A guide to supplements: how to decide what to take, what to skip, and how to know if they’re working for you.
Supplement use in the Nordics is among the highest in Europe. Most people already have a routine — four or five products, sometimes more — assembled from a podcast, a friend, a search result, a clinician, or increasingly an AI chatbot. What's striking isn't that people supplement. It's that almost nobody has been told whether they actually need the ones they take — or, more importantly, whether those supplements are even working.
Why it matters which ones you take
Supplements can genuinely fill gaps in a diet. You might follow a pattern that excludes whole food groups. You might carry a training or work load high enough that food alone struggles to keep up. There are plenty of legitimate reasons to have a real gap. But a gap has to be demonstrated, not assumed. For several nutrients, a blood test settles the question outright. For most of the rest, the decision rests on assessment rather than measurement — weighing likely benefit against real risk, in the context of your diet, your medications, and your health status. Knowing which category you're in saves money, avoids harm, and stops you from "correcting" a deficiency that was never there — which is its own way of creating an imbalance.
How to approach supplementation
Treat food as the first intervention. Total dietary pattern outperforms isolated compounds for nearly everything, partly because of the food matrix — nutrients in food arrive alongside the fibre, fats, and co-factors that affect how they're absorbed and used. A supplement stack sitting on top of a poor diet is an expensive way to underperform. The exception is a severe, confirmed deficiency, where a supplement may genuinely be needed to bring levels back up. Even then, it's worth asking why the deficiency happened in the first place — when one deficiency shows up, there are often several more that simply haven't been tested.
Define the problem you're trying to solve - and measure the result. For example: normalizing elevated blood lipids within six months, reducing inflammation from an autoimmune condition within ten months, normalizing elevated blood sugar within five months, or gaining 0.5 kg of muscle within three months. If you're taking a supplement for general "optimization" without a defined target, it becomes very difficult to know if it's doing anything. Many supplements are marketed around longevity or optimization, but very few actually deliver on that promise, this is a view formed from years of reviewing blood work.
Do the right testing. Blood testing has the strongest evidence when it comes to assessing nutritional status. Iron status, vitamin D, B12, folate, zinc, and omega-3 are some of the markers worth testing, alongside blood sugar, blood lipids, and inflammatory markers. If your iron levels are already good, there's no real need to supplement iron — and the same logic applies to most other nutrients. Through the right testing the organ function can also be addressed such as kidneys, liver, thyroid etc. and this can also be used in order to determine which supplement might be right for you.
Get the right interpretation. Have the full picture read by someone qualified. An individual result is easy to find and hard to interpret in context — you might not have an outright deficiency but could be close to one, or you might have levels that are too high and need correcting. Interpretation is the part that actually changes decisions but to also go the root cause of addressing your nutritional status.
Account for genetic differences. Some individuals need to pay closer attention to certain nutrients because of their genetics — the MTHFR gene is one example.
Review your medications first. Several commonly prescribed drugs materially affect micronutrient status, and several popular supplements interact with common medications. This is arguably the single most valuable step, and it should come before anything is purchased.
Check for interactions and absorption between the supplements themselves. Not all supplements are meant to be taken together, and some work better with food, others without. I have seen many cases where the wrong supplement recommendations have been given and it has lead to patient getting other deficiencies and dealing with other problems.
Consider the quality of the supplement. Not all supplements are the same — the form, the ingredients, and what's actually in the product can make a significant difference.
Retest rather than assume. If you supplement at meaningful doses over several months, measure again. Correction is the point; indefinite supplementation without re-measurement is not. This ties back to knowing exactly what you're taking the supplement for. It's also worth checking liver status, since some supplements carry more risk than others.
Be sceptical of precision without personalisation. A supplement chosen from general information about you is still a guess — just a more expensive one.
So which ones should you take?
There's no list that answers this for everyone, which is why the honest answer starts with nutritional and medical assessment — understanding exactly what you need, rather than reaching for a general product or a one-size-fits-all recommendation. Single supplements rarely move the needle on their own, and the ones that do can shift something else in the process — so if you care about your body and health then the real question is never "is this supplement good?" but "does this fit my needs, is it right for me, and is it actually working?". At Vilya Health, personalized nutrition is the whole approach, not just a feature of it. That means working from your full picture — not only which supplements, but the dosage, the form, the quality, the timing, and the interactions and synergies between them — guided by a clinical nutrition expert.
