Linseed is the small, reddish-brown or golden-yellow seed of the common flax plant, linum usitatissimum, exactly the same plant as is used to grow the fibre from which true linen has been made for thousands of years. Some flax plants – not a different variety – produce more seeds than others and these have carefully been chosen as a crop plant. It’s equally correct to call the same small seeds linseed or flaxseed.
More traditionally pressed to make linseed oil, without which heritage paints and cricket bats would not be the same, the seeds have long been used medicinally to help with constipation but also come packed with many components that have health benefits. They are more likely to be recommended as a vegetarian source of an important single Omega-3 fatty acid, usually found in fish oils, but the accessibility of this ingredient can be affected by association with other constituents and it’s best to take specialist dietary advice if this is important.