What "Medication-Aware" Supplementation Means

Written by Dr Jatin Joshi, co-founder and Chief Medical and Scientific Officer of Personally, and a researcher at the University of Oxford's Centre for Evidence-Based Medicine. I have a financial stake in this company, and you should weigh what follows with that in mind.

Think about the last supplement you bought. Somewhere between the ingredient being weighed out and the tub arriving at your door, was there any point at which anyone could have known what you were prescribed?

There was not. The tub was made before it met you. Whatever is in it was decided for a category of person, and you were the one who happened to pick it up.

That is the whole of what medication-aware means. Not a technology, not a service. A question asked before the thing is made rather than after.

The short version. A supplement made in advance cannot take your medications into account, because it did not know you existed. A formula built for you can ask what you take and screen against it first. That works in two directions: something can be left out because of what you take, and something can be included because a medication you are on is known to run a nutrient down over time. Your prescriber remains the authority on your medications. This is about what goes in the tub.

Most of the supplement aisle is made to a fixed recipe, in a batch, months before anyone buys it. That is not a scandal. It is how manufacturing works, and it is why the products are affordable.

But it does fix the order of events. The formula is finished, then it meets you. Anything about you that might have changed the recipe arrives too late to change anything.

Building a formula after the questions have been asked reverses that order. We ask what you take, and we screen against your declared medications before anything is mixed. Most brands never ask. I am not suggesting anyone is being reckless in not asking. If you are making one recipe for a hundred thousand people, the answer could not change the recipe anyway, so there would be no point in the question.

The first is the one people expect. Something is left out.

If an ingredient does not sit well alongside what you are prescribed, it is not in your formula. Not flagged with a warning on the side of the tub for you to interpret, not left in with a caution. Simply not there. This is where most of the practical value sits, and it is only possible when the formula is built rather than picked.

The second direction is less obvious and, over a long time on a medication, often matters more. Some medications are known to run a nutrient down. It is a well described part of how those drugs work in the body, it is in the prescribing information, and it is not a reason to stop taking them. Metformin and vitamin B12 is the clearest example, and there is a similar and more nuanced conversation to be had about statins and CoQ10.

A formula built after that question has been asked can take it into account. A tub made in advance cannot, because it was made for people whose prescriptions it would never see.

I want to be precise about this, because it is the part that gets overstated in this industry and I would rather under-claim it.

Screening informs what goes into your formula. It is not a review of your medicines, it is not medical advice, and it is not a diagnosis. Your doctor and your pharmacist hold the full picture, including the things a supplement company has no business knowing, and they remain the people to speak to about anything to do with your prescriptions. If your formula changes because of something you declared, that is a formulation decision, not a clinical opinion about your treatment.

What I will say plainly is that they can only account for what they know about. Telling your prescriber and your pharmacist what supplements you take is worth doing, every time, and most people do not. That habit is worth more than anything we do at our end.

The general point is easier to see in specific cases. Three pieces go through the detail:

Metformin and vitamin B12, which is the cleanest example of the second direction and the one worth a simple check.

CoQ10 and statins, where the evidence is more mixed than the internet suggests and the sensible conclusion is calmer than you might expect.

GLP-1 medications and everything else you take, where the changes are less about interaction and more about how much food is going in.

If you take anything prescribed, the question to ask of any supplement is simply whether anyone asked. Not whether the label carries a general warning, which every label does, but whether the specific thing in front of you was made with your specific list in view.

Most of the time the answer is no, and it could not have been anything else, because the tub was sealed long before you were part of the story.