"Some of the early studies coming out a few years ago suggested that when we exert willpower, it uses so much more energy in the brain than our typical tasks you can see a drop in circulating blood glucose levels...which suggest that the brain is using a real source of energy – or your brain is using up energy--in order to resist temptation or to focus your attention.
One of the ideas that came out of some of this research: willpower is
depletable. It’s so easily depletable that you get a temporary drop in your
willpower reserve each time you use your willpower. Now, some of the studies
that have come out more recently are suggesting that the relationship between
blood sugar and willpower is a little bit more complicated
than just thinking, Well, I’m going to mainline sugar to make sure I’ve got
lots of energy so that my brain won’t get tired, which is how some of this
got interpreted initially.
It seems that the brain monitors fluctuations in
blood glucose, and what your brain likes is a steady state of blood glucose. If
the brain feels comfortable that you have a steady state of energy, it is comfortable
using the energy required to control impulses or focus your attention. The
brain doesn’t like big spikes and drops in blood sugar.
There’s some interesting
research suggesting that your brain gets kind of stingy when it doesn’t trust a
stable energy supply, so it will be reluctant to use systems of the brain that
require more energy. With this more evolved way of thinking about the
relationship between sugar and willpower, the best thing you can do is eat a
diet that gives you a steady supply of blood sugar.
My students, when
they heard the original studies, were thinking, Great,I’ll just eat candy
before I need willpower, which of course is not going to make your brain
feel very good about its stable blood sugar supply. It seems to be pretty
important to eat on a regular basis and eat the kind of diet that’s going to
give us a steady state of energy levels that help us be our best selves with
the best kind of willpower reserve." Dr McGonigal starts the lecture by reminding us that willpower is controlled by the prefrontal cortex and helps us control that mid-brain where emotions tell us to seek gratification and avoid pain right now. Our willpower is part of our logical brain. There is a brain-gut connection once again with how efficiently our brain functions and our diet. The research Dr. McGonigal cites above goes along with the idea that mood follows blood glucose: when you eat foods that help you stabilize and balance blood glucose, like whole foods, you are able to stabilize and balance your prefrontal cortex's ability to manage that emotional brain.
What foods stabilize blood glucose again? That's right, whole foods! Protein, complex carbohydrates, and unprocessed, uncorrupted food. Eat food as close to the way God created it in the first place.
