Institute of Global Health Innovation

By Nicholas Penney, Clinical Research Fellow, Osama Moussa, Clinical Research and Surgical Fellow and Sanjay Purkayastha, Clinical Senior Lecturer in Bariatric Surgery at the Faculty of Medicine, Department of Surgery & Cancer, Imperial College London

Obesity is a worldwide epidemic and leading preventable cause of death, with increasing rates in both adults and children. Between 1980 and 2008, global obesity prevalence doubled from 4.8% to 9.8% in men and from 7.9% to 13.8% in women¹. In 2014, more than 1.9 billion adults were overweight, of which over 600 million were obese².

Obesity leads to multiple significant comorbidities, including diabetes, cardiovascular disease, and cancer. This is without doubt profoundly important for the affected obese individuals, but in addition the associated morbidity is hugely economically damaging for society. Urgent action is needed to prevent this growing trend.

These increases in obesity have been largely driven by rapid urbanisation and economic growth coupled with trade liberalisation. This has led to increased accessibility of refined grains and sugars at lower costs. Furthermore, this has coincided with technological advances and increased mechanisation leading to reduced physical activity³.

The solution to the problem requires a consistent reduction in calorie intake and increased energy expenditure. Establishing these changes is of course highly complex. It is likely to require multiple interventions and changes to government policy, societal attitudes, available help through the NHS and personal choices.

As a recent example of governmental intervention, the Soft Drinks Industry Levy or “sugar tax” due to be introduced of course raises awareness of the dangers of sugar and may lead to a reduction in intake. However, Professor Winkler recently highlighted that “a 10% tax would reduce average personal daily intake by 7.5 mL, less than a sip… a 20% tax would reduce consumption by 4 kcal. Effects of this size will not reverse global obesity.” Clearly further interventions will be required to significantly alter eating behaviors.

Help is currently offered in the NHS through multi-component lifestyle interventions. These programmes include advice on dieting and increasing physical activity and address patient’s psycho-social requirements. Unfortunately the majority of patients fail to lose significant levels of weight despite these programmes and furthermore any weight loss is often not sustained.

At the Imperial Weight Centre, we have a high level of experience of patients who have failed to lose weight through lifestyle intervention that go on to undergo bariatric surgery. Bariatric surgery has proved to be a major success not only in terms of weight loss but also in the resolution of obesity related metabolic co-morbidities such as diabetes. So much so that these procedures are now advocated in diabetic patients with a BMI as low as 30kg/m² if hyperglycemia is inadequately controlled despite optimal medical therapy^{4, 5}. Never the less the high upfront costs of surgery and the requirement for specialist staff to deliver it, makes it an unlikely overall solution⁶.

Moving forward much more remains to be done to reduce this growing epidemic. Policy makers will need to formulate further interventions in both prevention and treatments. Novel ideas could include collaboration between food retailers and the NHS or health charities and early intervention at schools through an increased focus on dietary and physical education.

1. Finucane MM, Stevens GA, Cowan MJ, Danaei G, Lin JK, Paciorek CJ, et al. Lancet; 2011;377(9765):557–67. National, regional, and global trends in body-mass index since 1980: Systematic analysis of health examination surveys and epidemiological studies with 960 country-years and 9.1 million participants.

2. The World Health Organisation. Media centre Obesity and overweight. 2014;(January):1–5.

3. Malik VS1, Willett WC, Hu FB. Nat Rev Endocrinol. 2013 Jan;9(1):13-27. Global obesity: trends, risk factors and policy implications.

4. Rubino F, Nathan DM, Eckel RH, Schauer PR, Alberti KG, Zimmet PZ, Del Prato S, Ji L, Sadikot SM, Herman WH, Amiel SA, Kaplan LM, Taroncher-Oldenburg G, Cummings DE; Delegates of the 2nd Diabetes Surgery Summit. Obes Surg. 2017 Jan;27(1):2-21. doi: 10.1007/s11695-016-2457-9. Metabolic Surgery in the Treatment Algorithm for Type 2 Diabetes: a Joint Statement by International Diabetes Organizations.

5. Cefalu WT, Rubino F, Cummings DE. Diabetes Care. 2016 Jun;39(6):857-60. Metabolic Surgery for Type 2 Diabetes: Changing the Landscape of Diabetes Care.

6. Rubino F. Nature. 2016 May 26;533(7604):459-61. Medical research: Time to think differently about diabetes.