From the Institute for Optimum Nutrition:

People who spend time tending their gardens know how it makes them feel happier and helps to keep them fit. Now, a new study from the University of Utah has shown that gardening could help you to stay trim, too. [*] Green-fingered women were a dress size smaller on average, while men who tended an allotment were around a stone lighter.

The researchers compared the body mass indexes (BMI) of 198 participants in community gardening projects in Salt Lake City with those of their neighbours, siblings and spouses, after adjusting for gender and age. While all the people tested had access to the same leisure facilities, such as parks, and had a similar economic status, the gardeners were clearly thinner. The results showed that men were 62 per cent less likely to be overweight or obese than their non-gardening neighbours and that a man 5ft 10in tall was likely to be just over a stone lighter. Similarly, women gardeners were 46 per cent less likely to be overweight or obese and a 5ft 5in tall woman who gardened was on average 11lb lighter than her non-gardening neighbour, which equates to around a dress size.

The study found that these differences could not be explained away by good genes, as non-gardening brothers and sisters were not as trim. However, the husbands and wives of gardeners appeared to benefit from a “halo effect” of their spouse’s activity by having lower than average BMIs. Gardening is likely to aid weight control through aerobic exercise, vitamin D from sun exposure and eating home-grown produce. Gardeners might also tend to be more health conscious in other ways, too, and so may get further benefits from exercise and a balanced diet, beyond those afforded by their gardening activities alone.

Reference:

[*] Zick CD, Smith KR, Kowaleski-Jones L, Uno C, Merrill BJ (2013). Harvesting more than vegetables: the potential weight control benefits of community gardening. Am J Public Health Apr 18 (Online ahead of print).