The total number of adipocytes (fat cells) in your body can increase through late adolescence. After that age, you don't add more fat cells, but your adipocytes can expand or shrink in size.
Your body will store fat when your calorie intake is higher than your body's energy needs, resulting in weight gain. Remember, it's not just dietary fat that we hold on to; extra calories from any source, including carbs and protein, will get converted and stored as body fat.
The amount of energy each person requires daily varies, mainly based on body size and activity level. Our daily energy expenditure (calorie burn) has four components:
- Basal Metabolic Rate (BMR)/Resting Metabolic Rate (RMR): the energy needed to sustain basic life processes like brain and nerve function, circulation, renal function, etc.
- Physical Activity: the energy needed by the skeletal muscles for movement
- Thermic Effect of Food: diet-induced energy expenditure (cost of digestion)
- Thermoregulation: adjustments in metabolism to maintain core body temperature.
Obesity rates for the US population are over 40%, higher than they've ever been before. Modern conveniences make it easy to avoid physical activity and overconsume packaged, processed foods.
Unfortunately, it takes time and effort to exercise and prepare healthy meals . . . so it's tempting to look for a shortcut with fat-burning supplements. Just remember, the best thermogenic fat burner in the world won't work without a calorie deficit and building lean body mass through exercise.
Can Supplements Burn Fat?
Your body composition measures the percentage of fat in your body versus fat-free mass. So weight loss and fat loss, although related, aren't exactly the same thing. You may commit to a weight loss plan and see the number on the scale drop, but your body composition doesn't improve. This may indicate that you lost lean mass or water weight instead of burning fat stores.
Body mass can be classified into two categories:
Lean body mass (LBM) is also known as fat-free mass (FFM) or lean soft tissue (LST). LBM is the sum of total body protein, carbohydrates, nonfat lipids, soft tissue minerals, and body water, making up skeletal and nonskeletal muscle, organs, connective tissue, and bones.
Fat mass includes all your fatty tissue, connective tissue formed by adipocytes, collagenous and elastic fibers, capillaries, and fibroblasts.
When we talk about "burning fat," we're actually discussing how to increase fat metabolism: breaking down stored fat and using it for energy. Lipolysis is the term for this metabolic process, which utilizes fat for energy through beta-oxidation and ketone synthesis.
Most supplements claim to affect fat burning by mechanisms associated with:
- Suppressing appetite and food cravings
- Impairing fat absorption
- Increasing fat oxidation during exercise
- Stimulating hormones and enzymes involved in lipolysis
- Increasing metabolism/energy expenditure
Scientific research has mixed reviews on the efficacy of supplement fat burners. However, building lean muscle mass can help to increase your metabolism and burn more calories at rest.
Fat-burner supplements may aid fat loss by:
- Improving energy levels: giving you an energy boost to expend more energy (calories) throughout the day.
- Improving workout output allows you to burn more calories while exercising and build greater muscle mass.
- Improving lean muscle mass: which can boost metabolism over time.
- Improving fat digestion and lipolysis so that fat can be broken down, transported, and utilized for energy.
Before diving into the fat burner supplements, it's critical to cover a few precautions.