Baumeister’s thesis, borne out by extensive experimental data, is that willpower – the force by which we control and manage our thoughts, impulses and emotions and which helps us persevere with difficult tasks – is actually rather like a kind of moral muscle. He postulates that we have a finite amount of willpower and if we exercise restraint or control in one area of our life we have less available to bring to bear in other areas of our life. Put simply, the more conscious willpower we have to exert each day, the less energy we have left over to resist our brain’s primitive and powerful pull to instant gratification. Willpower depends on physical energy and it turns out it especially depends on glucose. Acts of willpower draw on our body’s glucose reserves and when our glucose levels are low – our willpower is also depleted. Like a muscle, rest, sleep and the right nutrition will restore our energy levels and our willpower.
Baumeister’s research has significant implications for anybody trying to change their behaviour, but particularly changing behaviour that involves the self-restraint that is required to lose weight. Let’s return to John.
To understand John’s struggle we have to understand his ‘appetite’ and eating behaviours. As a child he was encouraged to clear his plate and to eat more when it was available. His parents wanted him to grow up to be a ‘big strong boy.’ So, clearing his plate and eating more brought the emotional reward of his parent’s approval and this behaviour became internalised and unconscious. John also had a demanding job that required him to make key decisions throughout his day. In this sense he was constantly asserting his willpower. When it came to eating, particularly an evening meal, he had no reserve of willpower to draw on and the unconscious eating behaviour kicked in.
This is where it gets interesting as Baumeister’s research presents a paradox for dieters. In order to summon up the willpower not to eat, they need to eat something to replenish their glucose levels!
In Part 3, I will explore what we can do to strengthening willpower in order to turn our intention into the behaviour we want.
Written by Dr. Noel Duncan
Roy F. Baumeister & John Tierney (2011), Willpower: Rediscovering Our greatest Strength.