Outlook: Obesity Epidemic

NOVEMBER 01, 2007
Susan Farley

Ms. Farley is a freelance medical writer based in Wakefield, RI.

Just the Facts: Breaking Down the Obesity?Incontinence Link

  • Women with body mass index (BMI) ≥35 were 2 times as likely to develop urinary incontinence as women with BMI <23
  • A weight gain of 11.2 to 22 lb after age 18 makes a woman 44% more likely to be incontinent
  • A weight gain of 66 lb increases a woman's likelihood of incontinence by 4 times
  • Up to 40% of women under age 60 may have a urinary incontinence problem
  • Losing weight has been shown to improve urinary control

Glycemic Index Diets Successful in Short Term

An Australian review of 6 clinical trials found that diets relying on the Glycemic Index (GI) effectively achieved weight loss among overweight and obese adults in the short term.

The GI relies on the effects that certain foods have on blood sugar levels. Foods that are high on the GI include white bread, potatoes, and rice. Foods low on the GI include beans, yogurt, and highfiber grains.

Dieters are recommended to eat foods lower on the index.

While there was not a huge difference in weight loss with low—GI diets—2 lb more weight loss, on average—the diet appears to be effective in the short term. Dieters should be aware, however, that the question of the long-term effectiveness of this approach has yet to be determined.

Is WHR More Significant Than BMI?

Which is the better predictor of heart disease: waist-to-hip ratio (WHR) or BMI? A new study suggests that WHR can more accurately predict one's propensity to developing heart disease. According to researchers, even a small potbelly is associated with a higher risk of developing arterial plaque.

A thicker waist will have a greater impact on the risk of cardiovascular disease, even if BMI is normal. As people age, they need to be more aware of weight gain in the midsection.

Researchers studied BMI, WHR, and WC (waist circumference). Results show the following:

  • Those in the top 5th for their WHR were nearly twice as likely to have calcium deposits as those in the bottom 5th for WHR
  • WHR had a stronger link to coronary artery calcium prevalence than BMI and WC in men and women
  • People in the top 5th for WHR were 3 times more likely to have aortic plaque than those in the bottom 5th for WHR

Link Between Obesity and Migraine Questioned

Another study has emerged refuting claims that there is a link between obesity and migraine headaches. The Swedish study looked at women aged 40 to 74 to find an association between high BMI and incidence of migraines. Results did not detect any link, showing that 32% of obese women and 38% of nonobese women had active migraines—not a significant difference. Investigator Dr. Peter Mattsson of the University Hospital in Sweden noted, "If there are true associations between obesity and features of migraines such as frequency, these are likely to be small and cannot be reliably studied in small or moderately sized community samples."

Vertigo Drug Doubles as Weight-loss Drug

Researchers at the Tel Aviv University Sackler School of Medicine along with the drug company Obecure have developed Histalean, a weight-loss drug based on the vertigo drug betahistine. Available for more than 30 years, betahistine blocks the histamine1 and histamine3 receptors in the brain, which are connected to the sense of feeling full and one's desire to eat fatty food. Results of Histalean use were more significant in women. Women under the age of 50 who took the drug for 12 weeks lost 7 times more weight than those who took the placebo. According to 1 study participant, taking the pill "wasn't hard."

The Latest on Good Fat/Bad Fat

Harvard researchers reviewed data from 2 large-scale epidemiologic studies— the Nurses' Health Study and the Health Professionals Follow-up Study— and came to some updated conclusions on the state of fat in one's diet:

  • Switching over some of one's daily intake of carbohydrates to unsaturated fat (vegetable oils) will result in lower low-density lipoprotein (LDL; "bad") cholesterol levels and higher high-density lipoprotein (HDL; "good") cholesterol levels.
  • 1 g fat = 9 calories; 1 g carbs = 4 calories
  • Saturated fat—found in meat and dairy products—causes increases in LDL cholesterol as well as increases in HDL cholesterol. The increase in HDL levels, however, is not enough to counter the effects of the increased LDL levels.
  • Replacing 5% of total calorie intake with polyunsaturated fat would lower the risk of heart disease by 30% to 40%
  • Trans fat raises LDL cholesterol, lowers HDL cholesterol, and makes blood platelets "stickier," thereby promoting LDL particles that damage arteries and raising the risk of blood clots, diabetes, gallstones, dementia, heart disease, and infertility
  • Trans fat (also known as "metabolic poison") is created by adding hydrogen atoms to vegetable oils
  • Federal guidelines state that up to 35% of total calories can come from fat. Dr. Walter Willett of Harvard's School of Public Health says that up to 40% is okay.
  • Saturated fats should be limited to about 17 g per day. As a frame of reference, a 7-oz cheeseburger has 12 g and a scoop of ice cream has about 10 g.