The ten most common myths about vegetarian diets

People have plenty of misconceptions about vegetarian diets, but a few particular myths about this style of eating have an especially strong hold. Some myths cause people to simply avoid vegetarian diets altogether because of fears that vegetarianism is difficult or dangerous. Sometimes people have such high expectations for a vegetarian diet that they lose interest when they don't immediately lose twenty pounds or feel healthier with a new vegetarian eating plan. Other myths can cause people to consume vegetarian diets that are unbalanced.

Clearing up some of these misconceptions provides a good practical start to eating more healthfully and happily. Here are ten of the "vegetarian myths" that we hear most often.

1. Vegetables grown in B12-rich soil can meet vitamin B12 needs.

A small amount of research shows that certain vegetables take up vitamin B12 from a growing medium that is rich in this nutrient. When the vegetables are dried to a powder (for the purpose of measuring vitamin content) the amount of vitamin B12 is fairly significant. But in the undried edible vegetable, B12 levels are modest--not nearly enough to make a significant contribution to needs. Right now, no commonly available vegetables are reliable sources of vitamin B12. Vegans need to use B12 supplements or fortified foods, and so do many lacto-ovo vegetarians. Also, all older people, regardless of type of diet, should consume supplemental vitamin B12.

2. Vegetarians need less calcium than meat-eaters.

There is evidence that a lower protein intake reduces calcium needs. But there is as yet no evidence that vegetarians have lower needs than meat eaters. High intakes of protein cause loss of calcium from bones, and vegetarians typically consume less protein than meat eaters. However, this is just one of many factors affecting calcium needs. Vegetarians may also have lower estrogen levels, which can have a negative impact on bone health. Studies of bone health--particularly those looking at the spine--show that people with low calcium intakes have poor bone health even when their diets are modest in protein. Until we have actual clinical studies showing that vegetarians can have healthy bones with lower calcium intakes, vegetarians need to strive to meet calcium recommendations. It is also important to note that diets too low in protein have been linked to poorer bone health.

3. Vegetarians need to eat special combinations of plant foods to meet protein needs.

It's understandable that this myth has such a strong hold on vegetarians since it is something that nutrition experts believed for a long time. Particular combinations of plant foods--specifically grains with legumes--boost the availability of protein from these foods. But newer understanding of protein nutrition shows that it isn't necessary to eat these food combinations at the same meal. The key to getting adequate protein is to eat a variety of foods throughout the day, including high-protein foods like legumes and soy products, and to meet calorie needs.

4. Vitamins from supplements aren't absorbed as well as from foods.

Most vitamins are absorbed quite well from vitamin pills. In some cases, supplements are absorbed at much higher rates than vitamins occurring naturally in foods. For example, folic acid supplements are absorbed more efficiently than folic acid from foods. Although most people can meet needs for folic acid from a variety of whole plant foods, fortified foods and supplements can be very important for people with high needs for this vitamin, like pregnant women. In older people, vitamin B12 is absorbed much better from pills and fortified foods than the B12 that occurs naturally in dairy products, eggs, and meat. Therefore, even older people who eat animal foods and have diets high in vitamin B12 are advised to use supplemental sources of this vitamin. Because we can't duplicate the many healthful components of plant foods in a pill, it is wise to look first to whole foods when planning a balanced diet. But when diets fall short or physiological function is compromised, making up the difference with supplements or fortified foods is fine.

5. You can tell whether your diet is adequate by listening to your body and noting how you feel.

Over the short term, it is actually possible to eat a very poor diet and feel fine. Symptoms of nutritional deficiency take time to develop. You could eat a diet that is just a little too low in a nutrient and it might take several months or years before you felt sick from the effects of that deficiency. Eating a diet that raises risk for chronic diseases like cancer and heart disease also would not necessarily make you feel bad in the short term. In some cases it is important to pay close attention to how your body feels. Attention to hunger signals, for example, can keep you from overeating. But to make sure your diet is balanced, adequate in nutrients, and rich in protective plant compounds, it is important to follow scientifically based guidelines.

6. Vegetarian diets are automatically low in fat.

Some people are attracted to vegetarian diets because of this belief, and others shun vegetarianism because of it. Vegetarian diets are generally lower in fat than diets that include meat but they are not necessarily "low-fat." Many vegetarians include higher fat foods like nuts, seeds, avocado, and soyfoods in their diet. Many also cook with vegetable oils. Some lacto-ovo vegetarians who use generous amounts of full-fat dairy foods can actually have diets that are too high in saturated fat. However, vegetarian diets are usually significantly lower in saturated fat. Reducing saturated fat is more important for health than reducing total fat. So it is possible, and probably preferable, to eat a vegetarian diet with moderate fat content. Including some fat in a healthful plant-based diet makes the diet more appealing for most people and increases the chances that new vegetarians will stick to their more healthful eating plan.

7. Eating a diet low in meat is just as healthful as a vegetarian diet.

A prudent diet that limits meat, cuts down on saturated fat, and includes generous amounts of fiber-rich plant foods, will produce some of the benefits of a vegetarian diet and is far more healthful than more traditional meat-based diets. But some research shows that vegetarian diets are more health-promoting than diets that contain just small amounts of meat. In studies at Loma Linda University in California, even those who were only occasional meat eaters were at significantly higher risk for fatal heart disease compared to people who never ate meat.8. Vegetarian diets lead to eating disorders in teen-age girls.

Some research shows that vegetarian diets are fairly common among girls with eating disorders. (See our article in the News You Can Use section in this issue.) This is because some girls with eating disorders use vegetarian diets as a way to disguise changes in their eating habits. Vegetarian diets do not in any way increase the risk that a girl with healthy eating habits will develop an eating disorder.

9. Vegetarians are naturally slim and they don't get chronic diseases like heart disease and cancer.

Some people believe that dietary changes can automatically eliminate their chance of getting a chronic disease. But while a healthful diet can greatly reduce risk for some diseases, other factors, including some that may be beyond our control, impact risk as well. In the case of heart disease, it is possible for most people to significantly reduce risk with appropriate diet and lifestyle. Cancer is more complex, however. While certain diet changes can reduce risk, perhaps significantly, we don't yet know how to eliminate risk completely for this disease. Vegetarians are less likely to get certain diseases, but some still do get them. Plant-based diets tend to be lower in calories than diets that contain meat, and are the best approach to weight control. But even for vegetarians, weight loss requires some attention to calorie intake and exercise. A vegetarian diet makes it easier to stay slim but is not a guarantee.

10. Vegetarian diets require a lot of time and cooking expertise.

The growing number of convenience products makes it very easy to plan and prepare vegetarian meals. If you enjoy cooking, there are plenty of opportunities to make delicious meals from scratch. But the use of products like canned and instant beans, soyfoods, veggie burgers, frozen meals, and packaged dinners means that healthy vegetarian meals can be prepared in just minutes.