I drank Carnation Instant Breakfast VHC which has now been replaced with Boost VHC (very high calories) which has over 500 calories in each 8 ozs with every meal. I mixed mine half n half with whole milk.

I would ask for a peg... And maybe try making your own formulas - much as Eric does - with fresh natural foods and a protein supplement - I have a power shake every morning - though I don't use whey - I use a combination of non whey- non soy - vegan protein powders with fresh fruits organic cottage cheese, unsweetened almond milk and flax. It gives me a boost for the day and energy to boot. I was in Italy for two weeks and bought a blender there and brought my own powders, and started most days off with a toned down version of my usual shake. I have to say I missed my usual stuff - Italy has no unsweetened almond milk - though I did find a place in Florence at made their own - fruits - like bananas and berries were somewhat hard to come by and flax and cottage cheese? Not so much. I did find bananas in two cities, so I would use a bit of soy or almond milk - a banana and the protein. NOTthe same - it was like a power trek all over Italy and my energy was good, but not near what I have at home since the diet there is limited to pasta - pizza, grilled veggies (the same damn ones) rice balls, potatoes, and tomatoes and bocconcini. At one point I told my husband I would kill for some corn, beats and any veggie other than eggplant and zucchini. My point is this diet is very important.... Even if you can't get the full amount of calories, the quality of the calories is important. Junk will not feed your body. Maybe if you have to do a combination of formula and your own blended stuff. Put the formula down your tube and then make a couple of shakes for yourself and take your time drinking them throughout the day. Hugs and good luck,