This is the very basics of food requirements, for new piggie owners. Additional discussions regarding food and other health topics will be found at Cavyinfo International.

Always buy the best food for your piggie! My piggies eat better than I do! Food and nutrition play a big role in health; the better the nutrition, the better the chances for good health and a long life.

We are finding out how important guinea pig nutrition is. A guinea pig's life expectancy is six to eight years - up 50% from the four to six years everyone "accepted" in the eighties. We hope that as veterinary medical trends and nutrition continue to improve, lifespans will be even longer.

A high-quality guinea pig food pellet should always be used. Many food pellets contain animal by-products that have been preserved with a compound called ethoxyquin. This preservative (which is also used as a rubber stabilizer) is a topic of debate, with claims ranging from causing to preventing cancer. That’s too big a point spread for me. Until they prove it safe, I try to avoid it from going in my piggies’ mouths. You can read more about ethoxyquin and draw your own conclusions from these articles.

Other food "additives" such as seeds and "crunchies" do nothing except offer added calories - something a basically chubby animal does not need! Treats, such as seeds, etc. should be just that: something that is fed on an occasional and controlled basis, not as a staple. For example, Oxbow Hay Company offers a full-range of excellent food that does not rely on animal by-products or chemical preservatives.

In addition to the pelleted food, a variety of fresh vegetables and fruits can be offered: apples, carrots, melon and sweet bell peppers are all favorites. Lettuce is also enjoyed by piggies, but "varieties" such as Romaine or Red and Green Leaf lettuce should be used, not iceberg which is nutritionally useless. Greens should be fed sparingly, as they can cause diarrhea.
High quality hay should also be offered free-choice: younger piggies (and piggie-mothers-to-be) benefit from alfalfa hay, but as the piggie matures (after 10 months to a year), it is better to switch to timothy hay, as it is less fattening, and contains less calcium than alfalfa, which could cause problems in later life (it is suspected that excess calcium may cause bladderstones in some piggies). Both Oxbow and American Pet Diner offer excellent hay.
Make sure your piggie has a water bottle that suits his drinking habits (piggies will drink from 2 to 16 ounces a day, depending on the piggie. The average is about 6 - 8 ounces). Change the water daily, and be sure the sipper tube is working: piggies love to play "backwash" and spit chewed goop into the sipper tube!