rare cases this might even lead to a bleed inside the brain, causing a form of stroke."
However, the doctor told the newspaper significant memory loss was rare and said she had not seen a similar case in her 30-year career.
Bodybuilders have been known to suffer blackouts during extremely intense workouts.
The problem, known as vasovagal syncope, can be brought on by lifting heavy weights.
The Lancet, a medical journal, found that bodybuilders passed out because of a lack of cardiovascular exercise and poor blood flow to the brain.