Answer: Sports Nutrition Editor
I usually tell people to either take a 1/2 serving of a meal replacement powder (MRP), or to take a whey protein. Here's why. The advantage to the MRP's is they usually contain milk proteins like casein or milk isolates. These proteins take longer to digest and you'll feel full for a longer period of time than a whey protein. MRP's contain about 40 grams of protein, 24 grams of carbs, and 2 grams of fat with 275 calories. It's the carb content that makes me hesitate slightly with an MRP and is why I recommend only a 1/2 serving.
My first choice is a whey protein. They are very low in carbohydrates and you can adjust the serving size to equal about 20 grams of protein, 3 grams of carbs, 1-2 grams of fat with 100 calories. If this is the core of your meal, you still have extra calories to use up on solid food you can chew like low glycemic fruit or vegetables. You should drink these shakes several times a day in addition to one or two other small feedings.
MRP's add vitamins and minerals whereas most whey powders don't. However, you shouldn't rely on a MRP solely for vitamins which is why I recommend a good multi vitamin during calorie restriction. Also, add a tablespoon of flax oil or other 'good-for-you' oils to your shake. You need it for hormone production, good skin, to stay healthy and it will help slow the digestion of your shake satisfying you for a longer period of time.
An interesting study at McGill University put two groups of people on a moderate exercise program similar to most of us 'weekend warrior' types. They were not dieting. One group got 10 grams of whey protein morning and afternoon. The other group got casein (a milk protein). After 3 months the whey group lost a small amount of bodyfat with little change in the casein group. Peak cycling power output increased about 13% in the whey group and was essentially unchanged in the casein group. Glutathione levels, which is a measure of good immunity, increased about 35% for the whey group and was unchanged for the casein group. It's the change in bodyfat levels that makes me give the edge to whey protein.
You might ask, "What is whey or casein?" Milk protein is about 20% whey and 80% casein. Casein is the protein found in cottage cheese and cheese. For me, I'm at the weight I want to be so I'll have a full MRP in the morning for breakfast and 2 whey shakes later in the day to add protein.
Answer: Lindberg Store Manager
Soy protein powder is really popular now due to its cardiovascular benefits. For dieting, it has a stronger effect than other proteins on several thyroid stimulating hormones. One of these hormones, thyroxin (T4), helps regulate your metabolism and how fast you burn calories. You might want to add a scoop a day into one of your shakes for this reason.