Health experts give people all sorts of advice for losing weight. Most weight-loss studies last a maximum of only 6 to 12 months and can’t tell us much about what works over 5, 10, or 15 years. A remarkable study from Harvard University examined more than 120,000 people in three, four-year increments beginning in 1986.
People gained more than 3 pounds during each four-year period. Factors linked to the weight gain included potato chips (1.7 pounds), French fries (1.3 pounds), high-sugar drinks (1 pound), red meat (1 pound, and processed meats (0.9 pounds). Foods that triggered long-term weight loss included vegetables (-0.2 pounds), whole grains (-0.4 pounds), fruits (-0.5 pounds), nuts (-0.6 pounds), and yogurt (-0.8 pounds). Increasing physical activity caused an average four-year weight loss of 1.8 pounds, while watching television increased weight by 0.3 pounds per hour per day.
Based on this study, the best advice to assist you in long-term weight control is to increase your intake of yogurt, nuts, vegetables, and whole grains, exercise more, and decrease your consumption of potato chips, sweetened drinks, and red meat.
New England Journal of Medicine, 364: 2392 – 2404, 2011