Epidemiological evidence has revealed the adversarial effects of ultra-processed food (UPF), particularly within the manifestation of obesity. Nevertheless, little or no evidence is obtainable that establishes causality. Recently, scientists reviewed the proposed mechanism related to UPF consumption and enhanced risk of obesity. This study is obtainable within the journal Advances in Nutrition.
Review: Ultra-Processed Foods and Obesity Risk: A Critical Review of Reported Mechanisms. Image Credit: beats1 / Shutterstock
Obesity and Dietary Recommendations
Obesity affects health negatively and likewise increases the burden on the healthcare system. Subsequently, it is crucial to develop primary and secondary prevention strategies, including encouraging a healthy weight loss plan.
Recent studies have shown that food processing is directly linked to the obesity epidemic. To amend this, for dietary guidance, a classification system (NOVA) was developed. NOVA comprises 4 food groups, including UPF, which is thought to be essentially the most problematic food type. It’s because UPF has a high concentration of added salt, sugar, and fats. These foods are designed to be hyper-palatable, convenient, profitable, and have a stable shelf life.
Based on the NOVA classification system, moderate UPF consumption has been approved by the World Health Organization. The “Great Debates” series within the American Journal of Clinical Nutrition highlighted the talk that increased consumption of UPF enhances BMI within the population. Although multiple meta-analyses and systematic reviews have shown that UPF consumption results in obesity, these findings can’t be used to formulate a strong dietary advice.
Dietary recommendations are developed based on epidemiological, mechanistic, and controlled clinical trial data, that are currently lacking. This approach helps describe the scope of the issue, discover the vulnerable group, establish causality, and characterize the underlying mechanism liable for the issue.
UPF vs. NUPF
So far, no studies have documented the mechanistic link between UPF and increased body weight. Many European countries obtain between 50% and 91% of nutrients from highly processed food. Interestingly, a recent American cohort study reported that UPF significantly contributes to vitamin E, folate, calcium, thiamine, and niacin. Nevertheless, it isn’t clear whether this finding was based on minimally processed food.
Typically, non-UPF (NUPF) are dearer and require a high preparation time. These foods are restricted to specific geographic areas and are subject to availability. NUPFs even have a shorter shelf life, increasing the danger of food spoilage and food poisoning. Food processing entails food safety by increasing food shelf life via the addition of preservatives.
Underlying Mechanisms Linked to UPF and Obesity
The underlying mechanisms related to the consumption of UPF and obesity have been categorized into three groups, i.e., food alternative, food composition, and digestive processes. Food alternative is related to shelf-life, cost, packaging, hyper-palatability, and stimulation. Food composition deals with dietary content, texture, added fat, sugar and salt, calories, energy density, additives, and sweeteners. Digestive processes are linked with the gut microbiome, gastrointestinal transit time, gastric emptying time, and oral processing/eating rate.
The NOVA system provides guidance for optimal food decisions that profit health. It only points out foods that should be avoided as a substitute of providing guidance on portions or frequencies that aids in obesity. The nutrient contents of food should not discussed by NOVA. Adherence to NOVA recommendations is debatable, particularly linked to UPFs.
Initially, the high sugar, salt, and fat content in UPF were considered the foremost culprits promoting weight gain. Later, the economic food processing system was considered the causal agent of adversarial issues. It was again proposed that food formulation, as a substitute of processing, promotes adversarial health effects. More recently, scientists have been concerned concerning the unintentional introduction of harmful elements, equivalent to heavy metals, into the food chain and sustainability.
Interestingly, UPF intake was not at all times linked with weight gain, and hyper palatability or altered appetite didn’t at all times affect gut hormones or eating rates. Not much data was found on the effect of dietary fiber (high or low), food texture, gastric emptying, and intestinal transit time linked to UPF on the incidence of obesity. Because of insufficient data on the microbiome, food additives, food cost, appetite stimulation, and packaging, the advantages and risks related to UPF avoidance couldn’t be determined.
Selecting a properly balanced and varied weight loss plan is important and very helpful to health. Balance and variety are two fundamental principles of the guidance offered by the World Health Organization and the Food and Agriculture Organization for sustainable healthy diets.