They sleep well
According to research, those who sleep 8 hours a day or more are three times less likely to develop a cold, compared to people who sleep for less than 7 hours. The reason; Lack of sleep causes more stress, as more cortisol (known as the "stress hormone") is produced, which raises blood pressure, even increasing the chances of heart attacks and strokes.
Researchers from Columbia University have also shown that adults who sleep a few hours a day are more likely to become obese!
They follow a balanced diet plan
Fill your diet with foods rich in antioxidants such as sweet potatoes (beta-carotene), citrus fruits, peppers (vitamin C), almonds (vitamin E), red grapes and red wine (resveratrol), with this way you will replenish damaged cells to fight germs and bacteria. Probiotics such as yogurt also build defenses.
They are active
Studies show that regular and moderate exercise can reduce the number of colds and flu symptoms by at least 25-50% over the course of a year, most likely by boosting the circulation of cells that fight infections. Remember that exercise is better than any advertised treatment!
They wash their hands often
Regular hand washing dramatically reduces diseases of the respiratory and gastrointestinal tract. Be sure to wash their hands frequently (or use a hand sanitizer) after using Public Transport, after work, and before and after each meal.
They are social
Research from Buffalo University in New York has shown that those who have many friends are at lower risk of developing respiratory infections, as well as heart problems, depression and anxiety. Harvard research has also shown that people with a large social circle are less likely to have memory problems.