Some studies have suggested that diet soda lovers could face higher risks of diabetes and heart disease, but one recent US study of several diet drink consumers found that overall eating habits may be what matters most in the end. Researchers, whose findings were published in the American Journal of Clinical Nutrition, used data on more than 4,000 people taking part in a long-term study of heart health and followed them for the next 20 years. Of the study participants between the ages of 18 and 30 when it began in the mid-1980s, 827 subsequently developed metabolic syndrome — a cluster of risk factors for heart problems and diabetes including extra weight around the waist, unhealthy cholesterol levels, high blood pressure and elevated blood sugar.