The Type of Calorie and The Timing of Consumption Controls Healthy Aging

Numerous clinical studies have demonstrated that health and longevity are related to fasting and calorie restriction. Calories alone are not important to health and longevity, it is the type of calories one consumes, such as carbohydrates (sugars), fats, and protein.

I have extensively reviewed reports that present the results of the benefits, or lack thereof, to various types of fasting/food restrictions and types of calories:

INTERMITTENT FASTING VERSUS CALORIE RESTRICTION: WHICH METHOD REAPS GREATEST REWARDS?

INTERMITTENT FASTING FOR WEIGHT LOSS BUT OVERALL HEALTH BENEFITS MAY BE LIMITED

EATING WHEN ONE SHOULD BE RESTING IS A CAUSE OF WEIGHT GAIN

PLANT VERSUS ANIMAL PROTEIN: IS IT COMPOSITION OR TOTAL PROTEIN THAT MAKES THE DIFFERENCE

A recent, excellent review in the prestigious journal Cell Metabolism, summarizes the research findings presented at a National Institutes of Health (NIH) conference that as stated in the introduction to the manuscript, "brought together experts in calorie restriction, macronutrient composition, and time restricted feeding to discuss how dietary composition and feeding schedule impact whole-body metabolism, longevity, and healthspan."

When a calorie is not just a calorie: Diet quality and timing as mediators of metabolism and healthy aging

Individual presenters discussed results from calorie restriction (CR) studies, time restricted feeding (TRF) which is also referred to as time restricted eating (TRE), and intermittent fasting studies. Whereas, calorie restriction in non-human animal models is clearly correlated to longevity and health, these types of diets are difficult, at best, to recapitulate in humans. Nonetheless, protein or amino acid restriction diets do show health benefits in humans, but not just any protein. Proteins that are limited in the amino acids methionine and isoleucine have the most positive effects. Other presenters discussed the health and longevity benefits of ketogenic diets, but there needs to be caution as log-term adherence to a ketogenic diet has been found to be associated with fat accumulation in the liver leading to an increased potential for liver disease.

Although the paper outlines the benefits of various types of diets and feeding regimens with respect to health and longevity, the authors stress that although numerous studies in invertebrates as well as laboratory animals, such as mice, do clearly demonstrate benefits, these are not as robust in humans. Thus, there are still many unanswered questions and as yet to be determined mechanisms to attain these benefits in humans.

TAKE HOME: There is no questions that when someone eats, and what someone eat, and how much of certain foods someone eats, all exert effects that can either extend ones healthy life or lead to early mortality. And probably most significant is that a calorie is not just a calorie since it is clear that calories from different proteins (amino acids), carbohydrates, and fats or consumed at different times of day have profoundly different metabolic and molecular impacts that affect health and longevity.