Everything we think we know about our metabolism could be wrong.
A new study suggests that people's energy consumption has been misjudged until now. And that the metabolism slows down with age. There is a widespread assumption that people gain weight after their 20s because their metabolism slows down. Women in particular are said to have an even slower metabolism and the problem is exacerbated by the menopause.
All wrong, according to this study. With the data of 6,500 people, between 8 days and 95 years old, they found out that there are four phases of life from the point of view of metabolism and that women and men function very similarly here.
The scientists Leanne Redman and Rozalyn Anderson call the findings groundbreaking and say that some findings from the past must be revoked as wrong. Dr Samuel Klein, who was not involved in the study, takes a more sober view: according to him, weight gain still has to do with people eating more than they consume.
The challenge with metabolism is the cost of the studies and the small number of participants. However, through the collaboration of six different laboratories over a period of 40 years, insights were gained. All the labs used the same gold standard for measuring metabolic rate: measuring calories burned by exhaling carbon dioxide. The scientists also correlated height, weight and fat percentage to have a robust comparison between short and tall people.
There are four phases in a person's life:
- In childhood, the metabolic rate is highest and up to 50 percent higher than in adults.
- After the first year of life, the rate decreases by about 3 per cent per year until the age of 20.
- 2. from 20 to 60 it remains stable.
- From 60, it decreases 0.7 percent per year.
No differences were found between men and women. There are, of course, large individual differences of up to 25 per cent upwards or downwards with regard to metabolic rate. However, these do not change the pattern described above.
Of course, the study also opened up new questions. For example, what distinguishes people with fast and slow metabolic rates and whether there is a connection with obesity.
No major differences were found in menopausal women or people over 40. From 60 to 95, however, a drop of 20 percent was recorded. This slowdown in metabolism means poor organ function and may explain the emergence of chronic diseases.
So there are two milestones in an adult's life: 20 and 60.
But don't worry, the fewer calories burned at rest can be compensated for by exercise.