Most women get enough protein without turning to supplements, but a credible body of scientific research does support benefits of supplementing with protein powder. Results are not the same for everyone, but in a significant number of women, protein powder has the potential to produce successful weight loss, better body composition and lower risk factors for disease.
In a study published in 2007 in the journal “Metabolism,” obese women who used protein shakes as meal replacements over a 16-week trial period lost more than 10 percent of their body weight and 20 percent of body fat. The women followed a calorie-restricted daily diet consisting of fruits, vegetables, one full prepackaged entree and three protein shakes. All of the shakes used either soy or casein as their primary protein source, with the type of protein powder apparently not affecting weight-loss results.
Strength and Mass
Muscle mass is a particular asset for women because it is lean, it burns calories more efficiently than body fat and it makes it easier to perform everyday physical tasks. According to research published in 2006 in the “British Journal of Sports Medicine,” women who regularly strength train may be able to benefit from supplements such as whey powder because they provide high quality and quickly digestible protein, which encourages consistent construction and reparation of lean muscle fibers.
As they age, women experience sarcopenia, a gradual and natural loss of muscle mass. Osteoporosis is also a risk for women that increases with aging. In research published in 2013 in the “Journal of Women and Aging,” however, post-menopausal women who supplemented with protein powder and performed occasional resistance training over a 12-week period experienced significantly greater muscle and bone strength gains than women who went without the supplement, reducing their risk factors for both sarcopenia and osteoporosis. Women who took a daily soy protein supplement without exercising also experienced gains in bone and muscle strength, although to a lesser degree than those who supplemented and exercised.
Protein powder contains many of the same nutrients that whole sources of protein do, and there’s nothing the supplement can provide that the whole foods can’t. In fact, whole foods contain some beneficial phytonutrients and antioxidants that can’t be replicated in supplements, so they are typically healthier choices. The International Society of Sports Nutrition recommends whole foods over protein supplements for both men and women.
- M.D. Anderson Cancer Center: Whole Foods or Supplements?
- Physicians Committee for Responsible Medicine: The Protein Myth
- Metabolism: Soy Compared to Casein Meal Replacement Shakes With Energy-Restricted Diets for Obese Women
- British Journal of Sports Medicine: Nutritional Aspects of Women Strength Athletes
- NIH Senior Health: Osteoporosis -- Risk Factors
- Journal of Women and Aging: Effect of Soy Isolate Protein and Resistance Exercises on Muscle Performance and Bone Health of Osteopenic/Osteoporotic Post-Menopausal Women
- Journal of the International Society of Sports Nutrition: International Society of Sports Nutrition Position Stand -- Protein and Exercise