Many dieters who fail to carefully research and plan complain that they lack energy - and often experience a significant loss in muscle mass. Others observe a number of other more peripheral problems that come with a poorly-planned vegetarian diet.

The first group--the group that most failed dieters fall into--is actually experiencing a form of protein-energy malnutrition (PEM). PEM emerges when a person fails to consume enough protein, leading to muscle loss - and subsequently feelings of weakness that are often accompanied by head and muscle aches.

This problem can be circumvented by dietary alterations. A vegetarian who is experiencing PEM should either a) find out what foods contain what amino chains, so they can combine them to form proteins; or b) start consuming larger amounts and more diversified sources of protein, such as nuts, soy milk, and yogurt.

The first group is often iron-deficient as well. Because vegetarians can only consume nonheme iron, which is more sensitive to iron inhibitors, they often do not consume enough to maintain healthy blood-iron levels. This can cause pervasive weakness and even anemia.

Most nutritionists suggest that vegetarian and vegan dieters consume roughly twice the recommended amount of iron while greatly reducing their consumption of iron inhibitors.

People in the second group--the smaller one--who suffer from a range of other peripheral, diet-related problems are often not consuming enough of the nutrients that they would normally take in unknowingly on a diet that includes meat and dairy products. These nutrients include, for example, zinc, calcium, vitamin b, and riboflavin.

Some recent studies have suggested that vegetarians also process certain types of foods with less efficiency because they consume different amounts and varieties of absorption inhibitors and enhancers.

Recent studies also suggest, however, that a vegetarian or vegan diet, when done right, is not only as healthful as a non-vegetarian diet, but it is also much more heart-healthy - and usually contains higher amounts of antioxidants.

What does this all mean for you as a prospective vegetarian? It means that eating a healthful vegetarian diet is not only a good alternative to your current diet, but it can also lower your chances of getting heart disease and cancer.

However, in order to eat a HEALTHFUL vegetarian diet, you must actually put in the time to research and plan; if you don't, you most certainly will end up in one of the two groups discussed above.