Of course not. Real malnutrition lead to bad health. Prone to disease, shortened life span to name a couple.
Mild malnutrition may be OK.
Maybe not
Do Low Calorie Diets Help You Live Longer?
"Cutting calories from the diets of many animals dramatically increases their life span, leading some people to try to extend their own lives in the same way."
There is a big difference between bad malnutrition and a reduction in calories. Our population could use a reduction in calories.