Higher genetic risk of obesity incidence due to the consumption of sugar-sweetened beverages

Obesity has emerged as a major menace to the health of the public all over the world. There were many alterations in the lifestyle as well as the diet of several people all over the world for the past 30 years showing impact on the initiation of obesity. The consumption of sugar-sweetened beverages has gone very high. There are lot of evidences which say that there is a positive link between the risk of obesity and the intake of sugar-sweetened beverages. Several research studies that were conducted in the past few years have shown that many loci are associated with the body mass index (BMI). These gene loci are variants that are distributed commonly and they define the vulnerability of the person to obesity.

Several genomewide associated studies were considered to be used for a meta-analysis to determine that there are 32 loci that are linked with BMI. Some of the research studies have discussed about the association of certain environmental factors with the genetic-predisposition for fat deposition. As the intake of sweetened beverages is going high, the prevalence of obesity also increased almost twice in the United States from the 1070s. From the data obtained from several other related studies, the investigators of this research study have hypothesized that the relationship between the genetic- predisposition and adiposity can be influenced by excessive consumption of sugar-sweetened beverages.

The hypothesis was tested by using a data to evaluate the interaction of the genetic predisposition score with the consumption of sweetened beverages. The genetic-predisposition score was calculated depending on the 32 loci that are associated with BMI. The relation of the interaction between beverages consumption and the above score with the BMI and the obesity stimulation in men and women from the Nurses’ Health Study (NHS) and Health professionals Follow-up Study (HPFS) was examined in this study. Similar analysis was performed in another group taken from Women’s Genome Health Study (WGHS).

The sugar-sweetened beverages that were included in the questionnaire to assess the people in the cohorts of HPFS and NHS are caffeinated colas, carbonated non-cola soft drinks, caffeine-free colas and non-carbonated sugar-sweetened beverages. The artificially sweetened beverages that were used for the questionnaire are non-carbonated low-calorie beverages, caffeinated beverages and caffeine-free beverage. The body mass Index (BMI) was calculated by dividing the weight with the square of height. People with BMI greater than 30 were considered as obese individuals. The information regarding the body weight, height and lifestyle related elements were obtained through questionnaires. The quality of diet was evaluated using alternative healthy eating index. The physical activity, medical history, dietary factors and weight of the people from the WGHS group were evaluated using the questionnaires given at baseline and at follow-up. The single nucleotide polymorphisms were selected on behalf of 32 loci which were associated with BMI.

Among the participants from NHS and HPFS groups, those who have taken more of sugar-sweetened beverages had strong association with genes, calculated from the genetic predisposition score than those who have taken low quantities. In the above groups, with the addition of 10 risk alleles, the BMI increase was evaluated as 1.00 when the sugar-sweetened beverages are served for less than once in a month (first category), 1.2 when the beverages are served for 1 to 4 times in a month (second category), 1.37 when 2 to 6 servings were done per week (third category) and 1.85 when more than one serving is done in a day (fourth category). In the case of WGHS group, the four categories represented the BMI as 1.39, 1.64, 1.90 and 2.53 for the addition of 10 risk alleles.

The comparative risks of obesity initiation when 10 risk alleles are added every time in the NHS and HPFS groups was 1.19 when the sugar-sweetened beverages were consumed for one time in a month. The obesity incidence was 1.67 in the second category, 1.58 in the third category and 5.06 in the fourth category. In the WGHS group, with the addition of ten risk alleles the obesity initiation was 1.4, 1.5, 1.54 and 3.16 in the first, second, third and fourth categories respectively. The relative risk of obesity incidence in all the three groups for an increment of 10 risk alleles were 1.35, 1.59, 1.56 and 3.35 in the four categories in the above given order. The relationship between the sugar-sweetened beverage intake and the BMI was solid and tough in people who had the genetic predisposition score in the highest quartile (beta coefficient= 0.44). The relation was weaker if the score was lying in the lowest quartile (beta coefficient= -0.07).

Conclusion:

The study offers proof from three different groups that intake of high quantities of sugar-sweetened beverages will lead to the genetic predisposition for higher risk of obesity and increased BMI.

References:

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, and Lu Qi. Sugar-Sweetened beverages and Genetic risk of obesity. N Engl J Med 2012; (10.1056/NEJMoa1203039) Published in the website

http://www.nejm.org/doi/full/10.1056/NEJMoa1203039?query=featured_home#t=articleTop