How does weight influence development in older adults?

Development of what?

I'm not clear on what you are asking exactly. It is important to monitor their weight for any sudden gains or losses that could indicate an underlying health issue.Also daily weighing can give you a baseline on their weight. There are charts on line on what is an appropriate weight for a person of a certain age and height. Obesity for an eldery person is a problem just from the aspect of having diabetes might be a complication of it not to mention it would complicate mobility and their ability to clean themselves.A person to thin for age and height could indicate especially for a female osteoporosis,or digestive issues., or some issue causing weak muscles all of which can set them up for a fall. Would be most concern about sudden gains or losses. I weigh my mother weekly so I have a baseline weight on her and by keeping an eye on what she eats,drinks and her physical activity it helps creat a BIG picture of her overall health and how she is responding to her meds and environment. I don't know if this helps as again I wasn't really sure what you were asking but this is my 2 cents worth.