I think that the secret to achieving a healthy body is by eating healthy diet meals, exercise and avoiding preservatives, MSG, and vices such as smoking and drinking beer.
When it comes to diet, you must give your body nutrients to keep your systems going. Don't eat too much cholesterol because it can cling to your artery walls, cause clogging and resulting to high blood pressure. Do exercise to remove waste from your body in the form of sweat. It also improves your blood circulation and increases your rate of metabolism. Stopping your smoking vices could do your lungs a favor by giving it fresh air.
However, social factors could affect your motivation in engaging in a healthier lifestyle. When friends invite you to parties, you eat high cholesterol food and too much sugar. Other cases may call for a celebration so you drink beer. These cases are inevitable but just take it into moderation. After the party, release all the waste you've build up by detoxifying and exercising.