December 19, 2013
News Review From Harvard Medical School -- 2-Year, 10% Weight Loss May Boost Health
Women in a study who kept off excess weight for 2 years may have reduced their risk of heart disease and diabetes, researchers report. The study included 417 overweight or obese women. They were randomly assigned to follow either the Jenny Craig program or a self-directed diet program. They provided fasting blood samples before the study. Researchers checked blood samples again after 12 and 24 months. About 70% of all women had sustained weight loss after 2 years. Those who followed the commercial program had greater reductions. Women who lost at least 10% of their weight and kept it off for 2 years also showed signs of better health. They had improvements in factors that affect the risk of heart disease and diabetes. These included lower LDL ("bad cholesterol") and triglycerides, another blood fat. They also had a drop in C-reactive protein, which indicates inflammation. They had lower levels of blood sugar and insulin, showing that their bodies were making better use of insulin. This means they were less likely to develop diabetes. The Journal of the American Heart Association published the study online. MedPage Today wrote about it December 19.
By Robert H. Shmerling, M.D.
Harvard Medical School
What Is the Doctor's Reaction?
Are you tired of hearing about how important it is to maintain a healthy weight?
If you are, it's understandable. The message seems to be everywhere: public service announcements, newscasts, newspapers, health club advertisements. Soon we'll be hearing about New Year’s resolutions to eat well, exercise more and lose excess weight. And we'll hear about how often those plans fail.
But it's true: Study after study has concluded that losing excess weight is good for you. And excess weight, lack of exercise and poor food choices play a major role in several serious ailments. These include diabetes and heart disease.
Just how much weight loss is enough, however, remains uncertain. A few pounds above the ideal are probably not terrible for you. But obesity is a major risk factor for poor health.
The latest news on this subject comes from the Journal of the American Heart Association. The study included more than 400 women who had been in weight-loss programs for up to 2 years. Researchers found that the women who lost 10% or more of their body weight and kept it off greatly improved factors that increase the risk of heart and blood vessel disease. The changes included:
- Reductions in LDL ("bad cholesterol") and triglycerides
- Improved blood sugar and insulin levels (indicating less risk of diabetes)
- Reduced levels of inflammation
And those who benefited the most from the weight loss were those who had the highest risk at the start of the study.
While that's encouraging news, it's not easy to lose the amount of weight these women lost. If you are obese and weigh 200 pounds, it means losing 20 pounds. This study enrolled women who already were motivated. Yet only 29% managed to lose 10% of their body weight.
Keeping that much weight off may be even harder than losing it in the first place. In this latest study, a full quarter of study subjects had no weight loss at all at the two-year mark.
But this study shows how profound the health benefits can be if you are able to lose significant weight and keep it off.
What Changes Can I Make Now?
Calculate your body mass index (BMI) to find out whether your weight is "normal" or too high. For most people, the BMI should be between 19 and 25.
If you are overweight or obese, adopt the habits of people who have been successful at losing excess weight and keeping it off. For example:
- Find activities you enjoy and make exercise a part of your everyday routine.
- Increase the number of calories you burn each day even when you aren't actually working out. For example, take the stairs or choose the parking spot at the far end of the lot.
- Talk to your doctor about your medical problems and how they may limit your ability to exercise. Consider meeting with a physical therapist or personal trainer to create an exercise program that's safe for you.
- Review the types of foods you eat and how they may be contributing to excess weight. Make it a habit to read food labels. Consider meeting with a nutritionist.
- Compare the portions you tend to eat with the nutrition label's description of a single serving size. For many people, losing excess weight is more about reducing portion size than changing the specific foods they eat or exercising more.
- Avoid temptation. Don't bring junk food or high-calorie beverages to work or into your home. Avoid buffets, as they tend to encourage overeating.
The next time you hear about the virtues of losing excess weight, don't ignore it! Think about your routine activities and what you eat. Even small changes can make a big difference.
What Can I Expect Looking to the Future?
Given the epidemic of obesity in the United States, you're likely to hear more about how to avoid becoming overweight or obese and how to lose excess weight. You can also expect to hear new claims about the best ways to lose weight. But I think we are recognizing that that there is no single best option. Jenny Craig sponsored this study. But it's likely that other weight loss programs, such as Weight Watchers or Nutrisystem, could have been just as successful.
If you're trying to lose excess weight, the goal shouldn't be to find the best way. There is no such thing. The goal should be to find a safe weight-loss program that works for you.