The population group in this study consisted of 32,575 women aged 49−83 and 35,884 men aged 45−79 who were healthy without symptoms of cardiovascular disease, cancer, or diabetes at the start of the study. The group was followed for an average of 10 years and the consumption of sugar sweetened beverages including sugar-sweetened and artificially sweetened soft drinks and juice drinks, was assessed by using a food-frequency questionnaire.
The findings of the study revealed 3510 incident cases of stroke, including 2588 cerebral infarctions, 349 intracerebral hemorrhages, 156 subarachnoid hemorrhages, and 417 unspecified strokes and linked the consumption of sweetened beverage consumption with risk of total stroke and cerebral infarction.
A study from the Harvard School of Public Health, published earlier this year, determined that consumption of sugar sweetened beverages (SSBs) is linked to genetic changes causing an increased risk of obesity, illustrating the depth and complexity of the public health epidemic that the United States faces.
“Our study for the first time provides reproducible evidence from three prospective cohorts to show genetic and dietary factors — sugar-sweetened beverages — may mutually influence their effects on body weight and obesity risk. The findings may motivate further research on interactions between genomic variation and environmental factors regarding human health,” said Lu Qi, assistant professor in the Department of Nutrition at HSPH and senior author of the study.
The research study consisted of a large population group including 121,700 women in the Nurses’ Health Study, 51,529 men in the Health Professionals Follow-up Study and 25,000 in the Women’s Genome Health Study. All of the research participants completed food-frequency questionnaires detailing their food and drink consumption over time.
In addition the researchers examined data from 6,934 women from NHS, 4,423 men from HPFS, and 21,740 women from WGHS who were of European ancestry and for whom genotype data based on genome-wide association studies were available. Participants were divided into four groups according to how many sugary drinks they consumed: less than one serving of SSB per month, between 1-4 servings per month, between 2-6 servings per week, and one or more servings per day. To represent the overall genetic predisposition, a genetic predisposition score was calculated on the basis of the 32 single-nucleotide polymorphisms known to be associated with BMI (weight in kilograms divided by the square of the height in meters).
The research findings quite clearly revealed that BMI and obesity risks among those who drank one or more sugar sweetened beverages per day increased the genetic risk to obesity by 50%. Individuals who already have an increased genetic predisposition to obesity are impacted more substantially by the harmful effects of SSBs on BMI.
“SSBs are one of the driving forces behind the obesity epidemic,” said Frank Hu, professor of nutrition and epidemiology at HSPH and a coauthor of this study. “The implication of our study is that the genetic effects of obesity can be offset by healthier food and beverage choices.
“Although ours is the first study to show this relationship, it is not surprising to see that women who drank more sugar-sweetened beverages had a higher risk of estrogen-dependent type I endometrial cancer but not estrogen-independent type II endometrial cancer,” said Maki Inoue-Choi, Ph.D., M.S., R.D., who led this study as a research associate in the Division of Epidemiology and Community Health of the University of Minnesota School of Public Health in Minneapolis. “Other studies have shown increasing consumption of sugar-sweetened beverages has paralleled the increase in obesity. Obese women tend to have higher levels of estrogens and insulin than women of normal weight. Increased levels of estrogens and insulin are established risk factors for endometrial cancer.”
The study group consisted of 23,039 postmenopausal women who reported dietary intake, demographic information, and medical history in 1986, prior to the cancer diagnosis, as part of the Iowa Women’s Health Study.The rate of sugar sweetened beverage consumption was evaluated by four questions asking usual intake frequency of sugar-sweetened beverages, including 1) Coke®, Pepsi®, or other colas with sugar; 2) caffeine-free Coke®, Pepsi®, or other colas with sugar; 3) other carbonated beverages with sugar (e.g., 7-Up®); and 4) Hawaiian Punch®, lemonade, or other noncarbonated fruit drinks.
“Sugar-free soft drinks” included low-calorie caffeinated and caffeine-free cola (e.g., Pepsi-Free®), and other low-calorie carbonated beverages (e.g., Fresca®, Diet 7-Up®, and Diet Ginger Ale®).
The scientists divided the sugar-sweetened beverage consumption patterns of these women into quintiles, ranging from no intake (the lowest quintile) to between 1.7 and 60.5 servings a week (the highest quintile).
Between 1986 and 2010, 506 type I and 89 type II endometrial cancers were recorded among the women Inoue-Choi and colleagues studied. They did not find any association between type I or type II endometrial cancers and consumption of sugar-free soft drinks, sweets/baked goods, and starch.
“Research has documented the contribution of sugar-sweetened beverages to the obesity epidemic,” said Inoue-Choi. “Too much added sugar can boost a person’s overall calorie intake and may increase the risk of health conditions such as obesity, diabetes, heart disease, and cancer.”
Another research study has also found a direct causal link to depression and diet soda.
Researchers profiled more than 260,000 older adults in a U.S. survey, and determined that people who consumed at least four daily servings of artificially sweetened soda, iced tea or fruit punch were at increased risk, (31%), of being diagnosed with depression in the next decade.
Sugar sweetened drinks were also implicated in a causal link with a higher depression risk of 22% but the findings were weaker compared to the link between diet soda and depression.
Dr. Honglei Chen, an investigator at the U.S. National Institute of Environmental Health Sciences, found the research findings ““intriguing,” and consistent with a small but growing number of studies linking artificially sweetened drinks to poorer health.
The results were released by the American Academy of Neurology, ahead of its annual meeting in San Diego in March.
The American Beverage Association (ABA), which represents soft drink manufacturers, has criticized the research.
“This research is nothing more than an abstract — it has not been peer-reviewed, published or even, at the very least, presented at a scientific meeting,” the ABA said in a news release. “Furthermore, neither this abstract nor the body of scientific evidence supports that drinking soda or other sweetened beverages causes depression. Thus, promoting any alleged findings without supporting evidence is not only premature, but irresponsible.”
National Institutes of Health
Honglei Chen, M.D., Ph.D., investigator, epidemiology branch, U.S. National Institute of Environmental Health Sciences; Eva Redei, Ph.D., professor, psychiatry, Northwestern University Feinberg School of Medicine, Chicago; American Beverage Association, news release, Jan. 8, 2013; news release, American Academy of Neurology, Jan. 8, 2013.
M. Inoue-Choi, K. Robien, A. Mariani, J. R. Cerhan, K. E. Anderson. Sugar-Sweetened Beverage Intake and the Risk of Type I and Type II Endometrial Cancer among Postmenopausal Women. Cancer Epidemiology Biomarkers & Prevention, 2013; DOI: 10.1158/1055-9965.EPI-13-0636
Qibin Qi, Audrey Y. Chu, Jae H. Kang, Majken K. Jensen, Gary C. Curhan, Louis R. Pasquale, Paul M. Ridker, David J. Hunter, Walter C. Willett, Eric B. Rimm, Daniel I. Chasman, Frank B. Hu, Lu Qi. Sugar-Sweetened Beverages and Genetic Risk of Obesity. New England Journal of Medicine, 2012; 120921130020003 DOI: 10.1056/NEJMoa1203039
Susanna C. Larsson, Agneta Åkesson, and Alicja Wolk. Sweetened Beverage Consumption Is Associated with Increased Risk of Stroke in Women and Men. J. Nutr. June 1, 2014 vol. 144 no. 6 856-860