If you want your brain to perform, you have to keep it well fueled. Fueling your brain isn’t just about eating the nutrients that your brain uses for energy directly. You have to think about the performance of your brain in the context of the performance of your body as a whole, and eat, exercise, and live in a way that allows you to get the most out of brain and body.

Fueling Your Brain Principles:

1. Know your brain foods

Your brain can only run off of two things: Sugar and an amino acid called Glutamine. Glutamine generally provides less than 1% of the energy used by your brain, so we’ll focus on sugar. The key to keeping your brain fueled with sugar is to maintain stable levels of blood sugar. Food and Mood and Nutrition, Energy, and Mood discuss the way that blood sugar levels influence how we feel. In essence, unstable blood sugar leads to energy crashes and worsened mood. Blood sugar is just as important to the performance of your brain as it is to your emotions.  Without adequate blood sugar, you simply cannot think effectively. Memory, creativity, problem solving, language – every aspect of mental performance is dependent on blood sugar levels. In breif, the best ways to maintain stable blood sugar are to eat reasonable portions, eat balanced meals containing fat, protein, fiber, and "low glycemic" carbs, and, above all, to avoid eating sugar. The principles in Simple Enjoyable Healthy Eating, in addition to Food and Mood and Nutrition, Energy, and Mood offer a lot more detail, and should provide all the advice you need on maintaining stable blood sugar.

2. Body Supports Brain

You cannot maintain a healthy, happy, optimally functioning brain without a healthy body. Every cell in your brain depends on a constant flow of nutrients, water, and oxygen provided by the body. An unhealthy body can’t deliver these things as effectively. There are loads of changes you can make in your physical health habits (in addition to eating better) that will improve the performance of your brain. Once of the simplest of these is to change the way you breathe. 

Poor breathing technique, which is exacerbated by bad posture (see Muscle Balance, Alignment, and Posture) results in less oxygenated blood. The brain is starved for oxygen just as is the body, and with lower oxygen levels, mental performance deteriorates. Try this experiment. The next time you're feeling tired in a meeting or a class, sit up straight and breath deeply into your stomach for a few minutes (read our Breathing Tutorial for more advice on breathing technique). As you start to oxygenate your blood more effectively, you’ll wake up and find it easier to pay attention.

Another great way to wake up your brain is to exercise. Exercise mobilizes energy stores in the body, and since the same blood supply feeds both body and brain, the brain receives more energy as well. Over time, regular exercise results in consistently higher physical and mental energy levels, leaving you more alert and focused even on days when you don't exercise. Even two weeks of exercise is enough to begin improving mental performance in addition to physical health.