Brain Power Part II

Last time I ranted all about physical activity and the brain; now I want to focus more on what people put in their bodies and how it affects the brain and what kinds/how many of these nutrients people need to keep their brains running.  Or thinking. 

Meredith sings to my moderation song when she says that it is not necessary to eat any special foods to enhance brain power, but mainly to eat a balanced diet.  For the facts I use in this post to both support and refute Meredith, I cite an article from Scientific American by Jerris Fabr from 2012. Meredith and Fabr both agree that the “brain worker” (in Meredith’s words) needs little more food than if he were to have "one very lazy day of no activity" (in Fabr's words). The brain already requires a huge amount of blood, oxygen, and nutrients (mainly glucose) to function, and extra mental effort (ie thinking) requires little more energy consumption than this already huge baseline.  According to Fabr, the brain, which only weights 2% of our body weight (on average) requires about 20% of our resting metabolic rate (RMR) which is the total energy our bodies expend even if we are just sitting on our tush playing video games (in my words). In an average human, this is about 1,300 calories. Awesome right? We burn calories even when we’re not doing ANYTHING.

So, what should we put into our bodies exactly to keep this giant energy and calorie suck functioning?

Meredith says that “clinically it is evident that if a faulty diet (or other causes) lowers the percentage of sugar in the blood the brain is impaired in its functions.” However, according to Fabr, it really isn’t as simple as direct logic of if A then B, in regards to putting sugar into our brain and therefore having it function properly and efficiently.  Working harder and using more glucose before expending more than normal brain energy or mental effort may not actually impair brain function. In one study cited, it is noted that the brain requires so much baseline energy and is constantly maintaining a complicated balance of nutrients and neuronal maintenance, that the brain has enough energy already to add a little extra work (even if that work is in the form of your really really really dense philosophy reading).

Relating this to the workout ideas from the previous post, one study showed that children who walked for 20 minutes on a treadmill performed better on an academic achievement test compared to children who read quietly before the exam.  I wont get into the physical benefits of the workout for the treadmill group, but in terms of glucose, the children walking were using more energy, and therefore burning more glucose, so if mental ability was a matter of increased vs. decreased glucose, the children who expended more energy before the test should have performed worse. Although individual differences are obviously a factor, the simple idea that more or less available glucose affects mental effort is not necessarily correct.

Physical symptoms, however can affect our ability and efficiency in studying. A huge part of mental exhaustion and fatigue, especially during taking important, stressful tests, like the SAT, is caused by physical stress (measured by increased cortisol and heart rate). Diet also physically affects mental ability, and if one were to eat a diet that makes him or her physically feel unwell (like if you had a stomach ache from eating bad chicken tenders), or does not contain proper nutrients (you only eat potatoes), this will surely affect concentration and focus, if not in the short term, than in the long term. 

If you are hungry (or tired, or have any other form of physical ailment) while trying to study, you wont be able to study as efficiently. This is probably not only due to lack of nutrition or proper health, but distraction. Sometimes, it really is just a mental thing: you are distracted by paying attention, focusing mental effort, fixating, etc. on your physical symptoms rather than the homework in front of you.  Or, you are simply looking for an excuse not to continue studying. Being more aware of your grumbling tummy or closing eye lids is probably why you can't study, rather than your brain being completely depleted of nutrients and physically unable to carry on. Because if that were you case, you would probably be dead.

In terms of food, one of my favorite topics is “brain foods.” Fish is brain food! Eating nuts will help you think better. Avocados will make you a genius! Well...not really.  These claims mainly exist because these foods have nutrients that the body and brain need to continue normal functioning.  Although food obviously affects and plays an important role in body functions, including brain functions, don’t expect that eating walnuts, olive oil, berries, fish, coffee, leafy greens, avocadoes, chocolate, and garlic (according to the Huffington Post) will make you smarter or able to concentrate way better than normal.  Basically, these foods contain omega-3 fatty acids (“good fat”), antioxidants, zinc, vitamin E, and a whole host of other nutrients that are important for all types of body functioning.  

What you should really do is eat in moderation; make sure these foods are a part of your healthy, balanced, and nutritious diet most of the time, and I think you’ll be okay.  In other words, making a walnut, avocado, and spinach sandwich, washing it down with a latte and expecting to turn into a super-dee-duper braniac is not really how it works.