According to a report in the Independent on Sunday, Unilever will be launching new products, including soup and snacks, and will run a marketing campaign saying that it is safer than losing weight through a low-carbohydrate diet.
The newspaper reports that Unilever co-chairman Antony Burgmans is to visit Slimfast's Florida headquarters to look at developing a fightback plan. It also says that the brand may consider looking for celebrity endorsements.
Slimfast helps people to lose weight by replacing meals with low-calorie shakes, but it has expanded its range to include pasta, snack bars and soups.
In May, Unilever blamed a drop in sales of Slimfast on the increasing popularity of Dr Atkins' diet, which advocates high protein and no sugar, and allows adherents to eat the foods usually banned from weight-loss regimes such as cheese, eggs and bacon.
Unilever followed by launching a new advertising campaign by Grey London, taking a more humorous approach and telling people to "stop dieting, start losing weight".
The Atkins plan is growing in popularity and according to new research three million people in the UK are following the controversial diet.
This is despite fears about its safety. The diet has been criticised by health professionals because it does not restrict the intake of fat and there have been claims that people have died as a result of the diet.
The British Nutrition Foundation says that people using it risk kidney health and heart disease." However, a US study showed that the Atkins Diet could protect against heart problems.
While Dr Atkins' diet is a bit hit in UK bookshops, the programme is failing to make inroads into mainstream retailing. Last week, it was revealed that Atkins Nutritional, the company behind the successful diet regime, faced difficulties finding distributors for a range of Atkins-branded food because UK retailers were reluctant to back the controversial diet.
Unilever bought Slimfast in 2000 for $2.3bn (£1.46bn), and has been looking at ways of giving it a broader appeal to health-conscious consumers, instead of just those who are trying to lose weight within a specific period.
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