'Always follow your gut instinct'

British company Grenade started off making specialist protein products for athletes.

However, founder Alan Barratt had a gut feeling that many people would prefer to eat his protein bars rather than sugary chocolate bars. His board was sceptical, but he forged ahead.

Now, his Carb Killa bars are one of the most popular snack bars in the UK.

Video journalist: Jeremy Howell

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