For a long time, it was believed that after the age of 20 your metabolism drops dramatically – making it difficult to lose weight and stay fit. But the recent study showed that our metabolism – also known as energy expenditure – remains relatively constant between the ages of 20 and 60, before decreasing at older ages.
The researchers looked at existing studies on energy expenditure from 29 different countries. In all, they studied data on 6,400 people from birth to 95 years of age. Each study measured energy expenditure using a method called Doubly named water. This makes the participants drink a special type of water, in which a safe radioactive label has been added. The tag identifies the hydrogen and oxygen present in the water, allowing researchers to track how quickly the body processes both. Then urine samples are taken from each person to track the rate at which they travel through the body. This gives researchers an accurate measurement of a person metabolic rate The amount of energy they used in the day.
The analysis showed that energy expenditure (metabolism) increased rapidly from birth up to one year. Thereafter, energy expenditure gradually decreased until the age of twenty, and then became stable until the age of sixty – even during pregnancy. After 60 was when energy expenditure began to decline. These findings held true even when the researchers took into account various factors — such as physical activity and body composition (how much fat or muscle a person has and how much they weigh) — that can affect a person’s metabolism.
This study builds on our understanding of human metabolism. Knowing how our metabolism may (or may not) change during our lifetime can be important to knowing how to treat diseases – such as obesity, diabetes, heart disease, and even some types of cancer.
One problem with the study results, however, is that it did not take into account the amount of energy a person was consuming. Many people still see their weight increase as they age, even though their metabolism remains relatively constant throughout their lives. This indicates that weight gain is not the result of a slowed metabolism. Instead, it is more likely to be due to eating more food (energy) than the body uses.
Increase energy and weight
Metabolism is influenced by many factors – including The amount of food we eat, how much physical activity we get, weight, and whether we have a lot of muscle. Metabolism can also affect how we get energy from foods. For example, when we We eat more than we needThe body is more likely to use the carbohydrates and protein from these foods as fuel, and store fat – which leads to weight gain. Overweight and obesity are both linked to a metabolic rate caused by taking in more energy than we use.
With so many things to keep track of, it can be difficult to understand how best to manage one’s weight. This is the reason for creating experts National recommendations The number of calories people of all ages and activity levels should have. These recommendations are made using data on energy expenditure – rather than energy consumption. This is because it is believed that measuring expenditure is more accurate than measuring energy intake, which is usually done by asking people to self-report what they eat each day.
But the problem with using data on energy expenditure is that these recommendations are made with an average value – so what works for some may not work for everyone. For example, some inactive people may need to eat less food than the guidelines recommend. This may also be why we see such a mismatch with energy expenditure levels and energy intakes reported in British adults. fact, some studies They suggest they eat well less than the daily recommendations – yet we’re still seeing more people Overweight and obesity in the UK every year.
Why people seem to eat less than national recommendations could be due to a number of reasons. For example, research on energy intake shows that some participants may wrong report How much do they eat per day in surveys. The lack of reporting may not be the whole story. Even apps that Measuring the amount of food It also details giving lower values for the amount people are eating compared to the recommendations. This can make it seem like people are actually eating less than they need. Other things, such as the amount of activity and body size, can affect how much energy we need. Recommendations may not take these things into account adequately.
The promising thing about the data in this study is that it used a more accurate measure of energy expenditure with people of all ages than some studies have used in the past. This study shows us that energy needs do not appear to change significantly over an adult’s life, so these findings may be useful for adjusting our current recommendations for energy requirements. But it will be key to match the new recommendations for energy intake with how each person’s requirements differ according to their activity levels and body weight. It will also be important to develop better ways to customize recommendations, so that each person can manage their weight more effectively.
But there are still many simple ways in which a person can prevent weight gain throughout his life. Maintaining physical activity and a healthy diet are important. Although there may be some margin of error, recording how much you eat each day can help keep track of how much you eat, and can be useful for figuring out where you might need to cut back if you gain weight.
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