We’ve written about calorie restriction and longevity many times before. Calorie restriction extends the lifespan of many different species. Researchers believe this also works for people when combined with optimal nutrition. The question is, why?
Now thanks to scientists at the Buck Institute, the answer is straightforward: They’ve discovered a fasting gene necessary for a healthier, longer lifespan and a sharper, more focused brain.
Finding a way to take advantage of this gene could help all of us live longer and healthier lives without the extremes of dieting, fasting, or excessive calorie restriction. But before we get there, let’s take a closer look at the longevity benefits of calorie restriction.
Calorie Restriction Could Add Five Years To Your Life
The most promising results from calorie restriction have seen lifespans extended by between 50 and an incredible 300 percent in species ranging from yeast and worms to mice and monkeys.
In short-term human trials, improvements seen in bloodwork suggest we could add up to five years to our lifespan by restricting calories. The trouble is, this caloric restriction is not for the food lover because it requires cutting calories by a third. For most, going hungry by cutting so many of our day-to-day calories is too much to bear to add a few years to life.
Researchers wondered if identifying why calorie restriction works could mean discovering a strategy for extending lifespans without dietary restriction in the future. This could be science's answer to the saying, "Have your cake and eat it too!"
Here's what happened: Scientists at the Buck Institute, a global leader in the field of aging, had already discovered various mechanisms involved in calorie restriction’s anti-aging mechanism. One process they were particularly interested in was how calorie restriction affects the brain.
To investigate further, they began by studying 200 strains of flies.
The Importance Of A Single Gene
For the Buck Institute study, researchers raised all the flies with different genetic backgrounds but fed them either a normal diet or one severely restricted to only ten percent of normal calories. The team identified five genes with specific variants significantly affecting longevity under the dietary restriction. Of those, two had counterparts in human genetics.
The researchers chose to study one of these genes, OXR1. This gene is known to protect cells from free radical damage, and its loss causes severe neurological defects and premature death. However, how a gene active in neurons can affect lifespan was unknown.
The Buck team conducted a series of in-depth tests to determine this. The findings showed that dietary restriction slows brain aging because OXR1 maintains the retromer.
What is the retromer? It’s a set of proteins necessary for recycling cellular proteins and lipids, or fats.
Kenneth Wilson, the first author of the research, published in the journal Nature Communications in January, explains more: “The retromer is an important mechanism in neurons because it determines the fate of all proteins that are brought into the cell."
“Diet is influencing this gene. By eating less; you are enhancing this mechanism of proteins being appropriately sorted in your cells because your cells are improving the expression of OXR1".
“When people restrict the amount of food that they eat, they typically think it might affect their digestive tract or fat buildup, but not necessarily about how it affects the brain. As it turns out, this gene is important in the brain".
“Diet impacts all the processes in your body. I think this work supports efforts to follow a healthy diet because what you eat will affect more than you know.”
Our Takeaway
We couldn’t agree more. The most important strategy for staving off the signs and symptoms of aging is to eat healthily by adopting, for instance, a plant-rich diet. That should naturally restrict your calorie intake. For those who want to go further but not as far as restricting calories by 30 percent, Buck Professor and senior study author Pankaj Kapahi suggests intermittent fasting.
