Introduction
In this first week of bringing you some of the latest health research we investigate the age old question of which is more effective – diet or exercise? The health article for this week is an extensive review of 117 studies that examine and compare the benefits of exercise versus calorie restriction (a diet) on reducing that all important visceral abdominal fat – that is the dangerous fatty tissue that sits around our organs. The findings of this review were very positive towards exercise, and demonstrated that although dieting is more effective for weight loss, it isn’t as effective as exercise for reducing visceral abdominal fat. Therefore it seems that a decent proportion of the weight loss through dieting alone must be from fluid and muscle loss, which is not optimal. Therefore the recommendations are still for a combination of exercise and healthy diet – surprise surprise!
Article Title
A systematic review and meta-analysis on the effects of exercise training versus hypocaloric diet – distinct effects on body weight and visceral adipose tissue, by Verheggen, Maessen, Green, Hermus, Hopman & Thijssen, in Obesity Reviews (2016)
Background
Weight loss is achieved by altering the balance between the amount of energy consumed (EC) and energy expended (EE). Weight loss can therefore be achieved either by reducing EC, increasing EE, or a combination of both. This is commonly called dieting, exercising, or combining both diet and exercise. Most people tend to instinctively identify diet as the primary way to lose weight, although many also include exercise as an extra tool. Even so, there are widely varying opinions regarding the optimal ways to lose weight and experts have made widely diverging recommendations about the best diet, exercise program, or combination. Weight loss requires an energy deficit. An energy deficit occurs when EC is smaller than EE (so the energy balance is negative). In contrast, an energy surplus is where EC is larger than EE (so the energy balance is positive). When there is an energy deficit for a sustained period of time, people lose weight (usually mostly from fat reserves) while when there is an energy surplus for a period, people gain weight (again, mostly stored as fat).
Conclusion
The researchers concluded both aerobic exercise and diet reduce visceral adipose tissue, but in direct comparisons exercise shows a trend to a bigger reduction in visceral adipose tissue, while diet shows a trend to a bigger reduction in bodyweight. Put simply, diet alone and you can lose weight, but if reducing the dangerous fat around your organs is important to you then exercise is also required for more effective results.