Metabolism is the process of breaking down proteins, fats, and carbohydrates. The body ends up with the energy it needs to live and be healthy. When we are young, our bodies run like clockwork, have reserves, and we don’t even pay attention to how efficiently they process energy. This aspect of our health becomes interesting to us as we age, especially when weight problems appear. Let’s find out how the body’s energy balance changes with age in men and women.
How metabolic rate changes with age
A recent study examined the metabolism of 6,500 people around the world, from newborn babies to ninety-year-olds. The work involved more than 80 scientists who tried to combine studies from the last 40 years. The results of the work are really impressive.
Experts have always assumed that the body’s energy system peaks in adolescence and slows down significantly as we approach middle age, after the age of 30 or 40. However, a study refutes this fact. Scientists have found that caloric processing speeds up much earlier and slows down much later. As a result of many years of observation, they found that biochemical processes remain maximally stable from the age of 20 to 60 and only start to decline in the seventh decade.
There are four stages in the development of the body’s metabolic rate:
- Metabolism peaks in the first year of a person’s life. At this age, a child burns calories 50% faster than an adult.
- From age one to age 20, the rate decreases by about 3% per year.
- From age 20 to 60, the metabolic rate reaches a plateau, remaining unchanged.
- After age 60, it gradually slows down – by about 0.7% per year.
Who has a faster metabolism – women or men
For a long time, it was assumed that men have a much faster metabolic rate than women. But this theory has not been confirmed. On average, men burn more calories per day than women, but only because they tend to be larger, have slightly less fat, and more muscle. If you take these differences into account, the rate of energy expenditure is the same. A man and a woman with the same body weight and the same percentage of body fat will have the same efficiency in processing calories.
How to speed up your metabolism
- Nutrition
Nutrition is the key to a healthy metabolism, and the main nutrient that affects metabolism is protein. It is responsible for muscle, organ and hormonal health. Protein is 30% more difficult to digest than carbohydrates and fats, leading to increased energy expenditure and weight loss on a high-protein diet. As we age, the ability to digest protein decreases and a person begins to prefer carbohydrates. This leads to a decrease in muscle mass and metabolic disorders.
- Exercise
Mobility is important. Aerobic and anaerobic exercise keeps energy production at optimal levels, strengthens the cardiovascular system and skin health. Lack of physical activity worsens taste preferences, and as people age, they often begin to avoid movement, which only exacerbates metabolic problems. “Sedentary lifestyle” has a negative impact on health, creating conditions for stagnant processes in the body.
- Cold and heat
Excessive desire for heat disrupts metabolism, because humans need movement, food extraction and hormone production. The processes of hardening and physical activity promote the production of mitochondria, which are a source of energy. Lack of exercise and improper regimen leads to a decrease in energy.
- Green tea, coffee, spices
Green tea and coffee may stimulate the nervous system and speed up metabolism, but they also remove important micronutrients. Herbal collections give the same beneficial effects without the side effects. Hot spices also activate metabolic rate, but their effect on fat burning is limited.
- Sleep
Sleep deprivation upsets the balance of hormones: ghrelin (hunger hormone) rises and leptin (satiety hormone) falls, leading to overeating. Lack of sleep also raises cortisol levels, which disrupts metabolism and can cause rash behavior.
Hormonal changes and their impact
Hormones play a major role in regulating metabolism. For instance, growth hormones, thyroid hormones, and insulin are all integral to metabolic function. As we age, the production of these hormones gradually decreases, which can directly affect how efficiently the body processes food and burns energy. For example, a decline in thyroid function (hypothyroidism) is common with age, leading to a slower metabolism and weight gain.
Additionally, changes in the levels of estrogen and testosterone can influence how fat is distributed in the body. In women, the decline in estrogen levels during menopause can lead to an increase in abdominal fat, while in men, a drop in testosterone can lead to a decrease in muscle mass, both of which contribute to slower metabolic rates.
The influence of hydration on metabolism
Water plays a crucial role in maintaining a healthy metabolism. Every metabolic process in the body requires water, from digesting food to transporting nutrients and eliminating waste. Even mild dehydration can slow metabolism, leading to fatigue, headaches, and reduced energy levels. Studies show that drinking enough water can temporarily increase metabolic rate by up to 30% as the body expends energy to heat the water to body temperature.
Additionally, proper hydration supports kidney function, preventing toxins from accumulating in the body. When the kidneys do not receive enough water, the liver takes over some of their functions, reducing its efficiency in metabolizing fat. This can slow down fat-burning processes and contribute to weight gain. To support metabolism, it is recommended to drink at least 2–2.5 liters of water per day, adjusting intake based on physical activity levels and climate conditions.
The role of gut health
The gut microbiome, which consists of trillions of bacteria living in the digestive tract, plays a key role in metabolism. These bacteria help break down food, synthesize vitamins, and regulate immune function. An imbalance in gut bacteria (dysbiosis) can slow down digestion, impair nutrient absorption, and contribute to metabolic disorders, including obesity and diabetes.
Studies suggest that individuals with a diverse and healthy gut microbiome have a more efficient metabolism and lower risk of weight gain. Fermented foods such as yogurt, kefir, kimchi, and sauerkraut, along with fiber-rich foods like fruits, vegetables, and whole grains, can promote a healthy gut microbiome. Additionally, limiting processed foods, artificial sweeteners, and excessive antibiotic use can help maintain gut balance and support metabolism.
Conclusion
Metabolism undergoes natural changes as we age, slowing down after age 60, but remaining fairly steady until then. Despite these changes, it is possible to effectively maintain or speed up metabolism through proper nutrition, regular exercise, controlling body temperature, and optimizing sleep. It is important to realize that metabolic rate is influenced not only by biological processes, but also by lifestyle. Keeping active and eating a healthy diet at any age can help slow age-related metabolic changes and improve health and quality of life.
