There's nothing wrong with wanting and trying to be healthy. As a matter of fact, more people should strive for it. But it's important to remember "everything in moderation," the old saying that implies that a good thing, taken to an extreme, can be bad for you.

Such is the case with orthorexia, a term used for people who are preoccupied with avoiding foods they believe to be "bad" or unhealthy, without the primary focus being about weight.

A person with this type of food obsession thinks the foods he or she is avoiding are unhealthy, but that may not be the reality. For example, one orthorexic person may avoid all carbohydrates when, in many cases, carbs have important nutrients and are healthy for us. Another may refuse to eat any kind of bread, even though it can be a nutritious food for a healthful lifestyle. Bread has been around for centuries and is a part of almost every culture.

The belief system of the person with orthorexia is not a rational one. It is a rigid and often quirky to downright abnormal way to approach eating.

Oftentimes, this obsessive-compulsive thinking gets out of control, resulting in ill health and an unbalanced life. Take Patty. She wasn't anorexic or bulimic, but her life had gradually become as unmanageable as that of people with those better-known eating disorders.

It started innocently enough.

She was concerned about eating more healthily so she went on a popular fad diet touted to be the latest in cleansing the system to help her body "get on the right track." As with many things Patty attempted, her perfectionism made her want to do a perfect job at being healthy and following the diet. With time, the number of foods she would allow herself to eat was reduced to four. It wasn't easy eating just four foods each day. That meant other things had to change also. So she stopped socializing for fear of confronting situations where "forbidden" foods were present. Before long, her life was limited and she was socially isolated. Patty started all this to improve her health but instead compromised her health physically and psychologically.

Unfortunately, cases like Patty's can be difficult to treat because such people often don't think there is a problem. On the contrary, they feel virtuous in what they're doing. Denial can keep them from seeking help.

In addition, we now live in a society that often reinforces many eating behaviors that aren't normal or adaptive. Some popular fad diets encourage behaviors that are extreme and even unbalanced nutritionally. Many people don't think twice about someone on a diet that discourages all starchy foods or particular fruits that are considered to have too high a glycemic or sugar value. It seems that the quirkier the diet sounds, the more people pay attention and think it's the right thing to follow. People have become accustomed to messages of this type and tend to view them as normal. As a result, we may view people who have extremely rigid control of foods as admirable, not unusual.

Orthorexia is an example of something that has gone awry despite good intentions. The irony is that in an attempt to be the healthiest people ever, those with orthorexia have made themselves sick — psychologically and frequently physically — and often are unaware of the downward spiral they've been on.

Balance, both physiologically and psychologically, is healthy. When we don't have it, we head toward ill health.

When it comes to eating, the healthiest people are those who practice flexibility and moderation. They strive for good nutrition but don't expect perfection. And they always allow space for the psychological pleasure that comes from eating.

Dr. Lavinia Rodriguez is a Tampa psychologist and expert in weight management. She is the author of "Mind Over Fat Matters: Conquering Psychological Barriers to Weight Management." Send questions to her at drrod@fatmatters.com.