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Study under review: Effects of Dietary Protein Quantity on Bone Quantity following Weight Loss: A Systematic Review and Meta-analysis.
Introduction
Weight loss diets are widely considered to be a healthy endeavor but can come at the cost of lean tissue loss. The most well-known source for loss of lean tissue is muscle mass, but dieting off those excess pounds can also cause a loss of bone mass[1][2]. One of the major reasons this occurs is through physics: increased mechanical loading of bone is a strong stimulus for bone formation[3]. By reducing body mass, weight loss reduces the amount of force on the skeleton, resulting in bone loss over time[4].
Since high protein diets have been shown to help preserve muscle mass[5] during calorie restriction, it is possible that they could also preserve bone, especially since a lot of protein, in the form of collagen, goes into making and maintaining bone. Studies on the effects of dietary protein intake on bone mass during weight loss diets report mixed results, however, with some studies showing attenuation[6] of bone loss while others have shown neutral effects[7][8] or even increased bone loss[9].
Can increased protein intake help to prevent bone loss during weight loss diets? The study under review aimed to answer this question through a systematic review and meta-analysis of randomized controlled trials to assess the effect of dietary protein intake on changes in bone mass during weight loss diets.
Although weight loss can be healthy for people with obesity, weight loss diets can also cause loss of bone mass. The study under review examined whether high protein diets can preserve bone mass during weight loss through a systematic review and meta-analysis.
Who and what was studied?
What were the findings?
What does this study really tell us?
The big picture
Frequently asked questions
What causes bone loss during weight loss?
What should I know?
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