There has been speculation for the past eighty years that eating less could actually allow an organism to live longer; the opposite of what most people would intuit. Therefore, research has been conducted on laboratory animals to try to understand the benefits of eating less, also known as caloric restriction (CR). Recently, this field of study received the funding and attention it needed to fully investigate this phenomenon.
The benefits of caloric restriction have proven to extend healthy, average and maximum life spans in many short-lived species, such as rats and mice. Many studies have been conducted on rats and mice, such as the 1989 caloric restriction study on monkeys at the University of Wisconsin, Madison and the newer study at the Pennington Biomedical Research Center.
One effect of caloric restriction is that it results in less oxidative damage to muscle cells, which has been linked to aging. Oxidants are produced when food is converted to energy by the mitochondria (a cellular structure). A CR diet is correlated to a decline in the accumulation of “oxidative damage” in the body’s proteins, fats and DNA.
Dietary restrictions also reduce visceral fat tissue. When a person eats less, they tend to slim down. The opposite, carrying excess body fat, has been found to be harmful to long term health in many different ways, even at modest levels of excess weight. It can increase the risk of age-related conditions such as diabetes, Alzheimer’s and cancer due to a relationship between fat cells and chronic inflammation.
CR also creates a variety of positive changes in the controlling mechanism of metabolism. CR provides a boost to the process of autophagy- the process by which cells remove damaged components in the cell in order to recycle the materials into new replacement parts. Studies have found that specific types of damaged cellular components cause problems over time that contribute to age-related decline and damage. Because of this, greater levels of autophagy may help to reduce the aging process and in turn extend life.
Overall, the studies suggest that even short-term caloric restriction can produce beneficial physiological changes, leading to improved health. And while they are making great strides in their research by testing animals, to conduct them on humans raises many ethical and methodological issues. However, this does not mean that people should be dissuaded from practicing a calorie restrictive diet. Eating better and paying attention to calories while still receiving the appropriate amount of vitamins and nutrients can achieve a caloric restrictive diet.