My mother-in-law is 75 years old and will only drink Diet Coke. No water, no tea, no juice, no milk. She will tell you, almost bragging, that she hasn't had milk in 50 years. She suffers from stenosis of the spine, has weak pelvic/hip muscles and can't stand upright. She is also incontenent. The medication she takes requires she drink plenty of water when she takes them, and throughout the day. Her urine is so concentrated, the smell is overwhelming. I have offered to make her hot tea, bring her glass of sweet tea, orange or apple juice, etc. She ONLY wants Diet Coke. Would it be terrible of me to just quit buying it? She refuses to discuss it!
There are different flavors within the non-diet Coke and Pepsi family, such as Cherry Coke and Cherry Pepsi. Maybe give those flavors a try.
The carbonation that you can get with a Soda Stream isn't anywhere near that of canned carbonated beverages. I'm donating mine to my local charity resale shop. The quest continues.
Get a SodaStream (or similar) carbonation machine and carbonate your own water at home. These modern carbonation systems are lightweight, simple to operate, and take up very little counter space. You don't need to buy the expensive "soda flavors" that the carbonation machine companies sell (though you can try them if you like; maybe your MIL will find she likes the diet cola version).
Then just keep a bottle of carbonated water in the fridge at all times. When you serve a glass to MIL (over ice, if that's the way she likes soda), add a sweetener/flavorer of some kind to the glass of home-made "soda water." (You can find these liquid "water flavorers" in the aisle of the grocery store where they sell Kool-aid and powdered lemonade and such. They're meant to be added to bottled water. It takes just a few squirts to turn plain carbonated water into, for example, a diet orange soda.) I was a Diet Coke/Diet Dr. Pepper addict for many years, but converted myself years ago now to a carbonated water + either a low-cal liquid flavor (usually pomegranate or orange) or a jalapeno/vinegar mixture I devised for when I'm in the mood for something more tart.
When you're out and about, just carry one of the small "flavorer" containers with you (they're designed to be slipped into a bag or purse) ... you can order plain "soda water from the bar" of most any restaurant, or bottled sparkling water in a pinch, and add your flavoring on the go.
Anyway, I was thinking that if MIL really dislikes plain water (I can SO relate, if she does), and you'd like her to at least try taking her pills with something more likely to provide actual hydration, this might be a great alternative to plain water or Diet Coke to suggest to her for pill taking, WITHOUT pushing to take away her DC altogether ... she may discover she likes this alternative "soda," and if so, you may find you're able to offer it successfully during other times of day too.
(Personally, I'd be very leery of diluting Diet Coke with plain water. Any dedicated soda drinker is unlikely not to notice or object to a "flat" soda, which is what you get when you water down the fizzy stuff with the flat stuff.)
Something I do with my mother, who only wanted tea, was to start buying bottled water. Tea and coffee are diuretics, so I didn't want her to drink tea in place of water. She likes the bottled water. Sometimes if we run out I just fill the bottles with tap water. She doesn't know the difference. It's bottled, so it's special.
Bobbi here (one of the headlines on the home page and on the email I got) says her father was rushed to hospital in FL (she was in NJ) and it seemed a collapsed lung, pneumonia.... Then pulmonologist looked at Xrays and canceled emergency surgery, put him on IV fluids... Take hydration very seriously, folks. It takes effort but every hour and a half be sure they drink even a Half a Glass of water. I tried Coconut Water, and that's what I'd say you should mix some of into the diet coke... It's naturally got electrolytes, and you need to be consistent, but also they will be more Regular if there's enough Moisture in them to be able to Move the waste through their system. Fiber helps too, but water expands that fiber and makes it move through, ridding the body of toxins in the process...
Also I find articles that point to the dangers of soda via osteoporosis and what dehydration does... I found some things and I post some of these in my small ALF home in FL, Angel House....
Look up confessionsofafatwoman
I had them do an activity one day, finding pictures of water in magazines and cut them out to make posters. Sounds silly but try looking at pictures of waterfalls, beautiful clear, cool water, and not being thirsty for some! Even if it's a lake or river, maybe a glass of lemonade or water, people drinking water... looking all refreshed by it. There is power in these images. I hope this helps.
If the artificial sweetener is the problem, I'd surmise that at this point it's not going to cause much difference in her life span. Some people just dislike milk. I don't think I've had a glassful since I was about ten, which would make it 53 years without for me. You might encourage cheese, or even ice cream if you're worried about calcium.
My 87 year-old mother likes Strawberry Crush and the nurses always advise her to give it up and drink water instead. She really only drinks about half a glass of Crush a day, so we both politely ignore them. :)
Let's say you could get her to drink some milk. What would change? Would that cure her stenosis of the spine? Would she no longer be incontinent? How about if she had hot tea for breakfast each day? She'd probably pee a little more often in the morning. What else would change? If she had apple juice in the afternoon, would her hip muscles be stronger?
I agree that what you are suggesting -- more nutritous ways of increasing her fluid intake -- would be an improvement. But is the degree of improvement worth the cost of resistence and animosity it would engender?
If you stopped buying the Coke, what would that do to your relationship? What measurable improvements could you expect in her health?
Poor MIL has enough things she cannot control in her life. She can't stand up straight. She can't control her bowels and bladder. She can't get to the store and buy the products she prefers. I'd go very gently and cautiously on the you-can't-have-what-you-want-to-drink campaign. If you feel it is worth the effort, perhaps you could focus on one small change, such as taking her pills with a large glass of water instead of with Coke.
We caregivers have to pick our battles. I don't think Diet Coke is something I'd gird up my loins for, but you need to decide what makes sense in your situation.
Good luck!