Calorie Restriction Prevents Negative Effects of Aging (and helps you live longer)
By the wlr team
Key takeaways
- 57% of age-related changes in cell composition seen in the tissues of rats on a normal diet were not present in the rats on a 30% calorie restricted diet
- Increase in the inflammatory response during aging repressed by caloric restriction
If you want to reduce levels of inflammation throughout your body, delay the onset of age-related diseases and live longer—eat less food.
That’s the conclusion of a new study(1) by scientists from the US and China that provides the most detailed report to date of the cellular effects of a calorie-restricted diet.
“We already knew that calorie restriction increases life span, but now we’ve shown all the changes that occur at a single-cell level to cause that,” says Juan Carlos Izpisua Belmonte, co-corresponding author of the new paper.
Aging is the highest risk factor for many human diseases, including cancer, dementia, diabetes and metabolic syndrome.
Caloric restriction has been shown in animal models to be one of the most effective interventions against these age-related diseases. And although researchers know that individual cells undergo many changes as an organism ages, they have not known how caloric restriction might influence these changes.
The Study
Belmonte and his collaborators compared rats who ate 30 percent fewer calories with rats on normal diets.
Their diets were controlled from age 18 months through 27 months. (In humans, this would be roughly equivalent to someone following a calorie-restricted diet from age 50 through 70.)
At both the start and the conclusion of the diet, Belmonte’s team isolated and analyzed a total of 168,703 cells from 40 cell types in the 56 rats.
The cells came from fat tissues, liver, kidney, aorta, skin, bone marrow, brain and muscle.
The Results
- Many of the changes that occurred as rats on the normal diet grew older didn’t occur in rats on a restricted diet.
- Even in old age, many of the tissues and cells of animals on the diet closely resembled those of young rats.
- Overall, 57 percent of the age-related changes in cell composition seen in the tissues of rats on a normal diet were not present in the rats on the calorie restricted diet.
“This approach not only told us the effect of calorie restriction on these cell types, but also provided the most complete and detailed study of what happens at a single-cell level during aging,” says co-corresponding author Guang-Hui Liu, a professor at the Chinese Academy of Sciences.
- Some of the cells and genes most affected by the diet related to immunity, inflammation and lipid metabolism.
- In brown adipose tissue, a calorie-restricted diet reverted the expression levels of many anti-inflammatory genes to those seen in young animals.
“The primary discovery in the current study is that the increase in the inflammatory response during aging could be systematically repressed by caloric restriction” says co-corresponding author Jing Qu, also a professor at the Chinese Academy of Sciences.
“People say that ‘you are what you eat,’ and we’re finding that to be true in lots of ways,” says Concepcion Rodriguez Esteban, another of the paper’s authors and a staff researcher at Salk. “The state of your cells as you age clearly depends on your interactions with your environment, which includes what and how much you eat.”
Would you swap 30% less calories for 57% less aging?
Aside from the obvious body weight benefits, restricting calories is emerging as a major factor in keeping healthy as we age.
We previously covered two studies that shed light one this. Interestingly, both showed benefits at lower levels of calorie restriction - 12% and 25%.
Many people could make a 12% reduction in daily calories without too much trouble. Here's the articles:
Cutting Calories by 12% Protects Health, Reduces Weight and Body Fat
Restricting Calories Can Be Good for Health Even at a Relatively Low BMI
How many calories would you need to cut?
Based on current guidelines, on average, women need 2000 calories a day, men 2500. The table below shows how many calories you could eat at the three levels of calorie restriction.
| Women | Men | |
| Normal Calories | 2000 | 2500 |
| Less 12% Reduction | 1760 | 2200 |
| Less 25% Reduction | 1500 | 1875 |
| Less 30% Reduction | 1400 | 1750 |
Note: the 12% reduction level equates to around half a pound a week, 25% a pound a week, weight loss for women - a little more for men.
Here's some resources to help you make those reductions:
10 Easy Ways to Reduce Calories for Weight Loss
How to Plan Your Diet for Weight Loss
12 Ways to Cut Your Portion Sizes Without Feeling Hungry
See How Many Calories You Need
To maintain your current weight or lose weight. Get an accurate figure personal to you, plus the tools to keep track. You can try wlr free.
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