The watchdog asked a panel of experts, including a dietitian, a doctor and a professor of public health medicine, to investigate the evidence behind supplements containing ingredients such as Ginkgo biloba, vitamins B and D and fish oil.
The investigators concluded there was “no robust evidence” linking the supplements to the prevention or reduced risk of dementia.
Looking also at online tests and ‘brain training’ apps, Which? told consumers not to waste their money on such products but seek free medical advice.
Alex Neill, Which? director of policy and campaigns, lambasted companies “preying on people’s fears”.
5 dementia products you don't need
Which? focused on five products available online and on the UK high street – Bioglan Calamari Gold capsules, Efamol Brain Active Memory capsules, Boots Sharp Mind tablets, BrainSmart Memory capsules and Dementia Test app – in a release entitled ‘Five dementia products you don't need’.
The report has already resulted in the withdrawal of some marketing material.
“Efamol told us it didn’t intend to mislead consumers, takes the matters we’ve raised seriously and apologises unreservedly. It has taken down its website temporarily while undertaking a rigorous review,” Which? said.
The company claimed its vitamin B12 and folic acid Brain Active Memory product contributes to normal brain function and protects against vascular and brain cell damage including stroke which can cause dementia.
But the watchdog said some of the claims for the product – which costs £10.99 (€13.91) for 30 capsules – were not substantiated by the European Food Safety Authority (EFSA) and were “potentially misleading”.
NHS England research shows that more than 750,000 people in the UK suffer from some form of dementia, the most common being Alzheimer’s.
In Europe is was estimated 7.3 million Europeans in 27 member states between 30 and 99 years of age suffered from different types of dementias in 2006. That’s about 15 people in every 1,000.
Within this group, significantly more women than men were affected, at 4.9 million and 2.4 million, respectively.
“The brain does need B6 and B12 for normal brain function, and you should get these from your diet anyway,” said Which?.
Meanwhile the watchdog said it would report BrainSmart’s “potentially misleading” claims that its Gingko biloba, B vitamins and N-Acetylcysteine product could improve memory and prevent dementia and Alzheimer's Disease to the UK’s Advertising Standards Authority (ASA).
The company said its product – £24.89 (€31.52) for 60 capsules – was in line with regulation, but added that EFSA was “behind the curve”.
Which? also criticised Bioglan (Pharmacare Europe) for boasting of the added benefits of its higher 400 mg DHA levels.
“However, there are cheaper fish oil supplements containing higher levels of DHA available if you want them, and just 250 mg of DHA per day would be enough for meeting claims of maintaining normal brain function anyway,” it wrote on the product costing £24.99 (€31.62) for 30 capsules.
‘Entirely permissible, and without misleading consumers’
Yet the Health Food Manufacturers’ Association (HFMA) said Which? had failed to consider the “huge body of positive evidence” suggesting a link between omega-3s and cognitive function in particular.
In a statement, the trade group said a distinction had not been made between products and their specific, regulated ingredients and the report had “confused” claims that can be legally made and those that cannot.
“It is well-known and very clear that claims such as ‘prevent dementia’ are illegal. Equally, it is the case that the EU regulators have fully authorised a number of claims in regard to brain function for a range of particular nutrients such as iron, zinc, vitamins B12 and B6.
“It is entirely permissible, and without misleading consumers, for products to include ingredients authorised in relation to brain claims alongside other ingredients that deliver other benefits.”
What the Alzheimer’s Society thinks
Dr Ian Le Guillou, research officer at the Alzheimer’s Society, said more research was needed on the role diet and nutrition plays in reducing the risk of dementia.
“Research has shown that the best ways to reduce your risk of dementia is a healthy diet, physical activity and not smoking.
“We still do not know exactly which aspects of diet are important, but studies of supplements for vitamins and omega-3 have not been conclusive. The relationship between nutrition and brain health is complex.”
He urged those worried about memory to seek medical advice.
“Dementia is the most feared condition in the UK and it is important that health claims for supplements are backed by evidence,” he added.