Part 1 in this series reviewed some of the reasons why shakes and smoothies are so popular in modern society, and shared concerning findings regarding some protein powders. Let’s continue the discussion on shakes and smoothies!
Many people drink shakes or smoothies because they believe for one reason or another that they need to include more protein in their diet. In industrialized countries, protein deficiency is exceedingly rare. The evidencesuggests that protein intake is homeostatically regulated by the body. In other words, if your body requires more protein, there are complex processes that occur that will lead you to crave and eat more protein. If your body needs less protein, you will be averse to it and you will naturally eat less protein. A good example of this is during pregnancy in which many women become noticeably averse to various types of proteins. There is some thought that protein aversions during pregnancy may be an attempt by the body to limit protein intake as too much protein could be harmful to the fetus. Because of the tightly controlled regulation of protein intake by the body, the vast majority of people do not need to supplement with protein in order to meet their daily requirements and achieve their health goals.
For those that are participating in high intensity workouts, endurance sports, and other strenuous activities, post-workout nutrition certainly is important. However, there is absolutely nothing present in protein powder that cannot be obtained from real food. The goal of post-workout nutrition is to replenish glycogen stores and increase protein synthesis. Many athletes want to reduce recovery time, meet their muscle gain and/or weight loss goals, and enhance overall health. The healthiest way to do this is by eating real food! The composition of a post-workout meal may vary depending on your activity level and specific goals, but drinking your post-workout nutrition in the form of shakes and smoothies is not the best choice. Liquids require less digestion which leads to a rapid surge in blood sugar levels, instead of a slower and steadier blood sugar rise that occurs after eating a meal with protein, carbohydrates, and fat. This studyfound that whey protein has an insulin response that is 90% higher than the insulin response to white bread. Even though exercise increases insulin sensitivity, this type of drastic insulin response is not ideal.
Many people in the real food community drink smoothies without any protein powder added. Typically, these smoothies consist of green, leafy vegetables, fruit, and coconut or nut milk. Smoothies are often viewed as a healthy treat and an easy way to introduce more greens, such as spinach or kale, into the diet. However, the main problem with smoothies lies in their impact on blood sugar levels. In order to make these green smoothies taste palatable, most people add a hearty dose of fruit. Fruit does play a role as part of a nutrient-dense, real food template, but too many natural fruit sugars is not necessarily a good thing. Just as with the liquid protein shakes, smoothies hit the blood circulation quickly and require a faster and more marked insulin response. Smoothies are also not as satiating as a balanced meal. Drinking a smoothie as a meal replacement can lead you to become hungry more quickly and cause you to over-consume. Also, when you choose to drink a smoothie in place of a meal, you are missing out on a variety of other nutrients that you could be including in your diet.
In general, it is never ideal to drink your calories! Protein powders are highly processed and they cannot provide any nutrition that you cannot obtain through real food. Despite the common misconception, most people do not need to consume more protein. Both protein shakes and smoothies do have a convenience factor, but it may come at a steep cost of drastic blood sugar swings. When in doubt, it is always best to rely on eating real food to meet your needs.
What are your thoughts on shakes and smoothies? Do you think they belong in a nutrient-dense, real food template?