84 year old dad not eating much.

[Flyhigher]

He lives alone. Going to get a carer. And maybe a day centre.
What did people do to encourage DF to eat? And what foods?

Is it because he doesn’t want to prepare meals or due to a low appetite?
If he doesn’t have much appetite would he drink a nutritional shake such as build -up, ensure or fortisip? Some have 4-500 calories in and vitamins & minerals.
https://www.nutridrinks.co.uk/shop-by-category/elderly-nutrition
Would getting him a couple of small ready meals tempt him?

If you can narrow down the reason, that will help with possible solutions. Low appetite, trouble with food prep, not remembering, dental problems? But as a starting point I agree that easy ready meals and ready-to-eat snacks are often useful.

With my mum it was because she was becoming so forgetful she didn’t remember if she had eaten or not/wasn’t aware it was time to eat as she lost her sense of time. The start of dementia. I guess that must have been coupled with a loss of awareness of appetite. When you put a plate of food before her she wouldn’t be sure if she wanted it, but when she was encouraged to have a bit, she would wolf the lot. So for her it required someone setting a table or tray, putting the food on it, and saying “well try a bit now that I’ve made it, shame for it to go to waste” chirpily.

also making mealtimes v regular helps I think. Trains the stomach to expect it.

Finally my mum can’t resist fruit fools, yoghurts, that sort of thing so we had loads of those in, all high fat versions, to get some extra calories in her and put some weight on.

Cake. Rice pudding. Biscuits. Sugary tea. My DF pretty much subsisted on these.

FIL was like this at the start of Alzheimer's. He could pack away sweet stuff like pots of custard or trifles but put a dinner in front of him eg cottage pie or roast dinner - no!
Just try and get calories and vitamins in and the nutritional shakes. It's really hard I get it- my own mum (last one standing from MIL & FIL and my own Dear dad) is very ill - nearly 80 but still cooks for herself and eats a really hearty and balanced diet. I dread the day she stops it.
Get stuff in that is really easy to assemble- I'm taking mum to an appointment at hospital tomorrow and have a tub of Bolognese sauce I made yesterday to take round (was just our leftovers) but all she needs to do is boil up some pasta. I often make a casserole/ cottage pie so box up leftovers for her freezer so even if she feels rubbish there is an easy meal there. Much sympathy it's very hard seeing someone previously very capable not managing.

DH has been given a diet sheet for loss of appetite. It comes down to add butter and cream to everything In other words, if not much food is being taken, make sure it has a lot of calories.

Again if it’s loss of appetite, try and make sure everything he eats is one of his favourites. Don’t worry about nutrition rules we all live by.

If it’s lack of capability or forgetfulness, then he’s going to need help, social care, or meals on wheels if he’s lucky enough to be in an area that does it