J Nutrition August, 2010 -See this, longer synopses, and links to published articles below or at Nutrition investigator .

SUMMARY - No easy answers. Even caloric restriction and green tea, both heralded for extending life and healthspan, have negative aspects, dampening your immune system. But there's lots of benefit from good nutrition. Phytochemicals from green tea, broccoli, etc. reduce your lung cancer risk. Vitamin E decreases fat deposition. Leucine (from branched chain amino acid supplements) stimulates skeletal muscle growth. Vitamin A regulates immunity. A high fiber diet reduces heart disease risk . CLAs (in milk fat) reduce inflammation from arthritis. And folate helps to reduce hearing loss. The only hazard noted in this issue of the Journal of Nutrtion is that a high fat diet harms your heart function.

If you are in the northern hemisphere, I hope you are eating lots of vegetables from a bountiful garden.
Sincerely, Roc - Nutrition Investigator