In a recent study published in Signal transduction and targeted therapy journal, researchers assessed the impact of dietary regulation on human health and disease.
Adequate proportions of nutritional treatment play an essential role in extending lifespan as well as delaying the aging process in several species, including Drosophila, yeast, primates, rodents, and humans. Therefore, there is enormous potential in the development of precision nutritional therapeutics against age-related biological mechanisms and several diseases.
Dietary intervention in human health and disease
In the present study, researchers summarized the various forms of dietary regulations prescribed to improve human life span and the treatment of various diseases in clinical or preclinical settings.
Because diet-mediated signaling is found throughout the human body, the effects of dietary interventions are assumed to be random across all organs and tissues. Nutrients affect human tissues to varying degrees and in several ways that have been shown to treat disease while enhancing therapeutic effect. The team developed the mechanisms that help dietary interventions support precision nutrition therapy.
Various studies have shown the impact of overeating on accelerating disease progression, including type 2 diabetes and obesity. Several diseases such as cardiovascular disease (CVD), cancer, diabetes and non-alcoholic fatty liver disease (NAFLD) are positively associated with obesity. A high-fat diet, together with excessive consumption of branched-chain amino acids (BCAAs), methionine and tryptophan and its metabolites, have led to obesity-related diseases and weight gain. Calorie restriction (CR) has been observed to reduce gamma-glutamyl transferase (GGT) and alkaline phosphatase (ALP) concentrations in healthy adults and improve liver function.
Moreover, intermittent fasting (PF) reduces high-risk factors associated with aging-related diseases and cancer. Compared with controls, time-restricted feeding (TRF) significantly reduced oxidative stress and insulin resistance while improving cardiometabolic health in patients with metabolic syndrome. Moreover, every-other-day routine fasting (EODF) remarkably attenuates NAFLD, obesity, and insulin resistance.
The team noted that the effects of TRF on reducing body fat and body weight were no greater than those seen with daily CR among obese individuals. Therefore, alternation of dietary components is considered a possible mechanism for the treatment of metabolic syndrome. BCAA restriction has also been found to improve health in obese and non-obese individuals. Overall, the team observed a clear link between metabolic disorders and nutritional interventions that could be used as an adjuvant approach to treat metabolic syndromes.
Diets high in fat or salt and diets high in BCAA concentrations are high risk factors for cardiovascular disease (CVD). Dietary intake of BCAAs has been found to significantly facilitate platelet activation, thereby increasing the risks associated with CVD and arterial thrombosis. A study shows the impact of CR in reducing the adverse effects of CVD while improving cardiac function along with reducing cholesterol concentrations. Triglycerides and low-density lipoprotein (LDL). A potential mechanism used by CR is the reduction of free leptin by CR in plasma, which reverses the process of myocardial hypertrophy and reduces lipid accumulation. The team also noted that CR reduced fibrosis, oxidative stress, myocyte hypertrophy and cardiac inflammation in mice.
A five-day fasting-mimicking diet (FMD) has also been shown to improve the loss of subcutaneous and visceral fat and prevent obesity-related damage to cardiac function and vascularity. Furthermore, consumption of a high-fiber diet increased the richness of microbial communities such as Bacteroides acidifaciens generated from short-chain fatty acids (SCFA).
Digestive disorders such as Crohn’s disease and colitis are managed using nutritional therapies. For example, long-term consumption of red meat is associated with an increased risk of digestive disorders. N-glycolylneuraminic acid (Neu5Gc), found in red meat, is a potential factor in promoting inflammatory disorders and carcinomas. In active human Crohn’s disease, ω-3 and ω-6 polyunsaturated fatty acids (PUFAs) induce the expression of chemokines in epithelial cells, leading to toll-like receptor 2 (TLR2) activation. Dietary restrictions have also been found to improve intestinal barrier function and provide intestinal homeostasis and alter the gut microbiome.
Dietary interventions also affect renal function, as protein intake has been found to exacerbate risk factors associated with chronic kidney disease (CKD) in mouse models. High protein intake increases concentrations of uremic toxins, including indole, microbial indoxyl sulfate, and hydrogen sulfide. Excessive dietary salt intake also potentially worsens symptoms associated with kidney disease. Recent studies have reported that dietary protein restriction reduces renal ammonia excretion through changes in ammonia metabolism.
Overall, the study results suggest that nutritional intervention can be an effective treatment method to maintain human health and counteract morbidity.