Harvard Doctor: The Hidden Reason Behind Low Energy, Aging, and Cognitive Decline (How to Fix It) @JimKwik
Harvard Doctor: The Hidden Reason Behind Low Energy, Aging, and Cognitive Decline (How to Fix It)  @JimKwik
Uploaded March 2026 | Updated September 2026, 3 weeks ago
Most people think feeling tired, foggy, and “off” is just what happens with age.

But what if the real issue is that your cells are running on less fuel than they used to?

In this episode of the Kwik Brain podcast, I sit down with Dr. Andrew Salzman, Harvard-trained physician, inventor, and biomedical entrepreneur, to unpack what’s happening at the cellular level when energy drops and your brain stops feeling sharp.

We break down NAD, a molecule involved in hundreds of critical reactions in the body, why it declines as you age, and how inflammation can accelerate that decline. We also talk about NMN, and why your brain is often the first place you feel the effects when cellular energy dips.

In this episode, you’ll learn:
☑️ What NAD does for energy, cognition, and resilience
☑️ Why NAD drops so significantly by midlife
☑️ How NMN works as a precursor to support NAD production
☑️ The “bathtub” model: why boosting NAD is not just about adding more, but also slowing the drain
☑️ How inflammation can drive NAD depletion through CD38
☑️ Why better cellular energy can translate into clearer thinking, better memory, and sharper focus

If you’ve been feeling like your brain isn’t firing the way it used to, your energy is unpredictable, or your focus is slipping, this episode will help you understand what’s happening underneath the surface and what you can do to support your brain at the level where performance actually starts: your cells.

👉 Comment below: What is one habit you use to protect your brain energy as you age?

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Timestamps:
03:08 What's Happening at a Cellular Level as We Age?
04:54 Aging: What We Can and Cannot Control
06:00 The Role of NAD in Cellular Health
06:54 NAD Levels Drop by Half by Age 50
07:21 How NMN Supports NAD
08:35 NAD Production vs. Depletion
10:25 The Number One Way to Avoid NAD Depletion
11:06 How the CD38 Enzyme Depletes NAD
11:37 The Myth of Passive Aging
17:53 CD38's Role in NAD Depletion and Menopause
20:29 Why the Brain Needs High Levels of NAD
22:12 Cognitive Benefits of Restoring NAD Levels
29:33 Dr. Salzman's Simple Truth for Long-Term Health

Watch more videos like this:
4 Brain Exercises to Strengthen Your Memory (and Keep Your Brain Young): youtu.be/p8QVxJXhkDgplaylist?list=PLwf_ceM-L-lNrAizBOyG_rQMkkJAEkF63
24 Books That Will Rewire Your Brain and Transform Your Life: youtu.be/DhXZg5BLKEQplaylist?list=PLwf_ceM-L-lOhmoyl0Qe2O1zLL9qOkBR0
30 Years of Brain Training Secrets in Just 19 Minutes: youtu.be/6F_FEEmzmiEplaylist?list=PLwf_ceM-L-lMzXqYH2pHu6OVg1CKE_gxS

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💊 Products Mentioned:
Wonderfeel Youngr™ NMN: tidd.ly/3Y990Xi

Connect with Dr. Andrew Salzman
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facebook.com/get.wonderfeel
tidd.ly/3Y990Xi

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Harvard Doctor: The Hidden Reason Behind Low Energy, Aging, and Cognitive Decline (How to Fix It)Stop Wasting Your Mental EnergyWork With Your Brain, Not Against ItWhy You Sleep Enough Hours but Still Wake Up Tired24 Books That Will Rewire Your Brain and Transform Your LifeUnleash The Power of Your Mind | Limitless Live 2025What No One Tells You About GrowthThe #1 Driver of Success5 Types of Wealth: Are You Playing the Wrong Status Games?You cannot pour from an empty vessel30 Minute Morning Brain RoutineHuman Intelligence Operating System
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Harvard Doctor: The Hidden Reason Behind Low Energy, Aging, and Cognitive Decline (How to Fix It)

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