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Healthy Weight

Maintain, Don’t Gain

  • Maintaining a healthy weight is important for health. In addition to lowering the risk of heart disease, stroke, diabetes, and high blood pressure, it can also lower the risk of many different cancers.
  • Move more, eat less. Turning off the television and skipping the sugary drinks are two ways to get started.

Your weight, your waist size, and the amount of weight gained since your mid-20s can have serious health implications. These factors can strongly influence your chances of developing the following diseases and conditions:

  • Cardiovascular disease, heart attack, stroke
  • Diabetes
  • Cancer
  • Arthritis
  • Gallstones
  • Asthma
  • Cataracts
  • Infertility
  • Snoring
  • Sleep apnea

If your weight is in the healthy range and isn’t more than 10 pounds over what you weighed when you turned 21, focus on maintaining that weight by watching what you eat and exercising.

Because most adults between the ages of 18 and 49 gain 1-2 pounds each year (1), stopping and preventing weight gain should be a priority. Gaining weight as you age increases the chances of developing one or more chronic diseases.

  • In the Nurses’ Health Study and the Health Professionals Follow-up Study, middle-aged women and men who gained 11 to 22 pounds after age 20 were up to three times more likely to develop heart disease, high blood pressure, type 2 diabetes, and gallstones than those who gained five pounds or fewer.
  • Those who gained more than 22 pounds had an even larger risk of developing these diseases. (2-6)
  • Another analysis of Nurses’ Health Study data found that adult weight gain—even after menopause—can increase the risk of postmenopausal breast cancer. (7)
  • Encouragingly, for women who had never used hormone replacement therapy, losing weight after menopause—and keeping it off—cut their risk of post-menopausal breast cancer in half.

Does Being Overweight Reduce Mortality?

You may have seen news coverage of a study claiming that being overweight and obese may reduce mortality (8, 9) but a panel of experts discussed why the general public should not rely on these flawed study findings.

  • The main flaw of this study is that the normal weight group, which showed an increased mortality risk compared to the overweight group, included more heavy smokers, patients with cancer or other diseases that cause weight loss, and elderly people suffering from frailty. There was no distinction made between these unhealthy normal weight people and lean healthy individuals. The overweight and obese groups did appear to have a lower mortality rate than this mix of healthy and very unhealthy normal weighted individuals, and this flaw led to false conclusions that overweight and grade 1 obesity carry no risk and may offer reduced mortality.

View the February 20, 2013 webcast of the panel presented by the Department of Nutrition at Harvard School of Public Health: Does Being Overweight Really Reduce Mortality?

Read more about this study in our “Ask the Expert” with Dr. Walter Willett.

What Causes Weight Gain?

1. Diet: The quantity and quality of food in your diet has a strong impact on weight.

2. Genes: Some people are genetically predisposed to gain weight more easily than others or to store fat around the midsection.

Genes do not have to become destiny, however, and studies suggest that eating a healthy diet, staying active, and avoiding unhealthy habits like drinking soda can prevent the genetic predisposition to risk for obesity. (10)

Read more about genetic risk for obesity on the Obesity Prevention Source.

3. Physical inactivity: Exercising has a host of health benefits, including reducing the chances of developing heart disease, some types of cancer, and other chronic diseases. (11) Physical activity is a key element of weight control and health.

4. Sleep: Research suggests that there’s a link between how much people sleep and how much they weigh. In general, children and adults who get too little sleep tend to weigh more than those who get enough sleep. (12, 13)

  • For example, in the Nurses’ Health Study, researchers followed roughly 60,000 women for 16 years. At the start of the study, all of the women were healthy, and none were obese; 16 years later, women who slept 5 hours or less per night had a 15 percent higher risk of becoming obese, compared to women who slept 7 hours per night. Short sleepers also had 30 percent higher risk of gaining 30 pounds over the course of the study, compared to women who got 7 hours of sleep per night.

There are several possible ways that sleep deprivation could increase the chances of becoming obese.

  • Sleep-deprived people may be too tired to exercise, decreasing the “calories burned” side of the weight-change equation.
  • People who don’t get enough sleep may take in more calories than those who do, simply because they are awake longer and have more opportunities to eat.
  • Lack of sleep also disrupts the balance of key hormones that control appetite, so sleep-deprived people may be hungrier than those who get enough rest each night.

Read more about sleep and obesity.

References:


1. NIH, N.H.L., and Blood Institute November 29, 2010.
2. Rimm, E.B., et al., Body size and fat distribution as predictors of coronary heart disease among middle-aged and older US men. Am J Epidemiol, 1995. 141(12): p. 1117-27.
3. Willett, W.C., et al., Weight, weight change, and coronary heart disease in women. Risk within the ‘normal’ weight range. JAMA, 1995. 273(6): p. 461-5.
4. Colditz, G.A., et al., Weight gain as a risk factor for clinical diabetes mellitus in women. Ann Intern Med, 1995. 122(7): p. 481-6.
5. Huang, Z., et al., Body weight, weight change, and risk for hypertension in women. Ann Intern Med, 1998. 128(2): p. 81-8.
6. Maclure, K.M., et al., Weight, diet, and the risk of symptomatic gallstones in middle-aged women. N Engl J Med, 1989. 321(9): p. 563-9.
7. Eliassen, A.H., et al., Adult weight change and risk of postmenopausal breast cancer. JAMA, 2006. 296(2): p. 193-201.
8. Flegal, K.M., et al., Cause-specific excess deaths associated with underweight, overweight, and obesity. JAMA, 2007. 298(17): p. 2028-37.
9. Flegal, K.M., et al., Association of all-cause mortality with overweight and obesity using standard body mass index categories: a systematic review and meta-analysis. JAMA, 2013. 309(1): p. 71-82.
10. Qi, Q., et al., Sugar-sweetened beverages and genetic risk of obesity. N Engl J Med, 2012. 367(15): p. 1387-96.
11. Haskell, W.L., et al., Physical activity and public health: updated recommendation for adults from the American College of Sports Medicine and the American Heart Association. Med Sci Sports Exerc, 2007. 39(8): p. 1423-34.
12. Patel, S.R. and F.B. Hu, Short sleep duration and weight gain: a systematic review. Obesity (Silver Spring), 2008. 16(3): p. 643-53.
13. Patel, S.R., et al., Association between reduced sleep and weight gain in women. Am J Epidemiol, 2006. 164(10): p. 947-54.

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The aim of the Harvard School of Public Health Nutrition Source is to provide timely information on diet and nutrition for clinicians, allied health professionals, and the public. The contents of this Web site are not intended to offer personal medical advice. You should seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this Web site. The information does not mention brand names, nor does it endorse any particular products.