Diet or Activity? What’s Preferable for Obese Ageing Populations?

Jack Barton | 2014-08-07 04:52:23

The increasing prevalence of obesity is recognised across all populations, many individuals are looking to make lifestyle changes in order to attempt to improve their body composition and more importantly, their health and quality of life (QOL). However making numerous lifestyle changes can be extremely difficult, especially for those who have developed habits over decades. For ageing populations (no definition of ‘ageing’ here, down to your interpretation) making one lifestyle change can have significant benefits to longer term sustainability for more consistent health and QOL benefits.

Many individuals perceiving themselves as ageing, that may have been told by their GP that they are ‘obese’, are looking for the greatest bang for their buck, so what really is best? Diet or activity?

A study conducted in 2011 (Villareal et al, 2011) took 107 obese adults over the age of 65 and separated them into four groups, a control group, an exercise group, a diet group and an exercise and diet group. Individuals in the diet group worked with a registered dietician creating a calorie deficit (eating less calories than you are expending) of 500-750kcal per day. The exercise group undertook 3 group based exercise sessions per week whilst consuming a diet that would maintain their weight. The diet and exercise group utilised both a calorie deficit and exercise sessions. The control group did not change their current diet or activity habits. The study lasted one year and assessed a host of measures including a physical performance test, weight loss, fat loss, exercise capacity, fall incidence, bone mineral density and many more.

As one may expect the researchers found that improvements in the physical performance tests were most significant in the diet and exercise group. However the exercise alone group showed significantly better improvements than the diet group despite that group showing no weight loss due to the maintenance of an energy balance. Interestingly the diet group showed the same weight loss as the diet and exercise group most likely due to worse adherence to dietary strategies.

A measure I found particularly interesting was that bone mineral density was negatively impacted in both the diet group as well as the diet and exercise group. This is particularly important when considering the increased likelihood of osteoporotic fractures in over 65s, however one must remember the increased force placed upon bones when carrying excess weight so there is a trade-off.

Based on the findings of the study I’d conclude that when focusing solely on weight loss then instigating a calorie deficit through diet appears most effectively. However for most individuals health and quality of life is of primary importance, the ability to move around on a day to day basis whilst remaining independent is essential, in which case increasing exercise, or as we like to call it, activity, comes out on top. Not forgetting the fact that cardiorespiratory fitness shows the greatest correlation to mortality rate providing yet further argument for increasing daily activity.

Jack Barton (Researcher, Rescon Ltd)

Villareal, D. T., Chode, S., Parimi, N., Sinacore, D. R., Hilton, T., et al. (2011). Weight loss, exercise, or both and physical function in obese older adults. New England Journal of Medicine, 364(13), 1218-1229.