Karlin Frew

Karlin Frew

The Return to Cellular Vitality

Sulfur, NMN and the alchemy of energy

Karlin Frew's avatar
Karlin Frew
Nov 06, 2025
∙ Paid

Since 2020 my attention toward health has morphed a bit. I recently took a deeper dive into subjects like menopause and tried to decipher some of the information around hormones. Now I find myself a little curious about the underlying biology that keeps the body functioning well.

I’m not a scientist. I was un-encouraged from following science at school and had to take special maths classes just to get through college. Postgraduate study required learning how to work with research frameworks, which has helped a little when trying to decipher studies and create easy-to-read content. It’s a constant work in progress.

Reading research also makes it clear how quickly health ideas move. One study says one thing. Another suggests something different. Nutrition advice shifts. Supplement trends come and go. Science offers useful clues, but I tend to keep a mild degree of scepticism and try to understand the underlying biology rather than chasing every new headline.

While looking into hormones and menopause another theme kept appearing. Energy. The quiet cellular work that keeps the body functioning. Cells producing energy. Repairing tissue. Clearing metabolic waste. Building new structures.

When you start looking at biology, energy and nutrition, the topic of supplements isn’t far away. Most of us take something, and many of us take additional “health” supplements based on intuition or advice.

Walk into almost any health store and the shelves are lined with capsules promising energy, longevity and hormone balance. Step into Chemist Warehouse and the wall of bottles can feel overwhelming. I’ve stood there too, wondering if I should be taking one of everything.

Beneath all the marketing are a few substances the body already recognises and uses every day. Two practical examples are MSM (methylsulfonylmethane) and NMN (nicotinamide mononucleotide).

They are not hormones or stimulants. They take part in normal cellular chemistry.

MSM provides sulfur, a mineral required for detoxification pathways and for building connective tissue, fascia and collagen.

NMN feeds the NAD⁺ system (nicotinamide adenine dinucleotide), a co-enzyme involved in mitochondrial energy production and many cellular repair processes.

These nutrients influence how well cells produce energy, repair structures and clear by-products of metabolism. The same processes also affect how hormones are produced, used and broken down in the body.

Many foods already participate in this chemistry. Broccoli, garlic, avocado, tofu, tempeh, mushrooms and fermented vegetables all supply nutrients that interact with sulfur metabolism or the NAD⁺ pathway.

Understanding this biology simply adds clarity to habits many people already practice. Eating well. Moving daily. Resting properly.

Some cellular nutrients, particularly sulfur and the NAD⁺ system, are worth understanding a little more closely.


Why NMN & MSM Above All Others?

Tired of the mental load required to assess what supplement does what, how and when, my curiosity sparked when I was given liquid MSM for a post-operation issue.

Around the same time I kept noticing MSM and NMN appearing in conversations and being promoted online. Supplement discussions mentioned them. Occasionally they showed up in research papers too.

I’m not particularly interested in anti-ageing, partly because I’m probably in chronic denial about my age. I’m more interested in staying vital and energetically well as the years move on. Supporting clarity of mind and natural energy rhythms. Offering a little more kindness to a body that feels good and functions really well long term.

With thousands of supplements competing for attention it’s easy to lose sight of that. Most bottles promise quick results. Few explain the biology.

MSM and NMN stood out because they support processes the body already relies on. Detoxification. Tissue repair. Energy production. These processes continue throughout life. What tends to change with age is efficiency.

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