Supplements are booming – but the science is lacking

Health is high on the agenda for consumers – and so is confusion.

As a nutrition scientist with over 25 years’ experience running clinical trials, I find myself constantly fielding questions from friends, family and people online about which supplements actually work.

To be honest, even I often don’t know the answer. There seems to be a new ‘silver bullet’ every month that promises the world to consumers. The supplement and functional food aisles have ballooned, filled with bright packaging and bold claims, whilst the science behind many of those products simply hasn’t kept pace.

It’s easy to see how we got here. Most of us are stretched – eating on the go, juggling work and home life, and trying to do the right thing for our bodies when we remember and our budget and time allows. All of this is playing out in the middle of an incredibly noisy wellness economy that’s cluttered with contradiction, fads and a big dose of “nutri-nonsense”.

On top of this perfect storm, we have the rise of wellness influencers peddling everything from weight loss teas to miracle pills. People understandably want a quick fix and it’s hard to tell the fact from the fiction.

The rise of supplements

Meanwhile, the UK supplement market is booming – now worth over £600m a year. But we’ve reached a tipping point: the gap between what’s being sold and what’s supported by robust scientific evidence is widening.

Let me be clear: supplements do have a role for specific groups. Folate is essential for women trying to conceive. People with iron-deficiency anaemia need iron supplements. Older adults may benefit from a multivitamin, and those following a vegan diet often need B12. These are real needs, grounded in clinical evidence.

But for most people in the UK, deficiencies in vitamins and minerals are rare. Our population is rarely lacking in zinc or vitamin C – yet we continue to see products marketed as ‘immune boosters’ with no evidence to support their efficacy.

More isn’t always better. In some cases, it can even be harmful. For example, excess vitamin A has been linked to negative health effects. We’ve seen the impact in children in the US, where misinformed parents are opting for vitamin A over vaccinations, resulting in liver damage.

So, why do these products persist? Because they sell. They offer a sense of control and an ‘easy fix’ in a world where eating well can feel increasingly difficult. But if we’re serious about supporting public health, the supplement sector needs to evolve, not just expand.

Nutritional needs

The real nutritional gap, for most of us, isn’t about vitamins, it’s fibre and plant diversity. Around 95% of us don’t meet the recommended fibre intake and we’re not getting the variety of plants our bodies and gut microbes need to thrive.

This is where supplements can play a more meaningful role for some people: helping them increase their intake of underconsumed but beneficial diversity of fibre from different sources, in a convenient and evidence-based way.

When we developed Zoe’s Daily30+ to meet this need, we tested it in a randomised controlled trial, comparing it to two control groups. Crucially, we undertook this clinical trial before launching the product – not after, as others do. The results were promising. Participants saw improvements in gut health, mood and energy within a matter of weeks.

This kind of rigorous testing is still rare in the supplement world, but it shouldn’t be. Consumers are more health-literate than ever, and increasingly (and rightly) demand transparency and evidence. Meeting that demand means moving away from vague promises and towards clear, honest science.

The next chapter for the supplement industry must focus on function, not fantasy – on delivering the nutrients and bioactives people are actually lacking, not the ones they aren’t, or the ones which are trendy on social media. This means putting whole plants, fibre, healthy fats, bioactive compounds and clinically tested formulations at the centre of product development, not as an afterthought.

Professor Sarah Berry, chief scientist at Zoe