The libraryMetabolism

Calorie Restriction

The deficit takes lean mass, bone and testosterone at the same time it takes the fat.

Also called Caloric Restriction, CR, Energy Restriction, Dietary Energy Restriction

A practice

Who it's forAny man dieting who thinks eating less is the whole plan.

The item

Three squares: proven in human trials. Two: a strong signal. One: early human data. Striped: the trials disagree.

Start today

  1. Write an end date on your cut today and book the lifting sessions that carry you to it.

Why it works

The effect comes less from weight loss than from the signaling state the body is in. A steady energy deficit lowers insulin and IGF-1, quiets mTOR, and switches on AMPK and autophagy. That shifts cells from growth toward maintenance and repair. That switch, not the scale, is what the longevity research is really about.

Where it fits

Calorie Restriction is a move in 6 protocols. Each one opens the plan it sits in.

What people say

Here is what doctors, influencers and men online say about Calorie Restriction, word for word.

Experts

Clinicians, authorities

  • “But calorie restriction is probably not for everyone. Our findings are important because they provide evidence from a randomized trial that slowing human aging may be possible.”

    Columbia University Mailman School of Public Health · 220
  • “Therefore, bone loss at clinically important sites of osteoporotic fractures represents a potential limitation of prolonged CR for extending life span.”

    Journal of Bone and Mineral Research (via Europe PMC) · 218
  • “The calorie-restriction intervention did cause slight declines in bone density, lean body mass, and aerobic capacity (the ability of the body to use oxygen during exercise).”

    National Institute on Aging (NIH) · 218

Gurus

Podcasts, channels, influencers

  • “Clinical trials suggest that caloric restriction may offer similar health benefits to humans, but the studies have been too short to provide conclusive results.”

    biohacker research site topic page · 218
  • “We, the authors, conclude that the evidence as it stands weakly supports the conclusion that CR modestly extends human life.”

    rationalist blog guest essay · 159
  • “These reproductive side effects are not to be taken lightly; in addition to being generally unpleasant, there are long-term consequences to maintaining a prolonged state of sex hormone suppression”

    evidence-based strength training site article · 71

Regular people

Forums, reviews, comments

  • “I've found that with time, a sensation of 'hungry' is just another sensation that my body reports - it's not an imperative to eat.”

    Hacker News thread, 216 comments
  • “CR as a life extension method in non-obese humans remains unsupported; much relevant evidence suggests that it will not work and may be harmful.”

    Slate Star Codex comment section, 159 responses
  • “Basically I felt like I was on the edge of a cold all the time. Anything activity like cycling was utterly draining. The world was very dull and grey indeed.”

    Hacker News thread, 216 comments

Cut in blocks, lift heavy through it, and set the date you stop.

Emergency: call 911.

I am not a doctor. This is not medical advice. This is self-education. Talk to a physician who has your history before you change anything.