Making progress on the global crisis of obesity and weight managementBMJ 2018; 361 doi: https://doi.org/10.1136/bmj.k2538 (Published 13 June 2018) Cite this as: BMJ 2018;361:k2538
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As highly desirable as the political and legislative changes that Lean et al (1) propose to reduce the obesogenic environment may be, it is probably unrealistic to expect a reversal of national obesity trends without those changes. Thus, for the foreseeable future, in the UK obesity prevention will ultimately remain devolved down to individuals.
Arguably, a large part of the population is unprepared for this role. The proverbial kid in a sweetshop, confused by mixture of dietary messages and limited only by the money in their pocket to act as a restraint on food purchasing behaviour is perhaps an apt stereotype.
Unfortunately, the consequences of the macroeconomic financial environment with insufficient funding and lack of appropriately trained personnel means that individual “willpower” based weight management and control will continue to be the mainstay of primary care.
However, as Lean et al (1) allude, most individuals are unable to mobilise appropriate psychophysiological building blocks to achieve a sufficient state of self-control that allows them to improve their ability to cope with exposure to the obesogenic environment.
There is, however, some tentative data that some of those building blocks or inner resources that may contribute to making better dietary choices can be developed.
Techniques such as working memory training, (2) mental imagery and meditation (3), hypnosis (4) may be useful in the development of internal resources for managing weight.
In the more hypnotisable, hypnosis may help reduce the desirability of unhealthy snack foods. The altered desirability is associated with BOLD changes in the ventro-medial Prefrontal Cortex (vmPFC) (5).
Krushwitz et al (6) have recently demonstrated that a positive view of the future, for example, being healthier in relation to making better food choices can activate stronger connectivity between areas of the brain such as the vmPFC, dorsal posterior cingular cortex and ventral striatum. These areas are linked with positive affect processing as well as with the default mode network.
The study by Bo et al (4) has shown that the success of positively framed hypnosis seems to be in the form of a dose response relationship. Those who habitually practice self-hypnosis most intensively lose the most weight over the course of a year. The adage of practice makes perfect would seem to apply to wilful-power of hypnosis for losing weight!
1) Lean MEJ, Astrup A, Roberts SB Making progress on the global crisis of obesity and weight management. BMJ. 2018 Jun 13;361:k2538. doi: 10.1136/bmj.k2538.
2) Houben K, Dassen FC, Jansen A, Taking control: Working memory training in overweight individuals increases self-regulation of food intake. Appetite. 2016 Oct 1;105:567-74. doi: 10.1016/j.appet.2016.06.029. Epub 2016 Jun 25.
3) Missbach B, Florack A and König J (2015) Mental imagery and food consumption. Front. Psychia- try 6:48. doi: 10.3389/fpsyt.2015.00048
4) Bo S, Rahimi F, Goitre I et al Effects of Self-Conditioning Techniques (Self-Hypnosis) in Promoting Weight Loss in Patients with Severe Obesity: A Randomized Controlled Trial. Obesity (2018) 26, 1422-1429. doi:10.1002/oby.22262
5) Ludwig VU, Stelzel C, Krutiak H et al. The suggestible brain: posthypnotic effects on value-based decision-making. Soc Cogn Affect Neurosci. 2014 Sep;9(9):1281-8. doi: 10.1093/scan/nst110. Epub 2013 Jul 24.
6) Kruschwitz JD, Ludwig VU, Waller L, List D, Wisniewski D, Wolfensteller U, Goschke T and Walter H (2018) Regulating Craving by Anticipating Positive and Negative Outcomes: A Multivariate Pattern Analysis and Network Connectivity Approach. Front. Behav. Neurosci. 12:297. doi: 10.3389/fnbeh.2018.00297
Competing interests: No competing interests
Lean and colleagues article (1) on obesity fails to give sufficient acknowledgement to the role of palatability and phenotypic plasticity in the current obesity epidemic.
The high palatability of modern processed foods, to a large extent, is the consequence of added sugar (2,3). For example, fats and oils are relatively unpalatable but the addition of a small amount of sugar gives rise to a substantial increase in hedonic preference ratings (2) and therefore the likelihood of overconsumption.
Epigenetic transgenerational inheritance plays a role in evolutionary change (4,5,6) and is almost certainly a factor behind the apparent evolution of modern man in to a fatter “species” and obesity’s resistance to “treatment”.
The greatly enhanced palatability of the modern food environment is a significant environmental change and some behaviours of the obese appear to be adaptive to this new environment. For example, the obese have a lower preference for sweetness (7), under respond to food deprivation (8) and are more likely to skip meals (9). A recent study indicates that future generations also exposed to this obesogenic nutritional environment may have a lower risk of metabolic disorders also due to epigenetic adaptations (10).
I agree that the current epidemic will only be curtailed by regulation and taxation of the food environment but as epigenetic changes can persist through generations significant beneficial change may take more than one generation.
1. Lean M, Astrup A, Roberts S. Making progress on the global crisis of obesity and weight management. BMJ 2018;361:k2538.
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3. Bradley PJ. Pathophysiology of Obesity. Lancet 1992;340:848.
4. Skinner MK, Gurerrero-Bosagna C, Haque MM, Nilsson EE, Koop JAH, Knutie SA Clayton DH. Epigenetics and the Evolution of Darwin’s Finches. Genome Biol. Evol. 2014;6(8):1972-1989.
5. Osborne A. The role of epigenetics in human evolution. Bioscience Horizons 2017;10:1-8.
6. Price T, Qvarnstrom A, Irwin DE. The role of phenotypic plasticity in driving genetic evolution. Proc Biol Sci 2003;270(1523):1433-1440.
7. Drewnowski A, Brunzel JD, Sande K, Iverius PH, Greenwood MRC. Sweet Tooth Reconsidered: Taste Responsiveness in Human Obesity. Physiol Behav 1985;35:617-622.
8. Wooley OW, Wooley SC, Dunham RB. Deprivation, expectation and threat: Effects on salivation in obese and nonobese. Physiol Behav 1976;17(2):187-93.
9. Mota J, Fidalgo F, Silva R, Ribeiro JC, Santos R, Carvalho J, Santos MP. Relationship between physical activity, obesity and meal frequency in adolescents. Ann Hum Behav 2008;35(1):1-10.
10. Tait AH, Raubenheimer D, Green MP, Cupido CL, Gluckman PD, Vickers MH. Successive Generations in a Rat Model Respond Differently to a Constant Obesogenic Environment. PLoS ONE 2015;10(7):e0129779.
Competing interests: No competing interests