Here it goes, a lot of people don't agree, but I believe that my husband's results speak for themselves because he hasn't always been "heavy". In his JR and SR year of HS he was 6 foot and about 130-140 give or take some pounds.
Here's how he does his day. He eats every 2-3 hours. His daily goal is about 4000 calories, and 1.5 grams of protein per LEAN BODY MASS on days he lifts weights at the gym, .75-1.0 grams per LEAN BODY MASS. You figure lean body mass by taking a person's body fat percentage and multiplying it by their weight in pounds. For example, Mark is 12% body fat and weighs 195 right now, so I multiply .12 by 195 and get 23.4 Then I take that # (23.4) and subtract it from his weight in LBS. 195-23.4=171.6. So for mim 171.6 is his LEAN BODY MASS. On days he works out he sets his goal in the morning: 171.6x1.5=257.4 grams of protein. Now all that info I just gave you, put it in the back of your head, print it and put it somehwere for later.... once you son gets a little more weight/muscle.
To start out he should be eating about 115grams of protein daily, no more than he weighs right now because if he isn't eating that much currently, eating a signifigant amount more than usual can shock the kidneys and cause problems. So he may even want to do it gradually. Have him track what protein he is eating now and increas it by 10-20 grams a week. The same goes for calories, he shoud keep track of the calories he is eating now and increase gradually, at a rate of about 200 calories a week-a bit more if his body can handle it.
My husband pays ABSOLUTELY NO attention to his fat (or sodium) intake. So many CF clinics push fat, fat, fat intake, becuase CFers don't digest it well. That is true in-part, but CFers don't digest anything well, and protein and calories are more important to weight gain and muscle mass (which is muscle is clearly healthier than fat) than is fat. His CF dieticians caution him on not intaking a lot of fat, but he hasn't had a problem since he started doing it his own way.
He recently created an excel spreadsheet to log what he eats, and how many Protein Carbs and Fat the food item has. For example he will eat a chicken breast, so he will input 32, 0, 1.5 respectively. then the spreadsheet calculates the Calories. FYI- 1g protein=4 caloires; 1g carb=4 calories; 1g fat=10 calories. Then if he has rice with the meal, he will list that separately, then if he has an avacado (great source of fat, which equals calories too) so he can see where his protein fat calories and cars are coming from. I can email it to you if you like: division902@hotmail.com
He also drinks about 4-6 Boost plus shakes a day. He hates scandi shakes for two reasons: he says they taste pretty bad-and he's not really that picky, and they have MUCH less protein -I'll just get a can and a leaflte and give you the breakdown: Boost (same as ensure, jsut not name brand and a little bit cheaper) 360 calories, 130 calories from fat, 14g fat, total carbs 45g, protein 14g. Scandishake: 440 calories, 190 calories from fat, 57g of carbohydrates (more sugar than boost) and only 5 grams of protein. The scandishake does have more calories, but he finds he can make up those 100 calories elsewhere. The taste is just too bad for him, and he finds its easier to have a can he can take with him. He use to have 2-3 in his college bag, just in case he got hungry. We have a mini-cooler in the car that has about 6-7 of them so if he is hungry he just opens a can (or two). Quite frequently, insurance companies will cover these boost (or ensure, some like ensure better for flavor) shakes so if your son can stand them, it might be beneficial to look into. WE get an Rx of about 150-175 a month. If insurance doesn't cover them, maybe give it a month trial? It is 100% deductible for MEDICAL on your taxes (I can explain that too if you aren't aware of the CF food expenses being tax deductible).
He also does have his traditional shakes that he mixes up in the blender as well. There has been some controversy about this product because it has a diabetic warning on the side of it so if your son has sugar problems, I wouldn't recommend it because it has a LOT of carbs. But my husband gets 1/2 of his daily calorie intake from 2 BIG scoops of this stuff. It is called Serious Mass by optimum nutrition (you can google it, or MSN it and see a package and even review the protein/calorie intake per scoop). But that one is somewhat expensive (but I say, if it works and he uses it, it's worth it) and not all people like it, and some people have some sugar problems with it.
If you are interested in that excel spreadsheet, please email me. It will help your son see what he is taking in everyday and can help identify areas where he is lacking in his intake. Mark also lifts weights about 3 times a week (more during the summer). It can be very discouraging at first, especially if you are a smaller person who can't lift a lot, but you have to start somehwere. Now that Mark has signifigant and noticable muscle mass, he gets really pumped about working out. But the first year he was working out with weights, he was really frustrated. Luckly he foudn a really good, motivating workout partner who pushed him until he coulnd't go anymore.
Hope this helps a bit and email me if you want that spreadsheet.
Julie