Are protein and fiber obtained from "shakes" used by the body as effectively as if they were obtained from unprocessed foods?

Question

Recently I've been frequently consuming protein/nutrition shakes. Sometimes I make them myself using whey protein powder or a mix. Sometimes I buy them from cafe's such as Starbucks' protein/fiber powder containing Vivanno, or one of Jamba Juice's offerings.

I've been wondering though - am I really getting the full benefit of these nutrients when they've just been added to a drink in powder form? Or do I have to actually eat more natural foods like beans, eggs, meat, vegetables, etc, to get the full benefits? Is there any strong evidence one way or the other?

Answer 1

The more processed and isolated the nutrient, the easier it is for your body to digest and make use of it. That's as true for protein as it is for carbs and fats.

That said, you will never have 100% absorption rate of any nutrient. Some of it will be lost in the digestion process, and the protein powders from GNC (much less Starbucks) are not as pure/isolated as you might find from a Lindora or Ideal Protein shop. I don't see that as a bad thing.

Keep in mind that over-consumption of protein (i.e. more than your body needs to repair muscles) will result in that protein being converted to blood glycogen in the kidneys. The release of energy is through a very slow and thermogenic process (i.e. it takes a lot of calories to do it). However, with enough of an increase it will elevate the blood sugar levels to generate an insulin response.

Part of the advantage of real food vs. processed food is that your body is inefficient at processing it. Because the body works harder, it consumes more Calories to digest the food.

Let's look at some references:

• Wikipedia: Protein (lots of studies linked to here)
• Livestrong Protein Powder Facts
• Supplements vs. Food, Which is Superior
• Protein Supplements vs. Protein Foods