Dieters' nightmare comes true
People who diet and try to lose weight are more likely to experience major weight gain than nondieters. In a large Finnish study, risk was greatest among younger men and women. Over a period of 15 years, 36 percent of the dieting younger men had gained over 10 kg (22.5 pounds), compared with 29 percent of nondieting men in that age group. In 15 years, 24 percent of dieting women in their middle years gained over 10 kg, versus 13 percent of nondieters. Initial weight made no difference. Neither did other potential confounders including smoking, alcohol use, education level, or marital status. The study was based on a twin population of 3,536 men and 4,193 women. In comparing twins, the tendency to gain weight following weight loss was found to have a family component.
   The authors cite two US studies with similar results: the Healthy Worker Project, in which a dieting history at baseline predicted weight gain in 3,553 men and women over 2 years, and the Health Professionals Follow-Up Study of 19,478 men, in which frequent dieting was related to weight gain. (Healthy Weight Journal 2000:14:4;51/ Korkeila M, Rissanen A, Kaprio J, et al. Weight-loss attempts and risk of major weight gain. Am J Clin Nutr 1999;70:965-973)

Cold weather births
Adult obesity is linked both to high birth weights and to early cold exposure in a study of 1,750 men and women born in Hertfordshire, England, between 1920 and 1930. For both men and women, body mass index (BMI) rose with increasing birth weight. For men, the climate at time of birth had an effect. BMI was greater among those born in the first half of the year, Janury to June, than among those born in July to December. The relationship between birth weight and adult obesity was also stronger in men and women born in the first 6 months of the year or following cold winters than in those born in the last half of the year or following mild winters. (Healthy Weight Journal 2000:14:4;51 / Phillips DIW, Young JB. Birth weight, climate at birth and the risk of obesity in adult life. Int J Obes Relat Metab Disord 2000;24:281-287)

Gene linked to weight retention after childbirth
A single gene may be involved in both high body weight in women after childbirth and in low birth weight of infants. Research in Germany based on genotyping of 792 women found that those with their first child who are homozygous carriers of the 825T allele of the gene encoding the beta-3 subunit of heterotrimeric G proteins (GNB3) have a high risk of retaining much of the weight gained during pregnancy. Highly active women with the gene avoided this risk. The same gene appears to be associated with low birth weight in infants who are otherwise not at high risk. The results are consistent with the idea that the GNB3 825T allele is a marker of adverse metabolic phenotypes, says an accompanying editorial. (Healthy Weight Journal 2000:14:4;51 / Reuters Health 4/7/00; Lancet 2000;355:1201, 1240-1242)

Shiftwork increases weight
   Men who work rotating shifts tend to be heavier and to have more abdominal fat than daytime workers in the same companies, according to a study of 377 workers in The Netherlands. The longer they had worked a shift, the more pronounced was this effect. Statistical differences in waist-hip ratio were found between men who had worked shifts for 2 or more years and those who never worked shifts. But differences did not become significant for body mass index until the men had worked 5 years or more. The effect was in the same direction but not significant for women. A study cited by the researchers found an excess weight gain due to night work of nearly 1 kg per 5 years. They suggest that there may be a link between this weight gain and research showing higher heart disease risk for shift workers. Whether this weight and fat distribution change reflects changed diet or activity, increased stress, possible metabolic disturbances, or an effect of circadian rhythm on digestive processes or insulin secretion is not clear. (Healthy Weight Journal 2000:14:1;3 / Van Amelsvoort LGPM, Schouten EG, Kok FJ. Duration of shiftwork related to body mass index and waist to hip ratio. Int J Obesity 1999;23:973-978)

Is weight loss after 50 inadvisable?
 Instead of urging older people to lose weight, a better public health emphasis might be to inform them  that substantial weight loss after age 50 is a potential indicator for poor survival, says a major new study.
   Supported by the National Heart, Lung, and Blood Institute, the long-term heart study involves instituions including the National Institute on Aging, at several locations, with a coordinating center at the University of Washington, Seattle. It looked at 4,317 nonsmoking adults over age 65 in four counties in the United States, who recalled their weight at age 50.
   The data show that for these adults there is little relation between weight and mortality, except for those with a very low weight (BMI of 20 or below), who have higher death rates. A low BMI was associated with mortality even after control for a wide variety of measures, including short-term unintended weight loss. A high BMI showed no association with mortality, and the variables considered had little effect except that long-term weight loss had a profound effect on results. People who lost 10 percent of their obdy weight after age 50 had a relatively high death rate. When that group was excluded, there was no remaining relationship between body mass index and mortality. During the 5-year study, 12.5 percent of the participants had died (about twice as many men as women).
   The researchers conclude that this finding of no excess risk for a BMI above 27 would seem to support advising higher weights for older adults. (Healthy Weight Journal 1999:13:3;34 / Diehr P, Bild D, Harris T, et al. Body mass index and mortality in nonsmoking older adults. Am J Public Health 1998;88:623-629)

Weight cycling in Iowa women
   Weight gain, loss, and variability are associated with higher risk for myocardial infarction, stroke, diabetes, and hip fracture independent of weight (body mass index) in the Iowa Women's Health Study. This is a population-based sample of 33,834 women age 55 to 69, free of cancer and heart disease who reported recalled weights at ages 18, 30, 40, 50, and currently. The majority of women gained weight over time: 33 percent had large gain; 15 percent small gain; 12 percent large cycle; 6 percent small cycle; 3 percent no change; 5 percent weight loss; 26 percent, other weight patterns. In fully adjusted models, associations between weight variability and myocardial infarction, stroke, and diabetes were similar in overweight and normal weight women. All weight change categories had a higher risk of diabetes, compared with small gain or risks of diabetes and breaset cancer (in these post-menopausal women). Weight loss also was associated with diabetes and with hip fractures. (Healthy Weight Journal 1998:12:5;67 / French S, et al. Weight variability and incidnt disease in older women: the Iowa Women's Health Study. Int J Obes 1997; 21:217-223)

Psychiatric drugs cause weight gain
Depression is often associated with loss of appetite and weight. Treatment with antidepressants restores mood, but may also promote weight gain. Previously, this was seen as a sign of improvement, but today's patients complain, citing weight gain as a reason for non-compliance with drug therapy. Many also blame their medications for "carbohydrate craving," saying they had preference changes to sweet, high-fat foods leading to weight gain. 
Researchers investigating this did find weight gain with various drugs. But they believe the cause was probably not a change in food intake, but rather from lower energy expenditure induced by the medications.
They also found food preference changes -- not related to drugs, but earlier during the depression that preceded drug treatment.
The University of Pittsburgh researchers administered a food preference questionnaire to depressed patients two to three times during the pre-medication period and monthly during antidepressant treatment. More than one- third increased their cravings for sweet, high-fat foods in the initial stages.
Initial BMI was about 23, with gains in one month of a BMI of 1.3 with amitriptyline, .72 with nortriptyline, .68 with desipramine. In contrast, zimelidine (which is no longer prescribed) did not promote weight gain. (Healthy Weight Journal 1997:11:6;105 / Fernstrom M, Psychiatric drugs and weight gain. In Progress in Obesity Research:7, edit A. Angel et al, 1996;641-647. John Libbey & Co. London, England)

Mauritius islanders gain weight
Alarming increases in diabetes, and one of the world's highest coronary heart disease mortality rates, fuel concerns over the rise in obesity in the rapidly developing island nation of Mauritius. 
East of Madagascar in the Indian Ocean, Mauritius has pursued an intensive health promotion program advocating healthy diet and exercise. 
Yet in the five years between 1987 and 1992, over weight on the island has increased from 26 to 36 percent in men and 38 to 48 percent in women (BMI of 25 or more). Obesity (BMI of 30 or more) increased from 3 to 5 percent for men and 10 to 15 percent for women. Abdominal obesity increased from 14 to 20 percent in men and from 14 to 21 percent in women. 
Prevalence varies among the three main ethnic/racial groups. Creoles, of African heritage, have the highest rates of obesity (8 percent for men and 20 percent for women); Indians intermediate; and Chinese the lowest (2 percent for men and 6 percent for women). Abdominal obesity is greatest in Indian men and Creole women. 
That women gained more than men may be due to lower physical activity and weight gain in pregnancy, say the researchers. Lower income women gained more weight. Smoking cessation was a factor for weight gain in men, but not women, as few smoke. 
Younger, leaner adults gained more than older adults. The researchers conclude that younger, slimmer, lower income islanders are at most risk for continued weight gain. (Healthy Weight Journal 1997:11:6;106 / Hodge AM, et al. Increasing obesity in Mauritius. I J Obesity 1996;20:137-146.)

Diabetes treatment and obesity: a dilemma
Obesity is a major risk factor for the development of type 2 diabetes, and weight loss is often recommended. Yet conventional treatments with insulin and sulphonylureas often lead to weight gain, points out Gareth Williams, MD, of the University Hospital Aintree, Liverpool, UK. Thus, he sees managing a patient with type 2 diabetes and obesity as a "conflict of interests." Current estimates are that the incidence of type 2 diabetes will increase by 50 percent over the next 7 or 8 years, bringing the total number of people worldwide with the disease to 150 million. This is a dilemma that needs to be recognized and dealt with, says Williams. (Healthy Weight Journal 1999:13;6;82 / Williams G. Obesity and type 2 diabetes: a conflict of interests? Int J Obes Relat Metab Disord 1999; 23 Suppl 7:S2-S4.)

Alcohol increaes waist-to-hip ratio
In a representative sample of French men and women, the more alcohol they drank, the larger their waist-to-hip ratio and waist girth. This was independent of body mass index, age, physical activity, socioeconomic level, and smoking.
Total alcohol consumption was what mattered, not whether it was wine, beer, or spirits. (The French drink more wine than any other alcoholic beverage, at 67 percent of total alcohol intake.) There was no protective effect of wine against abdominal fat disposition. This disputes the common belief that drinking beer promotes abdominal fat distribution whereas wine does not. The study suggests a specific effect of alcohol on abdominal fat deposition, the researchers said. (Healthy Weight Journal 1999:13:6;82 / Dallongeville J, Marecaux N, Ducimetiere P, et al. Influence of alcohol consumption and various beverages on waist girth and waist-to-hip ratio in French men and women. Int J Obesity 1998; 1178-1183.)

Weight cycling hikes gallstone risk
Risk for gallbladder surgery increased with weight cycling, independent of weight, for 47,153 women who were followed over 16 years in the Nurses' Health Study.
Weight cycling of more than 10 pounds of weight loss and regain led to a 31 to 68 percent increase in the risk for cholecystectomy or surgical removal of the gallbladder.
Of the women, 55 percent had at least one cycle of weight loss associated with regain during the 16 years (1972-1988). Only 11 percent kept a stable weight. Compared with stable weight, the risk for gallstones was increased 31 percent in moderate cycling and 68 percent in severe cycling (intentional loss of 20 pounds or more). It was increased 61 percent with weight loss alone. However, risk did not increase with more weight cycling episodes. Inentional weight loss was associated with higher risk for gallstones than unintentional loss. Controlling for weight, dietary fat intake, alcohol intake, smoking, and age made little difference. Obesity and rapid weight loss are also known risk factors for gallstone disease.
The researchers emphasize the importance of maintinaing a stable weight in adulthood, even for large persons: "Our data suggest that obese persons should be advised about the risks of weight fluctuation and counseled to adopt lifestyle changes that have the greatest likelihood of achieving stable weight". (Healthy Weight Journal 1999:13:6;82 / Syngal S, Coakley EH, Willett WC, et al. Long-term weight patterns and risk for cholecystectomy in women. Ann Intern Med 1999; 417-477.)