One of the most popular and widely used nutritional supplements on the market is whey protein. But don’t let its popularity fool you. Whey protein has it’s limitations and drawbacks. Let me explain.
Whey protein, both as a standalone supplement and source of protein, has major shortcomings when it comes to protein absorption and insulin management.
The International Journal of Sport Nutrition and Exercise Metabolism published a report in 2006 that found whey protein isolate to absorb into the body at a rate of about 8g/hour. The problem is, the window of opportunity for whey protein to be absorbed during the digestive process is approximately 1.5 hours, so regardless of how much whey protein you consume in your post workout shake, your body will only be able to absorb approximately 12 – 20g of it.
In short, if you drink a whey protein shake with 40g of whey, more than half of that protein is never absorbed by your body (basically, it just gets excreted.) Whey protein simply passes through the system too rapidly to be adequately absorbed at high doses.
A 2012 study published in Nutrition & Metabolism found that the specific amino acids in whey protein stimulate beta cells to secrete high levels of insulin. How hight? More than a similar amount of carbohydrate from white bread. Whenever you find a story that is comparing part of your diet to white bread, you know it’s time to pay attention.
Too much insulin reduces your body’s ability to burn fat. so it’s important to choose foods that elicit a lower insulin response when on a weight loss plan. In other words: whey protein is not as good as other, lower insulin producing, forms of protein such as those found in real animals or slower digesting protein blends.
You might be left wondering if it’s possible to get the positive benefits of whey without the downsides of low absorption and high insulin response. The answer is, yes: if you combine whey with other medium-speed and slow-digesting proteins such as milk protein and micellar casein.
Combining you whey with other proteins will reduce the overall insulin response from the whey while ensuring optimal absorption due to their slower digestion rates.