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Eliminating the Stress of Dieting

Understanding the psychology of dieting can lead to more satisfying outcomes.

Key points

  • Following a diet is an example of following an extrinsic (external) motivator, which predicts eventual lack of compliance or follow-through.
  • Deci and Ryan’s Self-Determination Theory has spelled out three psychological needs that must be met for lasting behavior change to occur.
  • Weight loss plans that promote autonomy, competence, and social relatedness predict persistence and positive outcomes.
Vadym Petrochenko/iStock
Source: Vadym Petrochenko/iStock

Most people who have gone on a diet can tell you that they soon give up. It is just too difficult to stay motivated, stay with the program, and feel deprived day after day. The weight eventually comes back on.

Spelling Out the Problem

Looking at the big picture of what goes on with dieting, it becomes apparent that most diets are programs that are imposed upon us. Often, the premise is that you have been eating the "wrong" way, and you need to follow a program in order to get the pounds off. You are not given the chance to figure this out on your own.

So, when a diet plan is being followed, the implications can be far-reaching and deep. Following a diet plan thus keeps you as a victim—someone with no power over what or how they eat.

Perhaps there is an initial motivation to stick with a diet because it feels like it will help get some pounds off. After all, that is the intended goal. You can tell yourself that you have a goal and the motivation, and that is good. Following a diet seems like the obvious solution.

But by following a diet, you are using an extrinsic motivator. An extrinsic (or external) motivator is something that is laid on you by others and does not come from within.

The person using an external motivator may be thinking that following directions will be easier than having to come up with more nuanced or complex solutions. In fact, it may be that they are not even aware of any other solutions.

But there are some problems with using the external motivator that is a diet. One large problem is that when a diet is imposed, it is easy to slide into a mentality of punishment (deprivation) or rewards (cheat days). It becomes compliance vs. rebellion.

In addition, a diet often comes along with a “should” mentality. The dieter follows along, and not necessarily willingly. It’s a matter of giving it a try because others have said you should.

And one more thing: Following a diet plan may seem to the follower that it is a way to reduce the stress of having to make food choices, day in and day out. But this way of thinking can easily backfire.

What’s Going On Beneath the Surface

We humans are complex. According to multiple avenues of research, we have certain psychological needs that are with us all the time. In order to be masters of our own fates (like how to eat in order to lose weight), these needs must be met.

The needs are spelled out in Deci and Ryan’s Self-Determination Theory of behavior change. Briefly, they are (1) the need for autonomy, (2) the need for competence and mastery, and (3) the need for relatedness, or support and connectedness with others.

How Does This Relate to Losing Weight and Keeping It Off?

When we intend to lose weight and set a goal to do that, the way we set out to do that can lead to an effective solution or a frustrating failure.

Deci and others have verified in research that a goal-oriented process that supports the psychological needs spelled out in Self-Determination Theory will lead to success. When outside (extrinsic) forces are applied, none of the three psychological needs are being met, making it very difficult to reach personal goals.

When autonomy, competence, and relatedness are developed, research has shown that persistence and positive outcomes ensue. When they are not, one can predict an eventual lack of compliance or follow-through toward the end goal.

Deci also proposes three ways to foster self-determination and autonomy. (1) The person needs to become aware of their personal rationale (a bottom line “why” that is very compelling for that person), (2) letting the person develop their own choices that will lead to goal attainment, and (3) learning to acknowledge and deal with their own unique barriers and conflicts.

When it comes to losing weight, it is often suggested that individuals set SMART goals to help them. SMART is the acronym used for:

  • Specific
  • Measurable
  • Attainable
  • Realistic
  • Timely

This type of goal setting covers a lot of bases in the context of self-determination. Being very specific and concrete about a goal that is chosen by the individual to be tailored to their situation can go a long way toward building autonomy.

But what’s missing here are three things.

  • Homing in on the over-arching “why” or rationale for the desired change. It is important to have a compelling “why” to be referred to again and again during the process.
  • It is also useful to have a guiding structure for making a series of SMART goal choices over time that will be in keeping with a goal to lose weight.
  • Finally, guidance may be needed in order to learn techniques that will lead to the attainment of each SMART goal. Many individuals may need help using mindfulness, self-talk, affirmations, and developing self-awareness of current attitudes and barriers.

The problem is complex! We need to chip away at it by creating awareness of how to develop autonomy, mastery, and personal empowerment over every aspect of the solution.


Deci, E.L., and Ryan, R.M. (2000). The “What” and “Why” of Goal Pursuits: Human Needs and the Self-Determination of Behavior. Psychological Inquiry, 11 (4), 227-268.

Deci, E.L., Eghrari, H, Patrick, B.C., Leone, D.R. (1994). Facilitating Internalization: The Self-Determination Theory Perspective. Journal of Personality, 62, (1), 119-142

Silva, M.N. et al. (2009). Using self-determination theory to promote physical activity and weight control: a randomized controlled trial in women. Journal of Behavioral Medicine, 33, 110-122.

Williams, G.C. et al. (1996). Motivational predictors of weight loss and weight-loss maintenance. Journal of Personality and Social Psychology, 70(1), 115-126.