It's often said that good health is the foundation of beauty. I'm willing to take that statement a step farther and claim that a balanced diet is the foundation of good health - and, therefore, beauty. For proof, just read the numerous medical studies that link healthy eating with disease prevention and disease reversal. These same studies connect high fat intake, high sodium consumption, and diets with too much protein to numerous illnesses, including obesity, cancer, cardiovascular diseases, diverticular diseases, hypertension, and kidney disease. And of course, there are all the looks-stealing side effects of a poor diet, such as thinning hair, scaly skin, breakouts, pale complexion, nail disorders, and excess weight. A nutrient-weak diet can also exacerbate existing skin conditions such as psoriasis and rosacea.

There are all kinds of health reasons to curb your salt intake to the recommended limit of 500 mg per day. For those prone to breakouts, iodine - a mineral found in iodized salt and seafood ­ is believed by many professionals to contribute to acne flare-ups.

But what exactly is a balanced diet? Generally speaking, it is a diet comprising carbohydrates, dietary fiber, fat, protein, water, 13 vitamins, and 20 minerals. More specifically, it is a diet built around a wide variety of fruits, legumes, whole grains, and vegetables. Animal protein, high-fat foods, high-sodium foods, highly sugared foods, sodas, and processed foods are consumed sparingly, if at all. Of course, there are several ways to get your daily allotment of nutrients. Here are several of the most common diets.

All about omnivores

How healthy is an omnivorous diet? It depends. Omnivores may eat cheese, eggs, meat, poultry, fish, or seafood every day, choose refined snacks, and get only one daily serving of fruits and vegetables. This is not the healthiest option for those on an omnivorous diet.

On the other hand, those omnivores who limit animal-based foods to two or three times a week, choose water over soft drinks, and get the recommended five or more daily servings of fruits and vegetables have a much healthier diet. The usual complaints about traditional omnivorous diets revolve around the diet's high levels of cholesterol and saturated fat (found in animal-based foods), which can increase the risk of cancer diabetes, heart disease, and obesity. However, an omnivorous diet can actually be a healthy one, provided that thoughtful choices are made. To keep cholesterol and saturated fat to a minimum and nutrients to a maximum, omnivores should aim to eat five or more daily servings of fruits and vegetables, choose whole grains over refined grains, enjoy daily legume or soy food protein sources, and limit their consumption of animal-based foods.