Hi Kelly,
First of all .. you are still young so that's good news as far as the elasticity of your skin is concerned. Genetic influences have a lot to do with skin "rebounding" also. It generally takes a full year after you have reached goal for your skin to "shrink" back as much as it will. Right now I think the best thing for you to do .. is not to worry about it and just part with the pounds. You can deal with any skin issues after you reach goal. As of now we really don't know if you will have extra skin or not. And if you do .. we don't know how much if any.
As to Kosher food .. the following are Kosher Dairy
Medifast 55 .. and 70 .. all flavors, Diabetic Shakes-- all flavor
Bars, Hot Cocoa, Cream of Tomato Soup, Cappuccino, Chocolate Pudding.. this is an older list so there may be more... for instance the vanilla and banana puddings.
Kosher Parve = The hearty Oatmeal .. all flavors and Robust Tomato Fast Soup.
I know there is a Rabbi in the plant that blesses the food.
In order to do complete program 6 meal replacements and no lean and green .. we really like to have a Dr. monitor you. You will need routine blood work. I personally have seen no real difference in the amount of weight loss between people who use the 5/1 and those who do a 6/0.
The real difference I see is when they transition back to other food.
It's a bit harder to transition when you've been on the 6/0.
I really believe if you do the 5/1 and follow the program exactly .. you'll do great and be very happy with the results.
Keep posting and let us know how you're doing. You are beginning on a wonderful journey to "thindom"
jan