Losing weight won’t make you happy

Weight loss significantly improves physical health but effects on mental health are less straightforward, finds new UCL research funded by Cancer Research UK. In a study of 1,979 overweight and obese adults in the UK, people who lost 5% or more of their initial body weight over four years showed significant changes in markers of physical health, but were more likely to report depressed mood than those who stayed within 5% of their original weight. The research, published in PLOS ONE, highlights the need to consider mental health alongside physical health when losing weight. Clinical trials of weight loss have been shown to improve participants' mood, but this could be a result of the supportive environment rather than the weight loss itself, as the effects are seen very early on in treatment and are not related to the extent of weight loss. It's important to note this new result does not mean that weight loss necessarily causes depression directly, as depression and weight loss may share a common cause. However, it shows that weight loss outside the clinical trial setting cannot be assumed to improve mood and raises questions about the psychological impact of weight loss. The data came from the English Longitudinal Study of Ageing, a UK study of adults aged 50 or older, and excluded participants with a diagnosis of clinical depression or a debilitating illness.