Contents. 1  Inflammatory joint effusion AND Stiff hip: Causes of All Symptoms. 2  Inflammatory joint effusion OR Stiff hip: Causes of Any Symptom. 3  Inflammatory joint effusion: Causes. 4  Inflammatory joint effusion: Introduction. 5  Stiff hip: Causes. 6  Stiff hip: Introduction.
Sardines are an important part of the food chain. Jupiterimages/Photos.com/Getty Images. Sardines live in large schools that may contain thousands of fish. They typically feed on plankton and are close to the bottom of the food chain; many different kinds of predators eat sardines, including humans.
Sardines are also a good source of omega-3 fats, and they are low in saturated fat. They contain as much calcium as a glass of milk, the B vitamin niacin, protein and iron. They are a convenient fish choice, since you can buy them fresh or canned and packed in oil. Sardines are also low in mercury.