Though most people would agree that getting the nutrients our bodies need is best done by eating healthful meals and taking those vitamin, mineral, and other nutritional supplements appropriate for our particular needs, sometimes eating a meal just isn’t feasible. Maybe your schedule is so packed that you don’t have time to prepare food. Perhaps you’re traveling someplace during mealtime and can’t stop, or you need additional nutrition to get you through the day. Meal replacement shakes and bars offer an ideal solution for these problems, and they can help satisfy the additional nutritional needs of active bodybuilders. Meal replacement shakes provide high protein, moderate carbohydrates, essential fatty acids (EFAs), and all essential vitamins and minerals. Bodybuilders can drink a shake,  such as Nature’s Best Isopure and CytoSport Muscle Milk, to replace one of the numerous meals they must consume every day, or as an adjunct to a meal. Because of the many meal replacement shakes available, choosing the best one can seem daunting.

Soy or Whey?

Which is better, meal replacement products (MRPs) that use whey as the main protein source, or those based mainly on soy protein? The California Dairy Research Foundation reports that while different flavors are associated with whey than with soy, consumers perceive both proteins to be heart-healthy and useful for improving muscle and lean body mass. However, the CDR study also found that taste differences between soy- and whey-based MRPs were less noticeable in bars than in shakes.

Soy for Boys?

The soy vs. whey question is an important one for male bodybuilders, who tend to avoid soy protein in the untested belief that whey is superior to soy in supporting muscle weight gain. A study conducted in 2004 and reported in the Nutrition Journal directly compared a soy-based MRP with a whey-based one.

Research subjects were a group of men enrolled in a university weight training class who, for nine weeks, received micronutrient-fortified protein bars that contained 33 grams of protein from either soy or whey. A control group from the same class participated equally in the weight training but did not receive either type of bar.

Study results showed that both the soy and whey treatment groups experienced gains in lean body mass, but the control group did not. Interestingly, members of both the group that received a whey product and the control group that received no product showed a potentially harmful post-training effect on two antioxidant-related measurements. The group that received the soy product demonstrated no such effect.

Soy’s Slight Edge

Several research studies on using meal replacement shakes for weight loss indicate that people using soy-based shakes tend to lose slightly more weight that those who use meal replacements with milk products.

Regardless of your reason for choosing a meal replacement product and of protein base you choose, meal replacement bars and shakes offer a quick and convenient source of energy and sound nutritional benefit. And certainly, if the choice is between eating a typical fast food meal or a meal replacement bar or shake, everyone should choose the latter!

—Julie Crawshaw