Small Changes But Big Consequences: The Health Impact Of Modest Calorie Reductions

There has been growing research evidence for several years now that reducing your calorie intake may lead not only to weight reduction, but also to less inflammation and even the slowing of biological aging. Of course, for older adults, fewer calories need to be balanced with sufficient nutritional intake and support of strength and muscles, so any dietary changes you are considering should be discussed with your primary care provider. The key question is, can older adults cut calorie intake while maintaining their health and well-being? Increasingly, the answer to this is that calories can be cut without compromising health. 

You may recall that in an earlier agebuzz post, we reported on findings from the CALERIE study, a large, multi-year study designed to examine the impact of calorie reduction on aging. While that earlier study found that calorie reduction did lead to the slowdown of biological aging, the study protocol for reducing calories by 25% was not sustainable for most participants. New research, however, demonstrates that even with much less calorie reduction in your diet (from a 10-15% reduction), important biological benefits can still be achieved. According to a new study from the CALERIE trial published in Nature Aging, a calorie reduction of only 12% was still able to slow biological aging by 2 to 3 %, which is comparable to the result you would achieve if you stopped smoking. Moreover, even this more moderate calorie restriction led to reduced inflammation in participants and improved muscle health, without compromising their nutritional health. Perhaps what’s most important about this research is that this level of calorie reduction is much more achievable for an older adult- it’s essentially the equivalent of forgoing about 200 calories a day- maybe that afternoon ice cream scoop or the chocolate muffin you eat as a mid-morning snack. In essence, this is a doable ask for many, and results in big benefits as you get older. For more on the biology and details of this new study, rethink that Snickers bar and click here. Another recent study published in The American Journal of Clinical Nutrition also came to similar conclusions, that extreme calorie restrictions are not necessary, and valuable health results from even a 10% caloric reduction can be achieved.

The studies cited above took place over 2 years and involved human clinical trials. A much longer study involving monkeys looked at the impact of a 30% calorie reduction over 20 years. Published in Aging Cell, this study found that such a significant calorie restriction did slow down indicators of brain aging. What’s interesting and valuable about this study is that it demonstrates in a mammal more closely resembling a human (as opposed to a mouse) that caloric reductions over an extended period of time can bring about significant brain health benefits. While it’s not likely that most humans, especially older adults, could reduce their calorie intake by 30% (which could cause such serious health risks as muscle loss, malnutrition, or fatigue), the study does seem to validate the benefit of calorie reduction, even as it was utilized in a less restrictive manner in the CALERIE clinical trials. It’s long-term evidence that calorie restriction may not only provide physical benefits but may also protect against brain aging, as this monkey study concluded.

Bottom Line? With a bit of restraint and a modest swapping of some of the items on your plate, you can achieve real health benefits while remaining satisfied with what you’re eating. So check in with your doctor, don’t worry about feeling “hangry,” and consider some of the suggested strategies for calorie reduction here.