Challenges and opportunities for better nutrition science—an essay by Tim Spector and Christopher GardnerBMJ 2020; 369 doi: https://doi.org/10.1136/bmj.m2470 (Published 26 June 2020) Cite this as: BMJ 2020;369:m2470
All rapid responses
We welcome Spector and Gardner’s1 timely essay on the opportunities for better nutritional science. As jobbing NHS psychiatrists, we know too well that people with severe mental illness such as psychosis disproportionately suffer from obesity, metabolic syndrome and type 2 diabetes, often secondary to the adverse effects of antipsychotic medication2. Some would argue that patients detained under the Mental Health Act may be at further risk of developing metabolic problems due to meals lacking nutrition provided in hospital settings. Despite the introduction of NHS England physical health CQUINs in mental health settings, weight gain is often monitored poorly and any interventions offered are ineffective. The recommended interventions in the NICE guidelines on obesity3 include calorie restriction and low-fat diets which we argue are outdated methods of weight management. Weight gain is unfortunately seen as an inevitable consequence of taking psychotropic medication.
Furthermore it is notable that severe mental disorders such as psychosis disproportionately affect lower socioeconomic groups, as does obesity. Structural inequalities exist such that makes it very difficult for people on a limited income to buy fresh produce and to avoid buying ultra-processed food. Supermarkets are structured in a way that maximises sales of its least healthy foods and ultra-processed food products are often marketed as healthy with attractive branding. The harsh reality is that the food industry controls much of what we eat. It follows then that the term “lifestyle medicine” may be a misleading term as some people’s choices are very limited.
The lack of consensus of what constitutes a healthy diet is deeply concerning. Nutritional experts often disagree with one other and there is a plethora of contradictory diets. As a result mental health professionals do not feel confident about giving nutritional advice to their patients and the public are unsurprisingly confused about what a healthy diet is.
What is emerging and gaining traction is a growing body of evidence of weight management on low carbohydrate diets. We are encouraged by the recent work of Unwin and Unwin4 in reversing type 2 diabetes through the low carbohydrate diet in their cohort of community patients in primary care. We also welcome the recent reassessment of recommendations around foods rich in saturated fat, that the available evidence does not recommend limiting these foods5.
We can see that the tide is turning but it remains a travesty that better nutritional research does not exist, particularly for patients with severe mental illness. We owe it to our patients to do better.
Reem Abed and Gurpreet Kaler
Spector TD, Gardner CJ. Challenges and opportunities for better nutrition science BMJ 2020; 369:m2470. doi: https://doi.org/10.1136/bmj.m2470
De Hert M, Correll C, Bobes J et al. Physical illness in patients with severe mental disorders. I. Prevalence, impact of medications and disparities in health care World Psychiatry 2011; 10(1): 52–77. doi: https://dx.doi.org/10.1002%2Fj.2051-5545.2011.tb00014.x
NICE 2014. Obesity: Identification, Assessment and Management [Online]. Available at: https://www.nice.org.uk/guidance/cg189/resources/obesity-identification-... [Accessed: 1 July 2020].
Unwin D, Unwin J. Low carbohydrate diet to achieve weight loss and improve HbA1c in type 2 diabetes and pre-diabetes: experience from one general practice Practical Diabetes 2014; 31(2): 76-79. doi: https://doi.org/10.1002/pdi.1835
Astrup A, Magkos F, Bier DM et al. Saturated fats and health: a reassessment and proposal for food-based recommendations: JACC state-of-the-art review JACC 2020; doi: https://doi.org/10.1016/j.jacc.2020.05.077
Authors’ declaration of interest: none
Competing interests: No competing interests