BY DR JANE OGDEN, PROFESSOR IN HEALTH PSYCHOLOGY
Being overweight is clearly bad for our physical and mental health. Yet losing weight is hard and the majority of people who lose weight put it back on. This paper will describe the benefits of weight loss, why diets fails and then will explore the lessons to be learnt from those who are successful in longer term weight loss maintenance.
The benefits of weight loss
For those who are overweight or obese even 10% weight loss causes a dramatic reduction in the risk of heart disease and stroke, the risk of weight related cancers such as breast cancer and endometrial cancer in women and the reversal of type 2 Diabetes. Losing weight can also improve life expectancy as long as this weight loss is sustained. Further, weight also reduces symptoms
such as breathlessness, back and knee pain and the susceptibility to minor infections and also increases self esteem, confidence and mood. Unfortunately although the majority of people who diet manage to lose weight initially, many show weight regain by 5 years follow up. Temporary weight loss may have some benefits but some research suggests that yoyo dieting (ie showing large fluctuations in weight) may be harmful, and even more harmful than remaining at a more stable higher weight. It would be a shame if this deterred people from trying to lose weight but it does indicate the negative side of failed dieting. It also highlights how important it is to diet in a way that can be sustained for the longer term.
Why diets fail
Eating and exercise are a product of what’s in our heads and triggers in our environment. Dieting therefore involves managing these factors. Yet many diets fail habits are hard to change. This is again due to how habits are formed and what’s in our heads and the triggers in the world around us.
How habits are formed
Habits are formed through four very simple processes: modelling, repetition, reinforcement and association. We often carry out a behavior because we see other people doing it. Then when we repeat a behaviour several times it becomes a pattern. It then becomes a habit if it reinforced by something positive such as we like it, someone else likes us doing it and it makes us
feel good. This is even true for ‘bad habits’ as these also make us feel good at some level. Then it becomes a strong habit if it becomes associated with something in our environment or our mood. So take breakfast. Lots of people don’t like breakfast as they are ‘too tired’, ‘it makes me feel sick’ or ‘I just can’t eat in the morning’. This is because their normal behaviour is not to eat and eating first thing in the morning feels strange. But then if someone eats breakfast in front of them and can get them to eat breakfast every morning for a couple of weeks, a new pattern will soon be set (repetition). They will start to like the feeling of being more alert and spending a few minutes each morning sat quietly eating breakfast (reinforcement) and this new behaviour will be triggered by seeing the fridge, smelling someone else’s toast or simply getting out of bed (association). Then, not eating breakfast will start to feel strange as their new normal behaviour has been established.
So why are habits difficult to change?
Habits are difficult to change as ultimately at the moment of doing any behaviour its benefits outweigh the costs. So although eating cake may add to your weight problem, at the time of eating cake, the pleasure of its taste and texture cancel out the fear of having a heart attack when you are 60. Habits are therefore the result of a simple cost / benefit analysis, and mostly, we are hopeless at thinking about the future, so that the immediate benefits pretty much always outweigh the future costs. This process is facilitated by a number of different factors as follows which are either in our heads or in the environment.
What’s in our heads
There are many factors inside our heads that make habits hard to change as follows:
Some triggers such as the fizzy drink aisle at the supermarket can be avoided. But those triggers in our heads such as our mood (such as feeling fed up) are very difficult to avoid as they follow us everywhere and are hard to ignore.
Withdrawal and feelings of worry and stress:
Habits are part of our everyday lives and therefore when we don’t clean our teeth, eat breakfast, have our morning coffee or have biscuits in the afternoon we feel unsettled and a little bit stressed. This feeling is unpleasant and we quickly learn that it can be avoided by carrying on with our habit. So we eat more to undo the unpleasant feeling of having eaten less.
Denial and rebound effects:
Not doing something often makes us want to do it more and leads to rebound effects. So if we say to ourselves ‘today I will not eat cake’ automatically we think about cake more, not less. Then, because we are thinking about cake more, but can’t have it, we want it more as the day progresses. Eventually when we give in and have cake, not only do we now want it more than we did in the morning, we end up eating more cake because we have been denying ourselves all day. We call this ‘the what the hell effect’.
Beliefs about food preferences:
People often believe food preferences are biological and set from when we are born. They aren’t – they are learned from our culture, family and peers. But if we believe that we inherently just don’t like certain healthier foods then a diet will be hard to follow. And the new healthier habits will be harder to set up.
Triggers in the environment
Triggers in our environment also undermine any attempt to change our eating and exercise habits.
Some environmental triggers are physical such as the biscuit tin, the fridge, carefully placed snack foods in supermarkets or the cake trolley at work which cause mindless shopping and mindless eating. These can prompt unhealthy behavior.
People like us to carry on the way we always have done as it makes them feel safe. If we change, then they feel that they have to change and that is unsettling. So the social pressure always increases to maintain the status quo whenever anyone tries to break a habit.
Losing weight is therefore hard and often undermined by what’s in our heads and the triggers in our environment. But sometimes, diets work! Here are some lessons we can learn from those who have managed to lose weight and keep it off.
Although dieting is hard some people do succeed. Research has taken three different approaches to explore why some people manage to lose weight and keep it off. First, some studies have identified success stories and used qualitative methods to explore how these people have managed to show weight loss maintenance. Second, other studies have used quantitative methods to compare those who have been successful to those who have been less successful. Finally, some studies have taken the data from large scale interventions to explore what factors predict weight loss maintenance in the longer term. These studies can be combined to tell us about how successful dieting can be achieved suggest that weight loss which lasts into the longer term is a result of the follow steps.
A life event:
Successful dieting is often triggered by a life event or medical trigger which shakes up the person’s world and offers a chance for change. This can be a diagnosis of diabetes or cancer, being unable to get up stairs or carry your children and simply turning ‘40’ or seeing a photo of yourself.
Believing things can change:
Many people believe that their weight is a product of biology or their genetics which cannot be changed. But if a person holds a more behavioural model of their weight problem and has hope that things can change this makes initial change more likely. Therefore they need to recognize that weight is a product of what they eat and how active they are.
A shift in the cost / benefit analysis:
Eating cake now always outweighs a heart attacks in 20 years time and immediate benefits always outweigh future costs. People therefore need to be able to identify immediate benefits of eating well and being more active which outweigh the immediate costs of these new behaviours. Successful dieting is therefore linked to a shift in the cost benefit analysis of health behaviours which can be brought around through strategies such as goal setting, self weighing, contact with a formal intervention or dietician. This will not enable healthier behaviours to have greater benefits but also bring these benefits into the here and now making them more sustainable.
Changing behavior and being healthier takes time, effort, energy, sometimes money and sometimes impacts upon those around us. This reflects a certain degree of investment
. Successful dieters need not only to have made an initial investment in change and also to focus on this investment and be aware of how much investment they have already made. This gives momentum to their success and makes it less likely that they will slip back.
A new behavior regimen:
In turn this all then culminates in a new consistent behaviour regimen and evidence suggests that eating breakfast, having regular mealtimes, practicing healthy eating and a reduced intake of fat together with increased physical activity are the most effective ways to lose weight.
people need to feel in control of their behavior in order to change habits for the longer term. This renewed sense of control can be created through self monitoring and illustrated by improved dieting and reduced overeating.
A new identity:
Finally, successful dieting also seems to be achieved through the development of a new identity and a process of reinvention at the centre of which is a healthier thinner self. This way people are no longer just their older unhealthy version of themselves waiting to slip back but can reinvent themselves in ways that helps them continue being healthy into the future.
Weight loss can therefore with it many physical and psychological benefits including a reducation in the risk of chronic conditions and an improved sense of well being. But weight loss involves eating less and doing more which is hard as habits are often entrenched and difficult to change. This chapter has described why habits are hard to changed and outlines some of
the lessons that can be learned from those who have successfully lost weight and kept it off. The trick, however, is not to not only know what makes someone successful but to help make this happen. This is the focus of paper 3 on ‘Making weight loss happen’.
Ogden, J. (2018). The Psychology of Dieting. Routledge: UK
Written by ACA Contributor Dr Jane Ogden BSc, PhD, CPsychol
Jane Ogden is a Professor in Health Psychology at the University of Surrey where she teaches psychology, vet, nutrition, dietician and medical students to think more psychologically about health. Her main research areas are eating behaviour, obesity management and parenting around food. She has published 7 books including ‘The Psychology of Eating’; The Good Parenting Food Guide’ and ‘The Psychology of Dieting’ (due out Jan 2018) and over 180 research papers. She is a regular contributor to the media in terms of radio, TV, social media, magazines and newspapers and is passionate about making research accessible for a lay audience.