for respiratory

•Stop smoking and stay away from secondhand smoke.

•Avoid indoor and outdoor air pollution.

•Avoid exposure to people who have the flu or other viral infections.

•Exercise regularly.

•Eat a healthy, balanced diet.

•Maintain a healthy weight.

for digestive system

•Eat a high-fiber diet. ...

•Be sure you're getting both soluble and insoluble fiber. ...

•Minimize your intake of foods high in fat. ...

•Select lean meats. ...

•Add probiotics to your diet. ...

•Follow a regular eating schedule. ...

•Drink plenty of water.

for circulatory system

•Eat a heart healthy diet. ...

•If overweight, lose weight. ...

•Increase regular physical activity to at least 2.5 hours per week. ...

•Don't use tobacco. ...

•Avoid use of alcohol. ...

Have your blood pressure and blood sugar checked regularly.