American researchers have found that women over 40 should not deliberately lose weight. If they go on a diet and lose 4.5 kilograms, they will look four years older than women of the same age. In contrast, plump cheeks and soft facial features will make women look young. The results of this study are published on the website of the American Journal of Plastic and Reconstructive Surgery.

Fat people are not old.

Researchers tracked nearly 200 pairs of female twins in two years, observed their "appearance age" and compared their body mass index (BMI). Researchers say that twins share the same genes, so the difference in appearance is mainly influenced by lifestyle.

The calculation method of body mass index is weight (kg) divided by the square of height (m). This value is normal between 18 and 25. If it exceeds 25, it is overweight, and if it exceeds 30, it is obese.

Bahaman Guyuron, a researcher at case western reserve university in the United States, said that twin sisters whose body mass index values differ by more than 4 were divided into two groups. Among women over 40, the group with higher body mass index "looks 2 to 4 years younger".

According to the website of plastic and reconstructive surgery, this means that people of the same height, if they are 4.5 kilograms lighter, may have to pay the price of "old" for two to four years.

Lose weight and show old age

Rajiv Grover, secretary of the British Association of Aesthetic Plastic Surgeons, said that it is not the wrinkles and lines on the face that make people look old, but the "face change".

Grover said that most people's cheeks began to relax around the age of 38. This is especially obvious for people who often diet to lose weight.

He said that people go on a diet to lose weight in order to keep fit, which leads to weight fluctuation and facial fat fluctuation. This makes the subcutaneous ligament loose and tight, and the nasolabial groove deepens.

He warned that dieting may make women slim, but it "will definitely accelerate facial aging".

"The more fat on the face, especially on the cheeks, the younger a person's face looks." Grover said.

However, the researchers also reminded that this does not apply to women under 40. For young women, obesity undoubtedly makes people "look old".

Other factors

In addition, the researchers also found that shocks such as divorce will also have an impact on a person's "appearance age". In most cases, married and single people look younger than divorced people.

Gu Youlong said: "Among the twin sisters, the divorced one looks older than the unmarried one 1.7 years old."