Which area of a casino makes the most money? You might think it’s the big money tickets, the blackjack – or perhaps the roulette table?

It’s actually the slot machines – because they don’t cost much, are even cheaper to maintain and are so addictive people just keep playing, even when they’ve lost a small fortune.

When Dr Nick Tiller was investigating the marketing tricks and claims behind the booming health and wellness industry for his new book, he kept thinking of those casino slot machines.

Because the more he uncovered, he says the more apparent it became that the slot machines of the wellness industry are vitamins and dietary supplements.

Cheap to make, these supplements also have huge profit margins and are growing ever more popular by the year.