Shoppers may be wasting money buying omega-3 supplements labelled as 'high-strength', an investigation reveals. Similarly, Holland & Barrett's High Strength Omega 3 Fish Oil 1500mg contained just 375mg, well below the 450mg daily advised dose. Holland & Barrett's 1500mg 'high strength' supplement costs 27p per daily dose despite providing just 375mg of EPA and DHA. A Holland & Barrett spokeswoman said: 'There is currently no legal or industry-wide definition of what constitutes a 'high strength' omega-3 fish oil supplement. 'At Holland & Barrett, the term is used to help customers distinguish between the different strengths and formulations of omega-3 products within our range.