The percentage of diet that should be made up of barley, gram, maize, and millets can vary depending on individual dietary needs and preferences. However, in general, a healthy and balanced diet should include a variety of whole grains, including barley, gram (also known as chickpeas), maize (also known as corn), and millets. According to the USDA's MyPlate guidelines, whole grains should make up at least half of your daily grain intake. This can be achieved by choosing whole grain versions of foods like bread, pasta, and rice, and by incorporating other whole grains like barley, gram, maize, and millets into your meals.
Aim to include a variety of whole grains in your diet, rather than relying on just one or two. For example, you could have barley in a salad, gram in a curry, maize in a soup, and millet in a breakfast porridge. This can help ensure that you're getting a range of nutrients from different sources. Remember to also balance your grain intake with other food groups like fruits, vegetables, protein, and healthy fats to create a well-rounded and balanced diet.