How to speed up your metabolism? A dietitian explains

Metabolic rate is not a fixed, unchanging value encoded in our genes that absolutely determines our weight. It is a dynamic and extremely complex system. The key to modifying body weight is not having a fast metabolism, but creating a behavioral and caloric environment that forces the metabolic system to adapt as desired.

• To improve your metabolism effectively and healthily, you should build muscle mass (strength training), maintain high levels of spontaneous activity (e.g., take the stairs instead of the elevator), eat an adequate amount of protein, and prioritize sleep, hydration, and stress reduction;
• Metabolism isn’t just about burning calories – it encompasses all the chemical and energy processes occurring within cells that allow the body to function;
• Not every person who is overweight or obese has a slow metabolism;
• Metabolism can adapt to attempts to lose or gain weight and adjust its rate. Understanding this mechanism can help you achieve your weight goals;
• It is impossible to permanently “boost your metabolism” with a single product, supplement, or detox. Real support comes from strength training, daily activity, adequate protein intake, hydration, sleep, stress reduction, and avoiding extremely low-calorie diets.

Metabolism (or metabolic processes) refers to all the chemical reactions and associated energy transformations that constantly occur within living cells. It is the mechanism by which the body absorbs nutrients from the environment, processes them, extracts energy from them, builds its own structures, and excretes waste products.

Metabolism is based on a constant balance between two opposing but closely related processes: anabolism and catabolism.

Anabolism, or synthesis processes, can be understood as “building” processes in our body that require an external energy supply. An example is the formation of new cells and tissues during wound healing.

Catabolism, or breakdown processes, can be understood as processes of “destruction or release.” These are reactions involving the breakdown of complex organic compounds into simpler substances. Energy is released during these processes. Examples include food digestion or the burning of fat tissue to obtain energy during a caloric deficit.

When we say someone has a fast metabolism, we mean that their body burns a lot of energy throughout the day. Such a person may have a higher caloric requirement, including that related to their basal metabolic rate, and may have difficulty gaining weight.

A slow metabolism is the opposite of this. Their body uses less energy, has a lower caloric requirement, and it is easier for them to gain weight.

It is worth remembering, however, that metabolism does not affect only body weight and metabolism. It is the foundation of the internal balance of the entire body and its proper functioning: including the efficiency of the immune system, the brain, and the ability to regenerate during sleep.

The belief that metabolism is solely responsible for whether we are thin or overweight is false. Boosting your metabolism can help you maintain a healthy weight, but the most important factors for this goal remain a well-balanced and nutritious diet and optimal levels of physical activity. Properly regulating your metabolism can not only help you change the numbers on the scale but also support maintaining a good mood, immunity, fertility, and even longevity.

It is not true that thin people always have a fast metabolism, and those who are overweight or obese have a slow one. This is one of the most common and harmful oversimplifications in nutrition.

Overweight and obese people have a higher basal metabolic rate (BMR) than thin people. BMR depends directly on the total mass of metabolically active tissues. A person with a higher body weight (even if a significant percentage of it is adipose tissue) has:

• a larger volume of internal organs (liver, kidneys, heart), which generate the greatest energy expenditure at rest;
• greater skeletal muscle mass, necessary to move a heavier body weight;
• adipose tissue itself, which, although not very active (approx. 4.5 kcal/kg/day compared to muscle – approx. 13 kcal/kg/day), also generates a noticeable metabolic cost when present in large volumes.

For this reason, a large body (an obese person) consumes more energy at rest than a small body (a slim person).

The difference in the ease of maintaining a slim figure does not stem from an “innate fast resting metabolism,” but may be linked, among other things, to two other mechanisms:

1. A decrease in daily spontaneous activity unrelated to exercise: people genetically predisposed to being slim respond to a caloric surplus with a subconscious, sudden increase in spontaneous movement (e.g., fidgeting, pacing while on the phone). In people prone to obesity, this mechanism does not occur, and the excess is directly stored;
2. Neurohormonal signaling: in some people, the body is less effective at recognizing hunger and satiety signals. Hormones (leptin, ghrelin, and insulin) may function less effectively, which can lead to chronically exceeding caloric needs.

Read: Why am I not losing weight if I’m eating less?

It’s also worth remembering the adaptive function of metabolism. When we eat fewer calories than we need, we start to lose weight, but after a while, our metabolism may “notice” that there is less energy and begin to conserve it. Under conditions of a calorie deficit, so-called adaptive thermogenesis (metabolic adaptation) occurs – the body significantly reduces its energy expenditure and, for example, decreases heat production or reduces spontaneous activity (we move less and gesture less).

This can be a potential source of a plateau in the weight loss process. We may maintain a calorie deficit that previously caused us to lose body weight, but the weight suddenly starts to drop more slowly or even stops altogether. In this way, the body tries to protect its energy reserves.

Therefore, whether we want to lose or gain weight, it is important to properly manage the changes in metabolic rate that occur during the process of weight loss or weight gain.

Metabolic rate is, in practice, the body’s ability to respond flexibly to energy intake (metabolic flexibility). We can assess it through:

• indirect calorimetry (the gold standard): a test performed in a clinical setting. It involves measuring oxygen consumption (VO2) and carbon dioxide production (VCO2) at rest. It allows us to determine exactly how many calories the body burns during basal metabolism and whether it is primarily “burning” fats or carbohydrates at any given moment;
• body composition analysis (BIA – Bioimpedance): professional devices allow for the determination of lean body mass. As we already know, it is this mass (especially muscle) that is the main determinant of basal metabolic rate;
• glucose monitoring: continuous glucose monitoring allows us to assess how well your metabolism handles energy utilization. Frequent spikes and prolonged high glucose levels after a meal indicate poor metabolic flexibility and insulin resistance;
• keeping a food diary and measuring body weight: if you consume X calories and your body weight remains stable, you know your actual metabolic rate (BMR – basal metabolic rate). Online calculators provide only estimates – we can determine your actual metabolism by checking your energy balance in practice.

Metabolism doesn’t work like a switch that can be easily “turned up” or “turned down.” It is the sum of processes during which the body uses energy. You cannot “speed up your metabolism” permanently with a single product, drink, or supplement. However, you can influence how much energy your body uses throughout the day. How can you achieve this? Using evidence-based methods, which you’ll read about below.

Metabolic Restart is a medical residential program during which our patients restore their metabolic balance. We rely exclusively on proven, science-backed methods. We do not promise a magical “weight loss package.” We teach you how to effectively change your lifestyle.

Our program is a scientific process of restoring metabolic balance, based on the latest medical advances, clinical practice standards, and research findings. We bring together the care of an interdisciplinary team of specialists to offer patients personalized and comprehensive therapy in one place, tailored specifically to their situation.