I am looking for the size and growth of the U.S. "functional" food
industry. Also, what the trends in the "functional" food industry are.

Hi! Thanks for the question.

Here are the estimated market sizes of functional foods for the United
States for different years. With these you can get an estimate of the
growth of this industry.

1999 ? $16 Billion
2000 ? $17.3 billion
2002 - $20.2 billion
2003 - $18.5 billion
2004 - $19 Billion
2005 - $29.39 billion

Forecasts:
2006 - $35.86 Billion
2009 - $59.87 Billion


Sources for Figures:

?Functional Foods and Nutraceuticals? (1999-200 data)
http://www.agr.gc.ca/misb/fb-ba/nutra/index_e.php?s1=bmi&page=annexc 

?Functional foods establish place in food industry? (2002 data)
http://www.nutraingredients-usa.com/news/ng.asp?id=25586-functional-foods-establish

?New directions in food marketing? (2003 data)
http://www.ferret.com.au/articles/85/0c03e785.asp 

?Symrise enters functional foods market? (2004 data)
http://www.nutraingredients.com/news/ng.asp?id=65186-symrise-kaden-functional-foods

?Top Ten Functional Food Trends? (2005 data Plus 2006 and 2009 Forecast))
http://members.ift.org/NR/rdonlyres/504BC1ED-53DC-4A67-88A7-EC560ACF28BE/0/0406topten.pdf


---------------------------
According to the Institute of Food Technologists (IFT), the top trends
for functional foods will be the following:

1. More concern and development of food products geared for the health of children.

2. 100-Calorie Cut Off in Food Products

3. Phytochemicals will move into mainstream products.

4. Food products with multi-health benefits.

5. The emergence of healthy fats and oils. Even though these are more
expensive, consumers are buying more healthy oils.

6. Marketing of functional foods will be catered more to those over the age of 50.

7. Products which are low in glycemic, gluten free and are whole grain
will have a significant impact on the market.

8. The organic food market will also show growth.

9. Energy foods and drinks will continue to grow.

10. Low-fat sugar-free candies, ice-cream will continue to move
mainstream and more products will continue to move into the market as
buyers become more health conscious.

?Top Ten Functional Food Trends?
http://members.ift.org/NR/rdonlyres/504BC1ED-53DC-4A67-88A7-EC560ACF28BE/0/0406topten.pdf


AC Nielsen also provides other sets of trends in this article. The
analysis is almost the same as the IFT document.

?GI, antioxidants to lead 2006 health trends, says AC Nielsen?
http://www.nutraingredients-usa.com/news/ng.asp?id=65499


Search terms used:  
"Functional Foods" 2006 market trends

I hope these links would help you in your research. Before rating this
answer, please ask for a clarification if you have a question or if
you would need further information.
                                                          
                              
Regards,                              
Easterangel-ga                              
Google Answers Researcher