Chronic overconsumption of sugar-sweetened beverages (SSBs) is amongst the dietary factors most consistently found to be associated with obesity, type 2 diabetes (T2D) and cardiovascular disease (CVD) risk in large epidemiological studies. Studies have shown that SSB overconsumption increases intra-abdominal obesity and ectopic lipid deposition in the liver, and also exacerbates cardiometabolic risk. Similar to the prevalence of obesity and T2D, national surveys of food consumption have shown that chronic overconsumption of SSBs is skyrocketing in many parts of the world,
SSB overconsumption is also particularly worrisome among children and adolescents. SSBs typically include carbonated soft drinks, juice drinks (with added sugars), sports drinks, energy drinks, milkshakes, and iced tea or coffee.
The epidemics of obesity, type 2 diabetes (T2D), and cardiovascular diseases (CVD) are affecting most if not all developed countries around the world. While the prevalence of overweight, obesity, and T2D remain high in North America and Western Europe, obesity rates and T2D rates are increasing at a stunning pace in developing countries. In Mexico City inhabitants aged between 35 and 74 years, the excess mortality associated with previously diagnosed T2D accounted for one third of all deaths between 1998 to 2004.
In some countries such as the Unites States, sugar-sweetened beverages (SSBs) account for almost half of the added sugar consumed nationally and consumption around the world has reached unprecedented proportions, and the rise in the prevalence of cardiometabolic risk factors in children such as abdominal obesity and insulin resistance has increased in parallel.
A recent modelling study performed by the Global Burden of Diseases Nutrition and Chronic Diseases Expert Group (NutriCoDE) estimated that up to 184,000 deaths per year could be attributed to the chronic overconsumption of SSBs [9]. Similar to the prevalence of obesity and T2D, studies analysing national surveys of food consumption have shown that the chronic overconsumption of SSBs is also skyrocketing in many parts of the world.
SSBs are the single greatest source of added sugars in most Western countries. SSBs are typically sweetened with high-fructose corn syrup (HFCS) in the US or sucrose. Sucrose, also often referred to as table sugar, is a disaccharide composed of glucose and fructose linked via a glycoside bond.
One study showed in a six-month parallel intervention study of 47 overweight individuals that the consumption of 1 L/day of sucrose-sweetened beverages (cola) significantly increased visceral adipose tissue and hepatic fat accumulation compared to the consumption of 1 L/day of semi-skimmed milk or water. Although not associated with increases in body weight or total fat mass, the consumption of cola was linked with increases in plasma triglyceride and cholesterol levels. Interestingly, daily total energy intake did not appear to differ across subgroups, thereby suggesting that energy included in beverages could have been compensated for by reductions in energy from other sources.
HFCS is produced by industrial processing of corn starch. It contains two monosaccharides, free fructose, and glucose in various proportions. Both fructose and glucose have different metabolic fates, an observation that has encouraged many to suggest that fructose may have a unique role in the pathogenesis of cardiometabolic diseases. This hypothesis has been supported by well-designed controlled studies
In a 10-week randomized clinical trial fed an ad libitum diet with 25% of calories originating from glucose- or fructose-sweetened beverages. Although both diets increased body weight, only participants in the HFCS group had increased visceral adipose tissue accumulation at the end of the trial. Insulin levels during a 3-h oral glucose tolerance test increased by 27% in the fructose group (significant) and by approximately 14% in the glucose group (nonsignificant). Similarly, 24-h post-meal triglyceride and fasting apolipoprotein B levels, as well as small, dense low-density lipoprotein (LDL) levels and triglyceride levels all increased in the fructose but not in the glucose group following the intervention.
About a dozen large prospective epidemiological studies have documented the association between SSB consumption and the risk of cardiometabolic diseases such as obesity, metabolic syndrome, T2D, and CVD.
A meta-analysis on 2013 that included 25,745 children and adolescents from 15 prospective studies and 174,252 adults from in seven prospective studies suggest that a one serving per day increase in SSB is associated with a 0.06 unit increase in body mass index (BMI) per year in children and adolescent and with a 0.12 to 0.22 kg yearly weight gain in adults. The same group also published evidence that SSBs overconsumption is linked with the onset of the metabolic syndrome (a constellation of CVD and T2D risk factors associated with abdominal obesity and insulin resistance) and T2D.