What is the health outcomes of caloric restriction? Is it healthy, or it is important to meet calories?
I think calorie restriction is outdated. What matters is restricting certain nutrients, not energy in general.
https://www.sciencedirect.com/science/article/pii/S0005272806000223
>Thus, methionine restriction seems to be responsible for the decrease in ROS production observed in caloric restriction. This is interesting because it is known that exactly that procedure of methionine restriction also increases maximum longevity.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1140680/
>Calories Do Not Explain Extension of Life Span by Dietary Restriction in Drosophila
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2798000/
>In other organisms, including mammals, it may be possible to obtain the benefits for lifespan of DR without reduced fecundity, through a suitable balance of nutrients in the diet.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5087279/
>The Ratio of Macronutrients, Not Caloric Intake, Dictates Cardiometabolic Health, Aging, and Longevity in Ad Libitum-Fed Mice
Meanwhile, calorie restriction is only beneficial for certain strains of mice, not all. For some, it is harmful:
https://www.ncbi.nlm.nih.gov/pubmed/19878144
>Notably, DR shortened lifespan in more strains than those in which it lengthened life.
There are some interesting studies linking calorie restriction to longevity and a reduction of inflammation.
https://www.sciencedaily.com/releases/2022/02/220210154204.htm
Of course, one would assume that higher-BMI folks would be seeing the biggest benefits, as opposed to underweight people.
It depends on your current health and weight. If you are overweight or obese then mild to moderate caloric restriction is a part of healthy weight loss, if you are in a healthy weight range then lossing more weight can negatively affect your health. For most adults 1600 calories is about the minimum that you can maintain long term without risking negative consequences like fatigue and nutritional deficiencies.