It’s no mystery that people want to live longer. Ponce De León sought the Fountain of Youth. King Arthur sought the Holy Grail. And today researchers seek to make us live longer through science.
But living longer isn’t glorious if your brain quits working before you die. Life expectancy for humans is longer than ever. Yet we still experience dementia and Alzheimer’s.
The race is on to find a cure for brain diseases. Until we do find an actual cure, the focus has to be on preventing dementia and Alzheimer’s.
Today we’re going to examine one study that suggests diet could be the key.
1. What Causes Brain Degeneration?
We’re good at talking about heart health. We label heart-healthy foods. We talk about cholesterol. But we rarely talk about brain health.
And if you’re merely looking at what kills us, this approach makes sense. Heart disease is the leading cause of death, after all.
Some in the health field feel it’s not enough just to focus on death. While still not popular to talk about, quality of life is gaining traction as an area of health study. And we’re finding out some interesting things about brain degeneration that might enhance quality of life.
Each time you learn something new, you break your DNA. But don’t worry, your body knows how to repair the damage.
Neurons in the brain must break their own DNA to initiate the transcriptional program that allows learning and memory function. The cells quickly repair the damage and keep functioning.
The problem comes when our bodies age and slow down. The process of repairing DNA slows down as well. Eventually, our bodies can’t keep up the repairs and we accumulate damage over time.
Since this damage is in the neurons that process memory and enable learning, we see symptoms like memory loss, anxiety, and depression.
Researchers still don’t fully understand what causes the body to slow down its repair mechanisms. But they have found that diet is one way to reduce the damage we see in the brain during aging.
2. Low-Calorie Diets Aid in Mice Longevity
Recent studies show that, at least in mice, a severe calorie restriction aids in longevity. There is improvement in learning and memory in old rodents.
How much did they reduce the diet of mice? 10-50%. They also tried extended periods of fasting.
Scientists then used various common tests including the Morris water maze, Barnes maze, and object recognition. The tests determine how well the mice are learning and retaining information.
They found that mice who experienced the severe calorie restriction did better at the various mazes. Their times improved as well as their ability to learn easier pathways through the maze.
They tested these mice for one year and found that the best calorie restriction percentage was 40% (they found decent results at 20%). If you translate that to a common diet of 2500 calories and you’re looking at only 1500 calories a day.
For most people, such calorie restriction won’t be tenable, especially in developed countries where food is so bountiful. So scientists are looking for other ways to get the same diet effects without severely restricting calories.
3. The Opposite of Keto (Low Protein + High Carbs!)
The keto diet, eliminating carbohydrates and increasing protein and fat sources, is a popular and often misunderstood diet. Many claim it’s changed their lives for the better. Just about all of the popular diets including Weight Watchers and Nutrisystem subscribe to the high protein / lower carb
But as it turns out, the opposite of the keto diet is what might reverse brain degeneration in humans.
When researching how calorie restriction might negate the effects of brain degeneration, scientists looked at five areas: Cardiometabolic health, hippocampus RNA expression, nutrient sensing pathways, dendritic spine density, and cognitive function during aging.
They found a diet that improves all of those areas at once without severely restricting calories. It’s a diet of low-protein and high carbohydrates.
So, runners rejoice! Your pre-race carb-loading pasta-fest is also protecting your brain health.
How Did They Figure it Out?
For a long time, we’ve known that this diet increased longevity. In fact, in many “blue zones” such as Okinawa where more people live to see 100 than any other place on the planet people eat a low-protein, high-carb diet. Until the calorie restriction studies, scientists hadn’t considered turning to a low-protein, high-calorie diet for improved brain health.
In the study, they used pure starch-derived complex carbohydrates like what you find in whole grain rice. And they used casein protein, which is in dairy.
To make sure they could see the results of calorie restriction first hand for comparison, they restricted another set of mice to 20% reduced calorie diet. They then studied the hippocampus or the area of the brain related to memories. Specifically, they looked at RNA expressions in mice brain cells.
They used the same maze and memory tests of the previous calorie restrictions studies.
What Did They See?
The hippocampus is where we see the brain deteriorate first with diseases like dementia and Alzheimer’s. But the low-protein, high-carbohydrate diet seemed to improve hippocampus health. In fact, some areas showed greater improvement than the calorie restriction diet.
This could be yet another reason to question diets like keto that drastically cut carbs. (especially good carbs like veggies!)
The Best We Have Now
There are no pharmacological treatments for dementia. We can cure various cancers or fix a heart, but we can’t medically cure dementia.
Diet and lifestyle seem to be our only tools right now to combat this ugly side of aging. Other lifestyle changes could help with dementia as well.
Continued education in later life seems to help with dementia. People with low blood pressure also are less likely to experience dementia. But diet seems to be top of the list when it comes to improving brain health.