Thin may be in, but is it healthy?
Individuals who are overweight and in poor health can certainly benefit from losing weight, but those who are overweight and otherwise healthy often do not benefit from weight loss. In fact, overweight individuals may even be better off maintaining their excess pounds than losing weight. A review of the research reveals why everyone should focus on health and fitness, forget about fatness, and learn to love their bodies.
As we age, some weight gain can be protective against certain diseases. Heavier women tend to have stronger bones and experience less bone loss after menopause. Before menopause, heavier women are less likely to develop breast cancer. A Harvard study published in the Journal of the American Medical Association followed more than 1,000 women for 8 years. Researchers found that the risk of breast cancer decreased as weight increased among premenopausal women.
Modest weight gain may even extend our lives. A study published in the Annals of Internal Medicine found that the weights associated with the lowest death rates increased with age. As adults got older, weight gain reduced their risk of death. Other studies have come to the same conclusion, including a large review of 13 trials at the National Institutes of Health. Again, researchers found that the lowest mortality rates were associated with modest weight gain.
Where weight is gained can be an important factor. Excess fat tissue around the buttocks, hips and thighs is associated with strong bones and, according to researchers at Stanford University School of Medicine, a lower risk of cardiovascular disease. However, weight gained around the waist has the opposite effect. Studies link excess abdominal fat to an increased risk of metabolic syndrome, type 2 diabetes, depression, cardiovascular disease including hypertension and stroke, gallbladder disease, cancer and death.
Losing weight has been linked to an increased risk of death and disease too. A study at the Centers for Disease Control and Prevention found that for women with obesity-related health problems, weight loss lowered their risk of death by 20 percent, primarily due to a 40 to 50 percent reduction in the number of cancer deaths. Women who lost weight intentionally also reduced their risk of diabetes-related death by 30 to 40 percent. However, overweight women with no pre-existing illnesses who lost moderate amounts of weight (up to 19 pounds over the course of one year) had an increased chance of dying from cardiovascular disease, cancer, and all causes.
According to another study by the CDC, overweight adults with a body mass index of 26 to 29 who lost 15 percent or more of their maximum body weight died more than twice as often as those who lost less than 5 percent. Researchers studied more than 4,600 men and women for up to 16 years, adjusted for age, race, smoking, preexisting illnesses and maximum body mass index, and concluded that for overweight (but not obese) individuals, the risk of death increased with increasing weight loss.
In Finland researchers followed more than 40,000 people for 12 years and found that thinness was associated with a greater risk of death in both men and women. Compared to their heavier counterparts, thin women under the age of 65 and thin men of all ages had higher mortality rates. Among women 65 years and older, mortality had little association with weight and thin women died more often from cancer than from other causes.
The National Heart, Lung and Blood Institute looked at weight loss over an even longer time span: three decades. Researchers found that weight loss over 30 years was associated with a higher risk of cardiovascular disease and death, while maintaining a stable weight over 30 years was associated with a lower risk.
The majority of people who lose weight gain it back eventually. The disappointing truth is that even the most dedicated individuals are largely unsuccessful at significant and permanent weight loss. Studies show that after two to four years of regular exercise and a healthy diet, the average weight loss is less than 5 kilograms or 11 pounds.
Weight loss followed by weight gain, also called weight-cycling, can be hard on the cardiovascular system. Swedish researchers that analyzed 32 years of data from the famous Framingham Heart Study found that fluctuations in weight increased the risk of developing and dying from coronary artery disease. Once weight was gained, it was better to maintain that weight than to lose the extra pounds.
Physical and Metabolic Fitness
Fortunately, you don’t have to lose a lot of weight to benefit from exercising and eating well. People who are overweight and exercise regularly are more likely to be healthy than their thin but sedentary counterparts. A study published in the Journal of the American Medical Association followed more than 13,000 men and women for over 8 years. Researchers found that the highest levels of physical fitness were associated with the lowest risk of death from cardiovascular disease, cancer, and all causes.
Another study, published in the New England Journal of Medicine, followed almost 17,000 adults for up to 16 years. Again, researchers found that the risk of death was lowest among physically active people, regardless of weight. They estimated that by age 80, regular exercise can add an extra one to two years to your life.
Being physically active and eating a diet low in simple carbohydrates (like sugar and flour) also promotes metabolic fitness, the optimal function of vital internal processes. Metabolic fitness can be evaluated by measuring blood pressure and levels of glucose, insulin, and triglycerides in the blood (among other factors). Individuals who are metabolically fit have a low risk of chronic illnesses like type two diabetes, cardiovascular disease and cancer.
Because a healthy diet and regular exercise promote physical and metabolic fitness, these lifestyle changes alone can prevent and even reverse disease whether you lose weight or not. A study published in the American Journal of Cardiology followed 72 adults through an intense three-week diet and exercise program. Some participants were type two diabetics, others were insulin resistant, and the rest had normal insulin levels.
At the end of the program, after only three weeks, every single person experienced lower blood pressure, reduced levels of insulin and triglycerides in their blood, and a reduction in body mass index. Results were most dramatic in those with type 2 diabetes, but everyone benefited and more than half the individuals who were insulin resistant reversed their condition within three weeks. Weight loss wasn’t great. Most people who were overweight and obese at the start of the study were still overweight and obese at the end of the study, but the researchers concluded that weight loss wasn’t necessary to reduce metabolic risk factors.
The Bottom Line
Losing weight is often a losing battle because our bodies are programmed to prevent weight loss. It’s a survival mechanism controlled by complex systems of hormones and neurological feedback that we have yet to fully unravel.
If you’re overweight, focus on fitness instead of fatness. Ask your doctor to give you individualized recommendations and track your success by measuring blood pressure, waist circumference, and levels of metabolic markers like:
- Hemoglobin A1C
- LDL particle size
- Apolipoprotein B
- C-reactive protein
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