What is Nicotinamide Riboside (NR)? The NAD+ Supplement Explained

If you've spent any time down the longevity rabbit hole -- and if you're reading this, there's a fair chance you have -- you've probably come across NAD+. And if you've looked into NAD+, NR has almost certainly come up. So here's what it actually is, what the science says, and whether it's worth your money.

Nicotinamide Riboside is a form of vitamin B3. That sounds unremarkable until you understand what it does in the body. NR is one of the most direct ways to raise NAD+ levels -- nicotinamide adenine dinucleotide, a coenzyme found in every living cell that drives energy production, repairs DNA, and plays a central role in how well your cells hold up as you get older.

The problem is that NAD+ levels fall sharply with age. By your 40s and 50s you may have half the NAD+ you had in your 20s, and that decline maps pretty closely onto the things most people start noticing around that time -- lower energy, slower recovery, less mental sharpness. NR is one of the most studied ways to push those levels back up.

Why NR and Not Something Else?

There are a few ways to raise NAD+ -- niacin, NMN, and NR being the main ones. Niacin works but causes flushing, which puts a lot of people off. NMN is increasingly talked about, particularly in longevity circles, but it has less human trial data behind it than NR does at this point. NR has been through a randomised, double-blind, placebo-controlled trial confirming it effectively raises NAD+ metabolism in healthy middle-aged and older adults without meaningful side effects. That's the kind of evidence base that separates genuine research from supplement hype, and NR has it.

What Does NR Actually Do?

Four areas come up consistently in the research.

Energy is the most obvious one. NAD+ is central to mitochondrial function -- how your cells convert food into usable energy. When NAD+ drops, that process becomes less efficient, and you feel it.

DNA repair is where things get more interesting. NAD+ activates a family of proteins called sirtuins, which are involved in repairing damaged DNA. This is one of the core mechanisms researchers are now focusing on when they talk about biological ageing -- not just feeling older, but cells actually ageing at a molecular level.

Brain function is an emerging area. A 2025 randomised controlled trial published in eClinicalMedicine looked at NR's effects on energy metabolism and symptoms like fatigue and brain fog. Early results are promising, and it adds meaningful weight to what was already a reasonable evidence base for cognitive support.

Heart health rounds it out. Early data suggests NR may help reduce blood pressure and arterial stiffness in middle-aged and older adults -- not dramatically, but consistently enough to be worth noting.

How to Take NR

The most studied dose is 300-600mg per day, taken in the morning on an empty stomach for better absorption. Most people who notice a difference report it after two to four weeks of consistent use rather than straight away -- which is actually what you'd expect from something working at a cellular level rather than a stimulant. Start at 300mg and see how you get on before going higher.

The NR and Astaxanthin Combination

The Feel Supreme formula pairs NR with Astaxanthin, one of the most potent antioxidants in nature, and the logic is straightforward. NR raises NAD+ and supports cellular energy and repair. Astaxanthin protects those same cells from oxidative damage. Two of the main drivers of biological ageing -- depleted NAD+ and oxidative stress -- addressed together in one capsule.

Who is NR Most Relevant For?

Honestly, anyone over 35 who's started noticing changes in energy or mental sharpness is a reasonable candidate. If you've come across NAD+ through Huberman Lab or similar and want to know what the evidence actually says rather than what the marketing says, NR is where the clinical data is strongest right now. It's also a natural fit for anyone already taking a structured approach to longevity -- if omega-3s and CoQ10 are already in your stack, NR belongs in the same conversation.

Where to Buy NR in Ireland

We stock the Feel Supreme Nicotinamide Riboside with Astaxanthin NAD+ Booster -- 60 capsules at 250mg each, available exclusively in Ireland at Powerful.ie. Order before 4pm for same-day dispatch from Dublin.

Shop NR with Astaxanthin - €64.95

As a food supplement for adults. Not a substitute for a varied, balanced diet and healthy lifestyle. Consult your GP if you are pregnant, breastfeeding, taking prescription medication, or under medical supervision.