There is no shortage of advice available on what we should and should not eat, yet many people remain confused about what constitutes a truly healthy diet. (0) OVER the past few decades, nutritional science has undergone significant changes, and recommendations that were once considered reliable have since been called 1 question. Fat, for example, was long thought to 2 the main cause of weight gain and heart disease, but more recent studies suggest that not all fats are harmful. 3 fact, some types of fat, such as those found in nuts and olive oil, are now believed to be beneficial for overall health. Similarly, the role of carbohydrates has been hotly debated, 4 some experts arguing that a low-carbohydrate diet is the most effective way to lose weight. Others, 5, point out that carbohydrates are the body's primary source of energy and should not be eliminated entirely. One thing most nutritionists agree 6 is that a balanced diet — one that includes a variety of foods in appropriate quantities — is far more important than following any single trend. The problem is that the sheer volume of conflicting information makes it difficult for ordinary people to know 7 advice to trust. Until a clearer consensus emerges, the best approach may simply be to eat a wide range of whole foods and to avoid processed products 8 much as possible.