To tie in with millions of Americans' New Year resolutions, bestselling author Dr Steven Pratt has expanded the definition of functional foods in his book "SuperFoods HealthStyle". Additions to the list of nutrient-rich 'superfoods' include: apples, cinnamon, kiwifruit, herbs and spices, honey, dark chocolate and pomegranates.

As an alternative to fad diets, functional foods are likely to have a lasting effect on an individual's weight and long-term health, the author suggests.

According to the National Centre for Health Statistics, 30% of American adults 20 years of age and older - more than 60 million people - are obese while the latest National Health and Nutrition Examination Survey (NHANES) has found that 65% of American adults are overweight.

One organisation to make a prompt response to help curb the country's widening waistlines is Wild Oats Market, a leading national natural and organic foods retailer. It is expanding its storewide superfoods education programme to help consumers boost overall health, and achieve and maintain a healthy weight, naturally, in the New Year.

In addition to encouraging customers to incorporate more nutrient-dense superfoods into their diets, Wild Oats has created the Superfoods - Super You! Healthy Eating Plan.

One of the advantages of this plan is that it takes a holistic approach to the problem of obesity and health, says Tricia DiPersio, PhD, RD, Food Safety Specialist and Corporate Dietician for Wild Oats Markets.

"Instead of telling people what they should avoid, as most diets do, our programme focuses on the foods people should be eating to support a healthy lifestyle, or superfoods."