11/08/2026
The Hidden Difference Between a Good Supplement and a Waste of Money: Why I’m Fussy About the Supplements I Prescribe
Walk into a pharmacy, health shop or scroll online and you can now buy supplements for almost anything. Magnesium for sleep. Creatine for strength and healthy ageing. Fish oil for inflammation. Broccoli sprouts for detoxification. Herbs for hormones, stress and menopause.
But having the right ingredient written on the label doesn't necessarily mean you are getting the right product.
As a naturopath and medical herbalist with over 20 years of experience, an important part of my job isn't simply deciding which nutrient or herb might help. I also consider quality, source, form, dose, manufacturing, stability and bioavailability.
Sometimes the differences between products are enormous.
CREATINE: quality matters
Creatine has become incredibly popular with women, particularly during perimenopause and menopause. Recent research into women (hurrah, finally!) its potential benefits for muscle, strength, exercise performance, cognition and healthy ageing has understandably generated considerable interest.
But popularity also creates a rapidly expanding market.
Something many consumers don't realise is that supplemental creatine is manufactured through chemical synthesis, commonly using raw materials such as sarcosine and cyanamide, and the quality of the raw materials, manufacturing process and purification matter.
Poor manufacturing can potentially leave unwanted by-products such as dicyandiamide, dihydrotriazines and creatinine. Trace contaminants such as heavy metals may also potentially enter through raw materials, water or processing equipment.
This doesn't mean creatine supplements are generally contaminated. It means I want to know that a manufacturer has good quality controls and appropriate purity and contaminant testing.
Dose matters too. More isn't necessarily better, and the appropriate amount should reflect why someone is taking it rather than the latest social-media recommendation.
FISH OILS: Fish oil taught us this lesson years ago
Fish oil is a great example of why I don't choose supplements from the front of the bottle, in fact I only buy from 3 companies.
A well-known New Zealand study tested 32 fish-oil supplements and found only three contained EPA and DHA at or above their labelled quantities. Oxidation was another concern, with many products failing the oxidation measures assessed. Oxidation = rancidity. YUCK and toxic!
A later NZ investigation produced much more reassuring results, with 91% of products meeting EPA/DHA label claims. The difference between these studies is important - quality isn't necessarily poor across the entire industry.
But it reinforces why I want to know how much EPA and DHA a product actually supplies, along with its source, processing, storage and oxidation protection.
"Fish oil 1,000 mg" on the front doesn't tell me enough.
BROCCOLI SPROUTS: what's actually in the bottle?
Broccoli sprout supplements provide an even better example.
One of their most researched compounds is sulforaphane, but simply putting "broccoli sprout" on a label doesn't tell us how much usable sulforaphane someone will actually receive.
Broccoli contains glucoraphanin, which needs to be converted into sulforaphane. The enzyme myrosinase plays an important role in this conversion - and processing can damage or inactivate it.
Human studies have demonstrated that formulations with inadequate myrosinase activity can result in substantially poorer sulforaphane bioavailability. In a recent clinical study, adding a source of active myrosinase approximately doubled average sulforaphane bioavailability.
So before recommending a broccoli sprout supplement, I might ask:
• Is it made from sprouts, seeds or an extract?
• How much glucoraphanin does it provide?
• Is active myrosinase present?
• Has its sulforaphane yield actually been measured?
• Is potency verified batch by batch?
• Will that potency remain throughout its shelf life?
Two bottles can therefore both say "broccoli" while potentially delivering very different biological effects.
MEDICINAL HERBS: The same applies to medicinal herbs
The species, plant part, growing conditions, harvesting, extraction method, strength and dose can all influence its therapeutic effects. Cross contamination of raw material is common too, and not all companies will test their products. Phytomed NZ (which produce the Kiwiherb range) are an example of a company that prioritises testing and quality.
This is also something that concerns me when reading herbal research.
We regularly see studies of medicinal plants using preparations, plant parts or doses that don't reflect how that herb is actually used therapeutically. If herbalists traditionally use a particular root extract at a therapeutic dose, testing a small quantity of a different preparation and finding little effect doesn't necessarily tell us whether the medicine works when appropriately prescribed.
It raises an important question: how often are experienced medical herbalists and naturopaths involved when clinical trials of herbal medicines are designed?
Who determines which plant part, preparation and dosage should be studied? And who funds that research?
Negative studies shouldn't simply be dismissed because we don't like their conclusions. Good research should challenge traditional assumptions too.
But equally, a study using an inappropriate preparation or sub-therapeutic dose shouldn't automatically be interpreted as proof that the medicinal plant itself is ineffective.
True gold-standard herbal research should combine rigorous scientific methodology with a genuine understanding of the medicine being tested.
This is part of what you're paying a practitioner for
You don't need to pay a practitioner to tell you that magnesium may help sleep, creatine is being researched in menopause or omega-3s can be beneficial. You can find that information online in seconds.
The expertise lies in determining whether it is appropriate for you – and then selecting the right substance, form, source, quality and therapeutic dose.
I spend considerable time researching the supplements and herbs I use clinically: looking at manufacturers, formulations, ingredient sourcing, research, testing and therapeutic dosing.
Sometimes practitioner products cost more, because you are paying for quality, or higher therapeutic dosages based on clinical research, and sometimes less excipients, binders and filler agents in them (which can be toxic).
The key is understanding what is actually in that bottle, whether it can deliver what the label promises - and whether it's the right thing for you.
Because the name on the front of a supplement bottle is only the beginning of the story.
Invest in your natural health experts to guide you along. We naturopaths and New Zealand Association of Medical Herbalists are the unsung heroes, and we need your support to thrive.
Shine bright,
Nic
