On the other hand, dietitians have at least rudimentary knowledge about nutrition science. Dietitians need to take a variety of physiology, chemistry, and biochemistry courses, all of which are necessary to fully understand the science of nutrition and to separate erroneous nutrition information from facts. Registered dietitians need to take a national exam to make sure they are well versed in at least the basics. In many states, anyone can call him or herself a nutritionist and can set up a dietary counseling practice. There is a variety of certification programs that allow people to earn nutrition "degrees" with minimal training. So if you choose a nutrition counselor who is not a registered dietitian, you may not have any way of evaluating that person's nutrition knowledge.

Another thing that sets dietitians apart is that they know both nutrition and food. In addition to science courses, a dietitian's training includes coursework in food science and food preparation. While every dietitian isn't necessarily a gourmet chef, it is important to know your way around a kitchen and a grocery store when giving clients practical information about how to change their diet. Other health care professionals who have an extensive science background and who have read up on nutrition may not have much knowledge about food products and preparation. In one clinic where I worked, I remember a physician who kept telling all his patients to stop using salad dressing on their salads and to just sprinkle vinegar on top instead, ignoring the fact that there are plenty of non-fat alternatives that you can whip up in your kitchen or buy in the grocery store. Another health care practitioner once told all his patients to replace all the margarine in their diet with olive oil. I had visions of my clients pouring olive oil over their toast in the morning, instead of reducing the margarine!

I'm not saying only registered dietitians are knowledgeable about nutrition and food. There are plenty of people with hard-earned degrees in nutrition who have chosen not to go the registered dietitian route. And there are well-trained people in other fields who are extremely knowledgeable about diets.

The first step is to generate a list of registered dietitians in your area. There are a number of ways to locate a dietitian. You can check the Yellow Pages under nutrition, dietitian, or weight loss. (Even if you don't want to lose weight, this is a good place to look for a nutrition counselor.) Depending on where you live, there may be a lengthy list or no one listed at all. Another good resource is the American Dietetic Association's (ADA) referral service (1-800-877-2011). Tell them that you want a dietitian who specializes in vegetarian nutrition. The ADA has a specialty group of dietitians with an interest in vegetarianism. This Vegetarian Nutrition Dietetic Practice Group has 1,500 members. While that sounds like a lot of dietitians, bear in mind that all of them don't offer nutrition counseling and members have different reasons for joining the group. You can also contact The Vegetarian Resource Group (410- 366-VEGE) to see if one of our dietitian members lives in your area. Once you have a list of prospective counselors, you will want to call and interview them. Nutrition counseling can be expensive, and it pays to know ahead of time that this is a person who can help you and with whom you will feel comfortable. A 10-minute phone interview should be enough to help you determine whether this is the counselor for you.

Do be up front about your needs. You can quiz your prospective counselor endlessly and still not find what you need to know. But if you say, "I eat a strictly vegan diet and need to know that you are knowledgeable about that type of diet and that you are comfortable with this dietary choice," you should get the answer you need.

You might want to quiz your prospective counselor a bit regarding her knowledge about particular foods. If you use a lot of Asian vegetables, or build every meal around whole grains like quinoa and kamut, it helps if your nutrition counselor has at least heard of these foods and knows something about their preparation and nutrient content.

You will also want to know how the dietitian works. Does she take a personal approach? Look for someone who will work with your food likes and dislikes and your lifestyle to work out a menu pattern that is appropriate for you; you don't want to pay someone who is just going to hand you a standard vegetarian diet.

Finally, what is your gut feeling? When all is said and done, you have to like this person and feel comfortable with her. After all, this is the person to whom you're going to confess your deepest, darkest dietary secrets.

Most people go to dietitians because they feel that their diet is bad--and they often feel embarrassed about it. It can make it hard for them to be completely honest about those habits sometimes. Your dietitian needs to be shock-proof and completely non-judgmental, but at the same time she needs to help you identify problem areas in your diet. It's a hard act to balance, and it might be hard for you to judge, over the phone, the dietitian's ability to do this--but you may be able to get a feeling for how comfortable you are talking to this person.

In behavior modification programs, you would also be expected to note the time that you ate, the activity you were engaged in, whom you were with, and how you were feeling. Though most dietitians don't insist on that, there is some real benefit in logging this information. Many people who see dietitians need more than information about what is wrong with their diet. They often need to solve problems in eating behavior. Getting all the facts down about that behavior can really help to identify problems. Regardless of how much information you choose to log, chances are good that you'll learn something from your food diary. Some of the surprises might be pleasant ones--like you eat much more fiber than you realized. But you also might find that some of the vegetarian convenience items you are eating are pushing your fat intake sky high, that you eat fewer vegetables than you thought, or that you snack out of boredom.

Some people find that keeping a food diary is more than a fact-finding mission. It can actually help you to change your diet. Writing foods down forces you to think about what you are eating. You might find that this alone causes you to make better food choices.

The goals of a first 1 to 1-1/2 hour counseling session should be for the dietitian to have a clear understanding of why you are there and to get a good picture of your eating habits, to help you to identify areas of strength in your current eating pattern and areas for improvement, and to set up a specific plan for making necessary changes.

Your dietitian will most likely start by taking a brief medical history and will ask you to articulate the dietary problem. She may or may not weigh you and/or take your measurements so that you can measure your progress if weight loss is a goal. Personally, I'm categorically opposed to weighing and measuring but would rather measure success in terms of diet and exercise behavior changes.

Next, the dietitian will review your log, asking you to clarify some of the details. Then she will draw up a list of dietary strengths -- this is partly for some positive reinforcement, but also is part of your diet education. After all, if you are doing some good things, you want to know what they are so that you can keep doing them.

She also will identify the areas for improvement. Then it is time to brainstorm. Your dietitian can provide the basic information you need to know to correct the situation, but she will need your input to develop a strategy. For example, one problem might be that the only quick, easy lunch you can come up with every day is a fatty grilled cheese sandwich from the cafeteria at work. Your dietitian will be able to come up with a number of potential solutions to that problem -- but obviously you are the only person who can decide which of those solutions will work for you. If your vegan diet looks a little short on vitamin B12, your dietitian can come up with a list of vegan alternatives, including fortified foods and supplements -- but you need to decide which of those ideas you like and then work with the dietitian to develop strategies for getting those foods into your diet.

Once you've identified problems and solutions, your dietitian can help you to put the information together in a couple of different ways. She might work with you to put it all together in a menu plan; and indeed, many clients prefer to go home with something very structured and reassuring like that. Others are overwhelmed by the enormous difference between how they have been eating and how they are expected to eat. For people who have lots of changes to make and who are not in immediate danger, I prefer to prioritize changes, beginning with the easiest one. I suggest making one or two changes at a time. I also encourage clients to concentrate first on what is missing from their diet, rather than what needs to be deleted. That is, focus on getting 8 or 9 servings of whole grains, 5 or 6 servings of fruits and vegetables, and 2 or 3 servings of legumes in their diet every day. Once people learn to enjoy great-tasting, healthy foods, it becomes easier to work on reducing the fatty stuff.

For some, nutrition counseling can be a one-time experience. You may just need some basic pointers about your diet. Once in the right direction, you're you may be ready to take off on your own.

[Virginia Messina is a Registered Dietitian in Maryland.]