Strictly speaking, there isn't such a thing as a yogic diet. There are no nutrition guidelines in the traditional yoga scriptures. So you won't find exact guidelines in this text, just some ideas how you can upgrade your eating habits to reflect your yoga practice.
First, let's look at some traditional points of view on various foods and their effects.
In the Ayurvedic tradition, foods that are beneficial to the body and mind are called Sattvic, or pure. Sattvic foods are light but nourishing and easy to digest. They make us feel happy, energetic and calm, which also enhances our mental and physical abilities. Sattvic foods include cereal, fruit and vegetables, milk, butter, cream, yoghurt, nuts, seeds, lentils, rice, grains and honey.
Rajasic, or stimulating foods are spicy and salty. They are believed to be able to make you agitated and restless. You may experience emotional imbalance if you eat too much rajasic food.
Tamasic, or stale foods are heavy and cause a distracted mind. When overeaten, they may make you feel sleepy and depressed. These foods include red meat, onions, garlic and others.
Doesn't it seem similar to healthy nutrition rules? Eat lots of fruit and vegetables, beans and legumes, dairy, seeds and nuts and go easy on meats and fats? Exactly.
Some more yogic-eating ideas: favor raw and fresh foods, reduce the amount of sugar and alcohol, choose local-grown and seasonal produce, eat a little less than you need to feel full, but not too little.
Most modern yoga experts agree that you should listen to your body when trying to change your eating habits. There is no point in going vegan when you feel that your body needs some meat every now and then just to function properly. You can tell that you're eating the right way when it makes you feel happy and balanced. Experiment and you're sure to find what's yours.