LONDON — Help may soon be on the way for chocoholics.
Dieticians at St. George's Hospital in London said Monday they have tested a skin patch that releases whiffs of vanilla and other scents that help reduce cravings for chocolates and other high-calorie sweet snacks.
People who wore the patch on the back of their hand in early tests experienced a change in appetite and lost an average of 4.5 pounds.
"It halved their intake of chocolate," said Catherine Collins, the hospital's chief dietician who led the study.
"Sugary drinks were also significantly reduced," she added in a telephone interview.
The dieticians randomly divided 200 overweight volunteers into three groups that received either a vanilla patch, a lemon or dummy patch or no patch.
After four weeks the weight loss in the control groups — the lemon and no-patch groups — was only a fraction of the loss by people who wore the vanilla patches.
Collins, who will present her findings on Wednesday at the 13th International Congress of Dietetics in Edinburgh, Scotland, says she is unsure how the vanilla patch works but she thinks it may influence satiety.
The research will also be submitted to a medical journal.
"We know that taste and aroma do have a feedback on brain biochemistry fairly immediately to tell you to stop eating. In psychology literature there has been a lot of work on this, but it has never been applied to obese patients before," she said.
Although the patch reduced the urge for chocolate and sweets, it had no impact on fatty or starchy food or alcohol.
"There is some research that shows very sweet smells release serotonin in the brain. Serotonin is a mood chemical that makes you feel good, which is why chocolate also has that effect. Its chemical content produces serotonin," she said.
The vanilla is released from the patch and not absorbed through the skin. Although a few people said the smell made them feel a bit nauseous, Collins said the patches do not cause any serious side effects.
The patches will be available in Britain in September from The Aromacology Patch Co. Ltd.
Liz Paul, who invented them, said although the patch smells of vanilla it is actually a patented concoction of smells.
"It smells of vanilla but actually it is much more scientific. It is a cocktail of perfumes," she said.
It is the first of five patches the company will produce. The second is designed to reduced cravings for fatty snacks such as fries or potato chips and others will deal with insomnia and pre-menstrual stress or PMS.