The agency was appointed to the business, which is estimated to be worth around £60 million in spend, following a pitch involving a number of Unilever roster shops.
DDB London was the incumbent on the account and had worked on the business since November 2009, after winning a pitch against the previous incumbent, Bartle Bogle Hegarty.
In the UK, Becel is known as Flora, the account for which is still handled by DDB London and is unaffected by Lowe's appointment to the global business.
Lowe will now be responsible for revamping Becel's positioning internationally by highlighting the claimed long-term health benefits that the product provides to those who consume it.
The account will be run out of the agency's London and Madrid offices, and particular emphasis will be placed on creating greater awareness of Becel in northern Europe and Latin and North America.
Unilever is one of Lowe Worldwide's biggest clients, with the agency overseeing work on brands including Magnum and Knorr.
In the UK, Flora recently launched a TV campaign to promote its Cuisine cooking oil. The ad, created by DDB London, starred the TV presenter Vernon Kay and his mother, Gladys.