The concept of meal replacement began as a weight loss technique.  Slim-Fast pioneered the idea that a shake or bar can replace a meal and help you lose weight.  Replacing a meal with a high-protein supplement is also used in bodybuilding. 

Protein is used for the production of skin, hair, bones, and muscles. Proteins and amino acids are used to manufacture hormones, enzymes, cellular messengers, nucleic acids, and immune-system components. Without adequate protein and the right balance of amino acids, our bodies can't create the structures that make up the cells, tissues, and organs.  Pritein is also needed for cardiovascular function, muscle contraction, growth, and healing. 

Protein in powder form or in bar form can assist in the building of muscle mass.  Protein intake is essential to anyone interested in being in good health, especially those who are active. Protein should be a core nutrient, especially when we're trying to maximize muscle and strength gains. The benefits of protein (especially whey protein) are clear, and increased protein intake may help us build a stronger, healthier body.

Good health includes the right balance of nutrition and exercise.  Too much of anything (including exercise and dietary supplements) can cause problems.  Always be sure to keep things balanced.