A research review published in Nutrition Reviews has found that while protein supplements effectively increase lean mass in all users, consuming them between meals promoted weight gain. Consuming them with meals, however, helped with the maintenance of body weight while decreasing fat mass.
“It may matter when you take your supplements in relation to when you eat meals, so people who consume protein supplements in between meals as snacks may be less likely to be successful in managing their body weight,” said Wayne Campbell, professor of nutrition science at Purdue University and senior author on the study.
The researchers suggest that timing of protein supplements might impact the amount of overall calories people consume, with those downing a shake with their lunch eating less than they usually would.
“Such dietary compensation is likely missing when protein supplements are consumed as snacks. Calories at meal times may not be adjusted to offset the supplement’s calories, thus leading to a higher calorie intake for that day,” said Campbell.
“If the goal is to manage weight, then snacking on protein supplements may be less effective. People who are trying to gain weight may consider consuming protein supplements between meals.”
Despite the growing popularity of supplements, this is the first time the issue has been investigated and Campbell says it will need to be followed up with further studies.