Sensa is one of several products said to reduce appetite - and thus the amount you eat - through the use of appetizing aromas to fool you into feeling full. The Sensa approach involves buying sugar-free, calorie-free food flakes that you sprinkle on your food. The flakes come in a number of flavors ranging from cheddar and parmesan cheese, onion, and taco, as well as sweet flavors including cocoa, spearmint, banana, strawberry and raspberry.
Sensa's developer, Alan Hirsch, M.D., founder of the Smell and Taste Treatment and Research Foundation in Chicago, has presented results of a study showing that of more than 1,400 overweight men who participated, those who stayed with the program for six months lost an average of just over 30 pounds by sprinkling the flavored flakes on their food. The study has not been published in a peer-reviewed journal. And I've seen no follow-up on the study participants to show whether or not they succeeded in keeping their weight off.
Despite the lack of evidence that scent can promote weight loss, the idea is apparently catching on. You can now get a nasal spray to be used before meals to tamp down your appetite with scents. Another scent-related weight loss product is the Aroma Patch, a new twist on aromatherapy. You wear the patch on your skin and the scent it gives off is supposed to remind you to stick with your diet and exercise program.
Dr. Hirsch has explained that his decision to explore this approach to weight loss was rooted in the knowledge that people who lose their sense of smell and taste due to head injuries often gain weight rapidly. Since that is true, could the opposite be true - could heightening the scent and flavor of food make you feel full faster and eat less? As of now, in my view we have no good evidence for that possibility.
These products may not cause any harm, but there are no short-cuts to weight loss. Shedding extra pounds takes effort and planning. You have to cut back on what you eat - focus on the right amount of the right kind of food - and try to burn calories through stepped up physical activity.
To lose weight while maintaining or improving your health, I recommend my anti-inflammatory diet coupled with mindful eating, calorie-consciousness and daily physical activity.
Andrew Weil, M.D.