There are many misconceptions about boosting metabolism and weight loss, with most tactics falling into categories of harmful, illegal, or unfounded. Metabolism is largely influenced by the type of cells in the body, with muscle cells being more metabolically demanding than fat cells. While some lifestyle changes such as changing body composition and eating more protein and fiber can have a slight effect on metabolism, these effects are generally minimal. Additionally, our basal metabolic rate doesn’t begin to wane until around retirement age, not in our 30s or 40s as commonly believed. 

Key Points: 

1. There are no reliable or safe methods to significantly boost metabolism, despite common claims about diet routines and supplements.
2. Basal metabolism, the energy expenditure at rest, forms a large part of our daily energy use, and it’s influenced by the types and amounts of cells in the body. More muscle mass means more metabolically active cells, resulting in a slightly higher resting metabolism.
3. The relationship between metabolism and weight is complex. Two people with the same body weight but different body compositions can have different weight outcomes with the same caloric intake.
4. Introducing regular exercise and dietary changes like higher protein and fiber intake can slightly influence metabolism, but these effects are not substantial. Exercise, in particular, has limited impact on weight loss due to compensatory adjustments in the body.
5. The decline in basal metabolic rate doesn’t start until around the age of 60, contrary to common belief that it slows down during our 30s or 40s. Metabolic changes before this age may relate more to the reduction of muscle mass.

Continue reading at https://www.scientificamerican.com/article/can-you-change-your-metabolism/