These five areas were chosen because prior studies have shown them to have a large impact on risk of premature death. Here is how these healthy habits were defined and measured:
1. Healthy diet, which was calculated and rated based on the reported intake of healthy foods like vegetables, fruits, nuts, whole grains, healthy fats, and omega-3 fatty acids, and unhealthy foods like red and processed meats, sugar-sweetened beverages, trans fat, and sodium.
2. Healthy physical activity level, which was measured as at least 30 minutes per day of moderate to vigorous activity daily.
3. Healthy body weight, defined as a normal body mass index (BMI), which is between 18.5 and 24.9.
4. Smoking, well, there is no healthy amount of smoking. "Healthy" here meant never having smoked.
5. Moderate alcohol intake, which was measured as between 5 and 15 grams per day for women, and 5 to 30 grams per day for men. Generally, one drink contains about 14 grams of pure alcohol. That’s 12 ounces of regular beer, 5 ounces of wine, or 1.5 ounces of distilled spirits.