Obesity is defined as abnormal fat accretion which may cause adverse harm to your health. Body Mass Index(BMI) is a fundamental guide of weight-for-height which is commonly used to identify overweight and obesity in adults. The BMI of a person can be estimated as the weight in kilograms divided by the square of their height in meters (kg / m2).
Study Reveals, Ways To Reduce Resting Metabolic Rate After Weight Loss
Globally, obesity has increased thrice than the past decades with 1.9 billion and 650 million overweight adults, consecutively. Weight loss is enabled through the induction of a negative energy balance that is promoted to treat obesity, even with modest weight loss, which leads to improved health.
The latest study published in the International Journal of Obesity determines the assistance of energy-wasting tissue loss and metabolic adaptations to the reduction of metabolic rate (RMR) during rest after weight loss.
The major aim of the study was to estimate the contribution and connection of two elements that helped in the decline of RMR during long-term weight loss in healthy normal-weight and overweight individuals.
To achieve this goal, the researchers have retrospectively examined the data from the Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy (CALERIE), a large-scale, randomized controlled trial.
The earlier reported variability in changes in body composition and RMR allowed the study of individual variability in the contribution of tissue loss and metabolic adaptations to the reduction of RMR after weight loss.
Calorie restriction is the most familiar process of weight loss, and although originally effective, long-term calorie limitation results in impaired weight loss. This weakening of weight loss is due to a decline in total daily energy expenditure (TDEE), which counteracts the lack of initial energy.
These reductions in TDEE result in a lower return to energy balance, which raises the possibility of energy overload after cessation of weight loss efforts, and encourages people to retrieve weight in the future.
Although reductions in weight loss have been notified for most components of TDEE, deductions in resting metabolic rate (RMR) are most consistent. RMR is defined as the energy spent at rest for physiological performance and accounts for ~ 60-70% of TDEE in the normal population, making it the largest contributor to TDEE. Thus, its protection during weight loss is targeted as a potential strategy to prevent balanced reductions in TDEE and following weight recovery.
Since fat-free mass (FFM) is traditionally considered the main determinant of RMR, it is believed that the protection of RMR is enhanced when FFM is maintained during weight loss.
In addition, FFM failures can register for up to 50% of total weight loss, and therefore can partially explain the flexibility followed in RMR after weight loss. Nevertheless, FFM is a heterogeneous tissue, and the rate of RMR reduction due to FFM loss is greatly forced by the size and metabolic conditioning of specific tissues lost.
Although both of these different events ie, loss of energy-consuming tissues and decreased metabolic activity of the remaining tissues, contribute to a decrease in RMR, it is undefined whether each participant occurred independently or was affected by the magnitude of different tissue losses that affect the proportion of RMR deduction and metabolic transformations.
The analysis shows that after losing weight, in healthy normal weight and overweight people, RMR inevitably decreases, and this decrease occurs as a result of loss of energy-consuming tissues and metabolic adaptations.
Assumptions, loss of energy-consuming tissues (mainly skeletal muscle and adipose tissue) contributed to a decrease in RMR, although on average only ~ 60% (60 ± 3 kcal/day) leaving the remaining 40% RMR decrease explicable to metabolic adaptations (40 ± 11 kcal/day). More significantly, the subsidy of tissue losses and metabolic adaptations to the overall RMR decline was highly unstable among individuals.
The adipose tissue loss was associated with decreased RMR and metabolic adaptations, so metabolic adaptations were highest in people who lost the most adipose tissue.
Given the different effects of these components on RMR reduction after weight loss, future studies should scrutinize whether tissue or their metabolic activity protection has differential consequences on RMR reduction and weight maintenance and whether more unique strategies targeting the distinct cause of RMR deduction can maximize weight loss and prevent re-gaining weight.