I chose whey protein isolate in the end due to the lower carbs and fat being in it. Below is part of an article I read from a nutrisionist that offers advice bariatric patients.
Weight loss surgery makes protein shakes essential
Whether you're considering bariatric surgery or have already had it, getting your protein is going to be a very important part of your life. (Read more on the pre-weight loss surgery diet and post-weight loss surgery diet.)
However, it may be hard for you to get all the protein you need from "regular" foods for a variety of reasons.
That's where and why protein shakes/protein powders come in to the picture.
Which protein source is right for you?
I suggest trying whey first, then soy or egg, and then any of the other plant sources named above. You'll get the most protein for the least calories from whey, egg, and soy. I recommend your shakes fall in the 150-250 calorie range.
Protein Shake/Protein Powders: How much protein do they provide?
This varies depending on the brand. First of all, read the serving size! A serving is typically "one scoop" but occasionally it will be "two scoops."
Then read the label for the number of grams of protein per serving. Choose a product with at least 15 grams of protein.
How much daily protein you need varies but generally is in the 60-80g/day range. (Be sure to follow the recommendations of your physician.) If you have two shakes per day with 15 grams protein each, you'll get half your daily requirement by drinking 2 shakes.
If you mix protein powder that has 15 grams of protein with 1 cup skim milk/lactaid milk your resulting shake will be even higher in protein: 23 grams. Then 2 shakes provide 46 grams per day.
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Solid Food Contributes to Your Overall Protein Intake TOO
It's useful to know how many grams of protein you need to eat every day so you can understand how your bariatric shakes contribute.
For example, you don't need to drink two 40 gram bariatric shakes if you're eating solid food too. Keep in mind that every ounce of poultry, fish, meat, or cheese has 7 grams of protein:
Food Amount Grams Protein
chicken 1 ounce 7 grams
turkey 1 ounce 7 grams
fish 1 ounce 7 grams
canned tuna/salmon 1/4 cup 7 grams
beef, pork, lamb, veal 1 ounce 7 grams
cheese, nonfat/lowfat 1 ounce 7 grams
cottage cheese, nonfat/lowfat 1/4 cup 7 grams
milk, skim/nonfat, or 1% 1 cup 8 grams
yogurt, nonfat or lite 6-8 ounces 6-14 grams
Greek yogurt, nonfat 6-8 ounces 13-14 grams
egg 1 7 grams
egg whites 2 7 grams
egg substitute 1/4 cup 7 grams
beans 1/2 cup 7 grams
tofu 1 ounce 2-5 grams
peanut butter 2 Tablespoons 8 grams
nuts/seeds 1/4 cup 5-6 grams
protein powders/protein shakes 1-2 scoops/3-20oz varies