Humans are omnivores, meaning that our systems are set up to digest a complex mix of plant and animal proteins, carbohydrates, fats, and other nutrients. While some of us choose not to eat meat or dairy or exclude other substances from our diets, many of us, myself included, eat pretty much everything. But for optimal performance when working out, it makes sense to pay close attention to the quality (and quantity) of food you eat so you'll achieve the highest level of personal fitness. When it comes to protein, try to cut back on red meat and dairy and add more legumes (beans and nuts), free-range poultry, eggs, and fish. Carbs such as whole grains will complement the protein in your diet, but if you're working out more than three times a week, you should also make sure you get other nutrients such as B-complex vitamins, chromium, and zinc, because you can lose these when you exercise. Although there seems to be no overall agreement by physicians and wellness experts, many do recommend a multivitamin once a day, just to make sure you're getting everything you need for energy, well being, and peak athletic performance. Women especially should make sure they get enough calcium and iron (I've been taking a women's multivitamin for years).