I was telling a professional, when my wife was not eating much, that she tended to prefer sweet things. 'Ah yes, they develop a sweet tooth'. Me: 'No. She's always had a sweet tooth'. 'Ah yes, it's very common. They develop a sweet tooth.'!!!!!
However, some people with dementia do seem to develop a sweet tooth. But I have recently learnt that, as people get older, the taste buds begin to disappear (along with many other things!) and, with far fewer taste buds, people tend to favour foods that make the strongest impact, e.g. sweet things. People with dementia are predominantly elderly.......
So mostly it's not to do with having dementia, it's to do with ageing. I definitely know that my sense of taste has deteriorated, and I probably like sweet things more. I am quite old but I don't have dementia.
Another example. Plates of a certain colour are allegedly easier for people with dementia to see the food on. But, guess what? There's no agreement about which is the best colour - yellow, blue, red - because everybody's different. And the issue could be to do with deterioration in the eyesight (i.e. the actual eyes becoming less efficient) or with problems relating to the link between the eyes and the brain (which are a feature of some types of dementia). So when someone says 'Yellow plates are best for them', they might be right about some of them but, even for those some, the problem could be to do with ageing rather than with the dementia.
There are so many examples of this attempt to portray 'people with dementia' as almost a different species. They are, of course, just people.....who happen to have dementia.