Are you or your clients finding it hard to stop consuming the foods carefully designed to enhance all of the reward centre’s responses when consumed?
Ultra-processed foods (UPF) have received exponential levels of investment to ensure they are engineered to be as easy as possible to consume and re-consume. This technical processing reduces the capability of key fullness receptors and hormones such as leptin, insulin, cholecystokinin, peptide YY, glucagon-like-peptide-1, ghrelin and amylin to respond soon enough to prevent overconsumption[1]. This sensory favouring engineering has a consequence which is then reflected in a rising prevalence of all the major chronic diseases, rising health care costs and declining population health and productivity[2].
Ultimately this means that these foods can be very difficult to reduce the intake of. A positive outcome for the manufacturer’s balance sheet with worldwide processed food sales totalling about $2 trillion, but a personal and globally adverse outcome for everyone else from a health and biodiversity impact[3].
A recent analysis of two systematic reviews exploring the prevalence of ‘addictive behaviour’ towards ultra-processed food (UPF) including 281 studies from 36 different countries rated the overall pooled prevalence of food addiction using the Yale Food Addiction Scale (YFAS). The YFAS assesses all 11 symptom criteria for substance use disorder in Diagnostic and Statistical Manual of Mental Disorders (DSM-5)[4]. These include diminished control over intake, cravings, withdrawal, and continued use despite negative consequences, to be 14% in adults and 12% in children[5],[6].
This reported prevalence of addictive behaviour is similar to the levels of addiction seen for other legal substances in adults (e.g., 14% for alcohol and 18% for tobacco)[7]. UPF addiction based on the YFAS is also associated with core mechanisms of addiction, such as reward-related neural dysfunction, impulsivity, and emotion dysregulation, as well as poorer physical and mental health and lower quality of life. It is further increased in those people that are obese and have a binge eating disorder2.
What types of foods can be addictive?
It will come as no surprise that foods with high levels of refined carbohydrates or added fats, such as sweets and salty snacks are most strongly implicated in the behavioural indicators of addiction[8]. These engineered elements evoke similar levels of extracellular dopamine in the brain striatum to those seen with addictive substances such as nicotine and alcohol[9].
While natural or minimally processed foods typically contain either carbohydrates or fat, they rarely contain both, for example, 100 g of apple has 55 kcal from carbohydrates and 1.5 kcal from fat (roughly 36:1) and 100 g of salmon has 0 kcal from carbohydrates and 73 kcal from fat (roughly 0:1). By contrast, many UPF’s contain much higher levels of both carbohydrates and fats in more equal proportions. For example, 100 g of a chocolate bar contains 237 kcal from carbohydrates and 266 kcal from fat (1:1). The combination of refined carbohydrates and fats often found in UPFs seems to have a supra-additive effect on brain reward systems, above either macronutrient alone, which may increase the addictive potential of these foods[10].
Additives in UPFs may also make these foods more addictive. Many UPFs contain extra flavours that make them taste better and substances that improve their texture. These are similar to additives found in cigarettes, such as sugar and menthol, which are not just for taste but also to make customers keep coming back for more. Just like some smokers might prefer cigarettes without nicotine just for the flavour and experience, food additives might not be addictive by themselves but could strengthen the desire for the food because of the calories they come with and can also contribute to altered gut health.[11],[12]
Clinical implications
When people who are obese or have eating disorders are also addicted to UPFs, their health problems tend to be more serious. They can have more diet-related diseases, increased incidences of dysbiosis, more mental health issues, trouble thinking clearly, and they do not respond as well when treated[13]. Even though understanding UPF addiction could be important for healthcare, there isn’t much research on how to treat or prevent it. Most of the studies so far have been about whether UPF addiction is a real thing, and only now are experts starting to create guidelines for dealing with it.
Possible strategies
The focus for nutrition-orientated health care professionals will be on addressing UPF-related nutrient deficits, and whilst this may seem counterintuitive, the absence of micronutrients essential for the proportional endocrine responses to UPFs serve to exacerbate the challenges of behaviour change. Given the ample availability and accessibility of UPFs globally, achieving complete abstinence is likely unfeasible and unnecessary, when modifications to food selection and enhanced nutrient ingestion, along with other harm reduction and other moderation-based approaches may be enough to start the necessary health generational changes.
There’s a growing interest in how diet and specific micronutrients might influence behaviour related to the consumption of UPFs, potentially by affecting hormonal responses and brain function. No definitive micronutrient list exists that can guarantee a reduction in the consumption of UPFs, but some have been associated with improved hormonal balance and might help mitigate cravings or overeating[14]:
- Magnesium: This mineral is involved in over 300 enzymatic reactions in the body, including those related to the regulation of blood glucose and insulin sensitivity, which can affect hunger and cravings[15].
- Omega-3 Fatty Acids: Found in fish oil, flaxseeds, and walnuts, these fatty acids are crucial for brain health and have been shown to influence dopamine and serotonin levels, which play roles in appetite regulation and cravings[16].
- Fibre: While not a micronutrient, dietary fibre from whole foods can improve gut health and the release of satiety hormones like GLP-1. Fibre can help slow the absorption of sugar into the bloodstream, leading to more stable blood sugar levels and potentially reduced cravings[17].
- Vitamin D: Low levels of vitamin D have been linked to an increased risk of weight gain and metabolic syndrome. Adequate vitamin D levels may help improve leptin sensitivity and function, which helps regulate energy balance and body weight[18].
- B Vitamins: Particularly vitamin B6 and B12, are essential for energy metabolism and neurotransmitter function, which can influence eating behaviour and cravings[19].
- Zinc: Zinc plays a crucial role in appetite regulation and the proper function of leptin, the satiety hormone. Zinc deficiency can disrupt leptin signalling and may lead to increased hunger and potentially a higher intake of ultra-processed foods[20].
- Chromium: This trace mineral is known to enhance the action of insulin and is thought to influence hunger, satiety, and cravings, particularly for carbohydrates[21].
Summary
Food purchases are driven by taste, value, convenience, nutrition, and sustainability. As our lifestyles have changed, we have been able to spend less money on food and less time on shopping and cooking. Food processing and formulation therefore have both advantages and disadvantages, and current recommendations to remove all UPFs from the diet despite clear long-term nutritional, biodiversity and societal benefits are likely regressive and unrealistic.
Disproportionately taxing foods by their degree of processing is likely to disproportionately affect the most vulnerable and food-insecure consumers without some compensatory cost benefit to consume non-processed or minimally processed food being similarly applied.
While some sectors of the population will reduce the proportion of processed foods in their diet subsequent to understanding their need to do so, for most consumers it will be difficult or impossible to do so and still meet their daily gross nutrient requirements. It may be necessary to reformulate with nutrient fortification certain elements of the current food supply or additionally supplement, to ensure that foods remain appealing and convenient but also have the appropriate micronutrient density for different populations[22]
In addition, utilising food supplements designed to facilitate increased levels of control over changes in metabolic functionality and insulin resistance, together with behavioural interventions represents a way to enhance the transfer from UPFs to foods and lifestyle that align with long term health, such as those found in the Mediterranean lifestyle and diet[23].
References
[1] Anthony Y. Yeung; Prasanna Tadi. Physiology, Obesity Neurohormonal Appetite And Satiety Control
[2] Rebalancing global power asymmetries to substantially improve human and planetary health (infographic – Lancet)
[3] Leite FHM, Khandpur N, Andrade GC, et al Ultra-processed foods should be central to global food systems dialogue and action on biodiversity BMJ Global Health 2022;7:e0082
[4] Ashley N. Gearhardt and Erica M. Schulte. Is Food Addictive? A Review of the Science. Annual Review of Nutrition 2021 41:1, 387-410
[5] Praxedes DRS, Silva-Júnior AE, Macena ML, et al. Prevalence of food addiction determined by the Yale Food Addiction Scale and associated factors: a systematic review with meta-analysis. Eur Eat Disord Rev2022;30:85-95
[6] Yekaninejad MS, Badrooj N, Vosoughi F, Lin CY, Potenza MN, Pakpour AH. Prevalence of food addiction in children and adolescents: A systematic review and meta-analysis. Obes Rev. 2021 Jun;22(6):e13183.
[7] Gearhardt A N, Bueno N B, DiFeliceantonio A G, Roberto C A, Jiménez-Murcia S, Fernandez-Aranda F et al. Social, clinical, and policy implications of ultra-processed food addiction BMJ 2023; 383 :e075354
[8] Schulte EM, Avena NM, Gearhardt AN. Which foods may be addictive? The roles of processing, fat content, and glycemic load. PLoS One. 2015 Feb 18;10(2):e0117959.
[9] Di Chiara G, Imperato A. Drugs abused by humans preferentially increase synaptic dopamine concentrations in the mesolimbic system of freely moving rats. Proc Natl Acad Sci U S A1988;85:5274-8.
[10] DiFeliceantonio AG, Coppin G, Rigoux L, et al. Supra-additive effects of combining fat and carbohydrate on food reward. Cell Metab 2018;28:33-44.e3
[11] Torii K. Brain activation by the umami taste substance monosodium L-glutamate via gustatory and visceral signaling pathways, and its physiological significance due to homeostasis after a meal. J Oral Biosci2012;54:144-50
[12] Raoul P, Cintoni M, Palombaro M, Basso L, Rinninella E, Gasbarrini A, Mele MC. Food Additives, a Key Environmental Factor in the Development of IBD through Gut Dysbiosis. Microorganisms. 2022 Jan 13;10(1):167.
[13] Munguía L, Gaspar-Pérez A, Jiménez-Murcia S, et al. Food addiction in eating disorders: a cluster analysis approach and treatment outcome. Nutrients2022;14:1084.
[14] Basiri R, Seidu B, Cheskin LJ. Key Nutrients for Optimal Blood Glucose Control and Mental Health in Individuals with Diabetes: A Review of the Evidence. Nutrients. 2023 Sep 10;15(18):3929.
[15] Rodríguez-Morán M, Guerrero-Romero F. Oral magnesium supplementation improves insulin sensitivity and metabolic control in type 2 diabetic subjects: a randomized double-blind controlled trial. Diabetes Care. 2003 Apr;26(4):1147-52.
[16] Im DS. FFA4 (GPR120) as a fatty acid sensor involved in appetite control, insulin sensitivity and inflammation regulation. Mol Aspects Med. 2018 Dec;64:92-108.
[17] Kim YA, Keogh JB, Clifton PM. Probiotics, prebiotics, synbiotics and insulin sensitivity. Nutr Res Rev. 2018 Jun;31(1):35-51.
[18] Madhu SV, Aslam M, Mishra BK, Gupta A, Jhamb R. Association of 25 (OH) Vitamin D and Leptin in Individuals with Insulin Resistance. Indian J Endocrinol Metab. 2022 Sep-Oct;26(5):435-438.
[19] Hanna M, Jaqua E, Nguyen V, Clay J. B Vitamins: Functions and Uses in Medicine. Perm J. 2022 Jun 29;26(2):89-97.
[20] Baltaci AK, Mogulkoc R. Leptin and zinc relation: In regulation of food intake and immunity. Indian J Endocrinol Metab. 2012 Dec;16(Suppl 3):S611-6.
[21] Vincent JB. Effects of chromium supplementation on body composition, human and animal health, and insulin and glucose metabolism. Curr Opin Clin Nutr Metab Care. 2019 Nov;22(6):483-489
[22] Harlan TS, Gow RV, Kornstädt A, Alderson PW, Lustig RH. The Metabolic Matrix: Re-engineering ultraprocessed foods to feed the gut, protect the liver, and support the brain. Front Nutr. 2023 Mar 30;10:1098453.
[23] Maroto-Rodriguez J, Delgado-Velandia M, Ortolá R, Perez-Cornago A, Kales SN, Rodríguez-Artalejo F, Sotos-Prieto M. Association of a Mediterranean Lifestyle With All-Cause and Cause-Specific Mortality: A Prospective Study from the UK Biobank. Mayo Clin Proc. 2023 Aug 8:S0025-6196(23)00305-1.