According to a new study at the University of Helsinki, having a personal "ideal weight" does not aid weight loss. Most young women and nearly half of young men aged 24 would like to weigh less than they do. A decade later, only one in five women and one in seven men is at or beneath the previously defined ideal weight.

“People tend to set unrealistic ideal weights, but these ideals do not help them lose weight in the long term,” explains researcher and nutritionist Ulla Kärkkäinen. “Among women in particular, the ideal weight tends to be significantly below a healthy weight, and cultural and healthy weight standards often conflict.”

This study is part of the extensive FinnTwin 16 study, involving more than 4,900 young Finnish men and women. The test subjects answered questions on their body weight and ideal weight aged 24 and again a decade later, aged 34.

Most subjects were unhappy with their weight at 24. However, men tended to be more realistic in estimating their ideal weight: on average, the 24-year-old women weighed 61.1 kg and set their ideal weight at an average of 3.9 kg below that. Men weighed 77.1 kg on average and set their ideal weight at 1.2 kg less.

The women who were happy with their weight at the outset were almost underweight, with body-mass indexes around 19. Of subjects categorised as “normal weight” at age 24, only 13% of the women and 20% of the men were happy with their weight.

Over the ten-year period, the ideal weights of both women and men approached their actual weight.  Regardless of the ideal weight determined at the beginning, nearly all subjects gained weight during the ten years. Women gained an average of 4.8kg and men 6.3kg.

“As genetics is a major factor in body weight and our living environment encourages weight gain, weight management and weight loss often prove challenging,” Kärkkäinen states. 

The results prove that a clear majority of young adult Finns are unhappy with their weight. Even though dissatisfaction with the body and its weight is common, it is far from harmless.

“Previous research has indicated that dissatisfaction with body weight increases dieting, which in turn makes the person more likely to gain weight in the long term. To avoid this harmful chain of events, it is important to promote a positive body image and to communicate more realistic weight ideals," Kärkkäinen says.

In addition to dieting, a negative body image is associated with depression, low self-esteem, low life satisfaction, eating disorders and unhealthy weight management attempts.

Conducted under Associate Professor Anna Keski-Rahkonen, the study has been published in the journal Obesity.


Further information:

Ulla Kärkkäinen, MSc, Registered Dietitian, doctoral student, University of Helsinki

Ulla Kärkkäinen, Linda Mustelin, Anu Raevuori, Jaakko Kaprio, Anna Keski-Rahkonen: Ideals vs. reality: Are weight ideals associated with weight change in the population? Obesity, 3 February, 2016