...cos I do! Mainly my mother. I see her 2 times a week, both for meals (one here, one there).
I have only been dieting for 17 days (post a holiday where the snaps revealed what I already knew to be true
), I have lost 10 lbs as of this morning but that's from a start of 13 stone so it's early days; however, experience has taught me not to mention it to my mother.
I have always been prone to being a bit overweight which has, over the decades, prompted her to make the odd 'aside' remark. She is now just nudging size 16 at 78 (but it's that 'older person thickening' rather than a big wobbly tummy and no bum you sometimes see!) so has never really struggled with her weight, but:
a) She has some funny ideas about dieting, like the 'eat three solid meals a day and never snack' which sounds good but doesn't specify WHAT those meals need to be and flies in the face of other, now-known research about hunger, GI, GL and insulin, for example, and
b) has smoked 40 a day since her 20s.... this is not to be seen in any way, shape or form to be contributing to her ability to not get fat, you understand, and you are dared to mention that the once she did stop smoking for 2 years in her 50s, she started again because of the weight gain..... 
I have also not advertised the fact at work. There are a few of us 'older ladies' who are over-weight so we have a group moan and I duly join in the talk about 'being good' even though I don't think any foods are good or bad or that people are being 'bad' if they choose to eat a slice of cake, of which there is usually plenty!
I think that making your weight loss plan public can work for some people but not necessarily for me. I want to lose weight for me, not for others. And I hate that 'oh, you don't need to lose weight' thing! (at 5'6", 13 stone and a BMI of 30, yes I did!). Sure, I will graciously accept any compliment about my weight loss but I'd also brush it off rather than launch into 'my diet plan'!
What about you?