I love this statement from the entry entitled “Sugar” in Wikipedia:
In modern times it has been questioned whether a diet high in sugars, especially refined sugars, is bad for health. Sugar has been linked to obesity and suspected of being implicated in diabetes, cardiovascular disease, dementia, macular degeneration and tooth decay. Numerous studies have been undertaken to try to clarify the position but the results remain largely unclear, mainly because of the difficulty of finding populations for use as controls that do not consume sugars.
Can we not find a control group anywhere?