I spend entirely too much time researching this stuff, but I prefer not to rewrite things where I have nothing to add. When I come across awesome stuff I’ll add it here:—
A great starting point, complete with everything from research backed suggestions to meal plans and guided lessons for people of all ages.
2008 Physical Activity Guidelines for Americans
“The first comprehensive guidelines on physical activity ever to be issued by the Federal government.” These highlight the risks, benefits, and current understanding of the interplay between physical activity and health.
Healthy Recipes by The Mayo Clinic
Complete recipes with nutritional information for following their weight loss plan, more details available in the Mayo Clinic Diet Book.
NIHLB Guidelines on Weight loss
Some great, and really comprehensive information about the risks of sedentary lifestyles and finding healthy ways to maintain body weight.
Great infographic series from Precision Nutrition about where to start.
US News has a treasure trove of expert commentary on popular diets
Maintained by the University of Sydney, this database contains up-to-date information on glycemic index information. Since GI is measured directly, not calculated, it is surprisingly hard to track down good numbers for this stuff.
Tons of great data on all sorts of health policy stuff, and is a great place to ‘check the numbers’ on health Claims
Great site when you want to check the math on something ridiculous such as how many calories the moon would have if it was made of cheese (2.1 x 10^26 Cal btw)
USDA Nutrition Database Search
The United States Department of Agriculture has a search function for it’s database, although you are probably better off using the cleaned up data in our food browser