If recent studies are any indication, companies looking to cash in on the low-carb craze had better move quickly. Already, supermarket shelves are awash with items reformulated to trim the dreaded carbohydrate, but recent statistics suggest consumer interest in the craze may be abating.

According to The NPD Group (Port Washington, N.Y.), the percentage of Americans following low-carb diets like Atkins and South Beach dropped to 4.6% in September. This is from the 9% mark reported in January. Furthermore, sales of those diet-related books have tapered off, as well, with only about 20,000 copies selling per week, down from the 70,000-a-week tally at the peak of the craze.

In addition, ACNielsen (New York) reports slower sales of products targeting the carb-cutting consumer. Dollar sales of the items rose 6.1% during the 13 weeks ending September 25, a drop from the double- and triple-digit gains in prior periods.