Looking into the lifestyles of the past to how we live today, there are numerous differences that many people can name off the bat. One thing is for sure is that we are raising and living in a generation that has become more sedentary. The CDC reports the prevalence of obesity to be 39.8% and has affected about 93.3 million of US adults in 2015-2016. This percent is almost half! It is safe to say that for this reason, a national campaign was created to promote a healthy, active lifestyle through the celebrities like Michelle Obama’s “Lets Move” campaign to Ellen DeGeneres. Most people talk about being active to combat this disease but change needs to occur in a person’s diet. With fast food being on every corner, it allows accessibility and ease for full-time working parents to feed their kids. What does that entail? Well recent studies have shown that sugary drinks in conjunction with protein-rich meals can have adverse effects. A sugar sweetened drink with that meal can lead to a negative effect on energy balance, alter food preferences and cause the body to store more fat.

The reason for this change in metabolism is people are affecting the energy balance equation. A sugar-sweetened drink decreased fat oxidation, which is what kick-starts the breakdown of fat molecules after a meal (Casperson et al. 2017). A proposed cycle that causes this metabolic disorder involves the glucose-fatty acid cycle which helps explain why glucose is inhibited by fatty acids because they become glucose intolerant. This inactivates insulin which normally will signal to get rid of the excess glucose, but the body reacts instead by increasing the glucose uptake by muscle and adipose tissue accompanied by increased lipolysis and increased hepatic glucose production (Hue and Taegtmeyer 2009). Impairment of glucose metabolism by fatty acid oxidation was mediated by short term inhibition of several glycolytic steps mainly PFK-1 and PDH (Randle 1998). Fatty acid oxidation leads to an increase in acetyl CoA and NADH which will inhibit PDH complex which leads to an accumulation of cytosolic citrate inhibiting PFK-1. This leads to more inhibition of eventually hexokinase. The mechanisms for glycolysis to use the sugar is now being inhibited, and glycogenesis will take it and store it away as fat reserves. 

Most people when they go out to eat at fast food restaurants will accompany their burger with a nice cold soda, which that soda is the largest single source of sugar in the American diet. Limitations of this study were that the research measured dietary changes for a short time so as to apply their data to a long-term hypothesis should be done with caution. The study expresses caution with interpreting data as their participants were conducted with healthy-weight adults as opposed to overweight individuals. The age group of this study was conducted on individuals around 23 years old, I think they should open or conduct more studies that analyze participants during puberty to see the effects on this diet on metabolism at this age.

References

BioMed Central. (2017, July 21). Why sugary drinks and protein-rich meals don't go well together. ScienceDaily. Retrieved November 18, 2018 from www.sciencedaily.com/releases/2017/07/170721101314.htm

Hue L, Taegtmeyer H. The Randle cycle revisited: a new head for an old hat. Am J Physiol Endocrinol Metab. 2009;297:E578–91.

Randle, P. J. (1998), Regulatory interactions between lipids and carbohydrates: the glucose fatty acid cycle after 35 years. Diabetes Metab. Rev., 14: 263-283. doi:10.1002/(SICI)1099-0895(199812)14:4<263::AID-DMR233>3.0.CO;2-C

Shanon L. Casperson, Clint Hall, James N. Roemmich. Postprandial energy metabolism and substrate oxidation in response to the inclusion of a sugar- or non-nutritive sweetened beverage with meals differing in protein content. BMC Nutrition, 2017; 3 (1) DOI: 10.1186/s40795-017-0170-2