Welcome to Straight Talk on Health. I’m your host Dr. Chet Zelasko. Straight Talk on Health is a joint production with WGVU in Grand Rapids MI. I examine the practical application of health information. Nutrition. Exercise. Diet. Supplementation. I look at the science behind them, and let you know whether it’s something to consider or not. You can check out other things that I do on my website Drchet.com and sign up for my free emails.
I’m back from a weekend trip where I talked to many people about their nutrition questions. One of the great advantages of these trips is that I know what nutrition questions are most important to people right now. Combined with what I get asked via email, and those questions add up. So let’s talk about shakes and smoothies.
I prefer chewing my food. I’ve tried shakes and smoothies, and they just don’t do it for me, but it’s become a convenient and nutritious way of life for many. As I suggested, I’ve gotten a number of questions on what you should and maybe shouldn’t put into smoothies, so let’s cover several of them as well as other questions.
Let’s begin with digestive enzymes. The typical digestive enzyme supplement has several different enzymes to digest food. There are proteases to digest protein, lipases to digest fats, several enzymes that can break down different classes of carbohydrates, and many also have lactase to digest lactose, the milk sugar.
What would putting digestive enzymes in smoothies do? Some enzymes require stomach acids to activate. More than likely, other enzymes would start to breakdown the nutrients they’re designed to digest. Is that a bad thing? Not necessarily, unless you leave the smoothie to sit for hours—which is exactly what you want to avoid. It may change the flavor if it sits too long but otherwise, it should be fine.
What about probiotics, another popular ingredient most people want to add, either from yogurt or another complementary nutrient. Would there be any issue with adding probiotics to smoothies? No, as far as I could find. It’s the same idea as with the digestive enzymes: the probiotic will start to do its job, which is to ferment once it’s fed. Starches, prebiotics like inulin and dextrin, and fructooligosaccharides (FOS) are the preferential foods for the microbes.
Adding fruit or vegetables to the smoothie would be adding some FOS as well as some naturally occurring fibers. Again, just like the digestive enzymes, the shake would have to be left out a long time for any reasonable fermentation to occur. One more thing: while the probiotics would have fluids and food, the one thing they would not have in a smoothie is heat. Probiotics are not likely to start fermentation when they’re closer to refrigerator temperature than internal body temperature.
And one more thing. Would putting the probiotics in a blender at high speed damage the bacteria? The answer appears to be “no” based on comments from scientists who do research on bacteria of all types. Imagine trying to slice a mosquito with a chainsaw; the blender’s blades aren’t small enough to slice and dice the bacteria, and the heat the blades generate isn’t enough to damage a significant amount of probiotics. On top of that, there is the law of large numbers. The average probiotic has between .5 to 2.5 billion colonizing forming units in them. In a less than a gram. If they are that small even, if a few million are damaged, you still have potentially billions left. The one thing that will destroy probiotics is heat over 165 degrees, so don’t put them in soup or hot drinks.
How about one more thing you might want to add to your smoothie: fiber. In this case, it depends on the type of fiber more than anything else. Let me illustrate. My grandson Riley have something we call soup almost every night. It is two kinds of fiber—more in a moment—as well as probiotic mixed with water. Riley can be pokey when eats and sometimes, it carries over to when he drinks liquids. One evening, when I wasn’t paying attention, he didn’t drink his soup quickly enough. It turned into a jelly like consistency. The reason is that one of the fibers I put in the blend is ground psyllium husks. While it is great fiber, that’s one of its characteristics inside the gut—to turn into a gel. It will do the same thing if you take too long to drink your smoothie.
There are some fibers that don’t turn to gel quite as fast as psyllium husks such as inulin, pectin, guar gum and digestion resistant maltodextrin. These fibers function differently than psyllium fiber. I don’t know that I would prepare them the night before and let them sit in the fridge overnight. But hey, if you’re willing to give it a try, go for it. Just let me know how it goes.
Here's what I can’t help you with. There are many green powder products on the market. I’ve examined several labels and they seem to contain everything including the kitchen sink. I understand dehydrates from fruits and vegetables although it has to be done properly so as not to destroy the phytonutrients in the powders—the whole point of the powder to begin with. But there are exotic vegetables and fruits. With so many included, it’s tough to know whether first, there are enough of each to do any good. Second, whether they will interact with other nutrients. I know we eat different foods mixed up all the time. But while we think of the green powders as food, they don’t have the natural water and fiber found in foods. Whether that impacts efficacy or not is unknown.
Then, there are the herbs that are sometimes included. Herbs are not without medicinal value—even things like chamomile and ginger have been used to ameliorate symptoms. What might interfere with what? I just can’t begin to tell you.
One more thing, because I get this question that applies to protein shakes. If you take essential amino acids, don’t put them in with a protein smoothie. The objective of the EAAs are to stimulate muscle recovery, repair, and growth. Taking the EAAs with protein from any source may neutralize the benefits of the EAAs. They contain the top three AA for growth and repair - leucine, isoleucine, and valine. They need just a little time to get a head start to the muscle before protein interferes with absorption which may neutralize the effort of the EAAs. The research isn’t clear and maybe I’m overthinking it but if I’m going to try to stimulate muscle growth after hard workouts, I’ll take the time to do it in a way that may provide the best benefits.
Those are the questions related to smoothies and shakes and questions about what you can add to them. How about just one question about exercise? Should you eat before you work out or wait until after you work out? The answer is Yes! I think it’s a completely personal thing. My best buddy used to eat and then immediately go workout. For me, it depends on when how hard I’m working out. If it’s slow and easy, I may have something light a couple of hours before I work out. But if I’m going to hammer it, I want an empty stomach. That’s why I favor working out in the morning because I don’t eat during the night. But that’s me so find the right timing that works for you and stick with it. The important thing is that you do exercise. Speaking of time it’s time for me to go so this is Dr. Chet Zelasko saying health is a choice. Choose wisely today and every day.
