The question: I have started working out and need to increase the amount of protein I’m consuming. I try to get as much as I can from food sources. However, when looking for a protein supplement I am wondering what the difference is between labels that say “whey protein” and “whey protein isolates”? Is one better than the other?
The answer: You’re right; depending on the processing method, there are two forms of whey protein. Whey protein is made by extracting the protein component from whey, which is the liquid material that’s left after producing cheese.
Whey protein isolate is the most concentrated form and contains 90 per cent or more protein and little, if any, fat and lactose (the natural sugar in milk). Whey protein concentrate is less refined. It has anywhere between 20 per cent and 89 per cent protein. As the protein content increases, the fat and lactose content decreases.
In general, whey protein contains a higher amount of essential amino acids – amino acids the body can’t make on its own – than other protein sources. It also contains proteins that may help maintain immune function during intense training periods.
One downside to watch out for: whey protein can cause bloating and stomach upset. I have had a number of clients complain about this side effect.
When choosing a whey protein isolate product, look for one that does not contain artificial flavours and sweeteners. And avoid brands that contain excess sugar in the form of fructose, dextrose and maltodextrin. Pure whey protein powder should have less than 2 grams of sugar per 30 grams of protein.
Before you buy a tub of protein powder, however, determine if you really need it. Studies show that most people – athletes included – can meet their daily protein requirements from diet alone.
That said, some people do need protein supplements to help them meet their daily requirements. People who follow low calorie diets, vegetarians and those who train very heavily may benefit from a protein powder.
Send dietitian Leslie Beck your questions at firstname.lastname@example.org. She will answer select questions, which could appear in The Globe and Mail and/or on The Globe and Mail website. Your name will not be published if your question is chosen.
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