This is the conclusion of a recent meta-analysis made by scientists at the Harvard School of Public Health. For the first time it supplies empiric evidence that sugar-sweetened soft drinks present a potential risk – also for the health of your teeth and for cardiovascular diseases.
They are supposed to refresh, bring new energy and of course – we almost forgot – to quench thirst: Lemonades, fruit drinks, energy drinks, vitamin juices, ice teas & Co. It’s no problem at all to extend this list since the range of soft drinks by now is diversified. But it doesn’t matter which of those countless “soft” beverages you consume, they all have one thing in common – they contain sugar. And that provides them with a health explosive – something a recent study at the Harvard School of Public Health shows. Whether we are talking fructose, glucose, corn syrup or fruit juice concentrate: The metabolic effects are fatal.
Soft drinks boom worldwide
All around the globe, sugar-sweetened thirst quenchers, the so-called sugar-sweetened beverages (SSB) enjoy a permanently increasing popularity. For example in the US, the consumption has more than doubled from the late seventies until 2006 – and thus the average consumption of calories through soft drinks from back then 64 to 142 calories daily. This boom is particularly marked in aspiring emerging countries like India or China. According to the annual report of the Coca-Cola group, sales of its soft drinks in 2007 increased by 14 percent in India and in China by 18 percent. And absolutely problematic trend, as the results of the nutritional scientific meta-analysis of Dr. Vasanti Malik and his team show. “A number of prospective epidemiological studies already prove that there is a direct association between gaining weight, overweight and obesity and the consumption of sugar-sweetened soft beverages”, confirms the head of the study, Dr. Malik. This association also applies regarding an increased risk for diabetes type 2 and the metabolic syndrome. Researchers here demonstrate a “growing evidence” as the Boston nutritionist puts it.
Damaging on many levels
One of the crucial points in SSBs is the high content of fast absorbable complex carbon hydrates like glucose and fructose. Those increase on one hand the risk to get diabetes type 2 and the metabolic syndrome since they promote the development of overweight. On the other hand – according to Dr. Malik – they increase “the glycemic encumbrance which leads to glucose intolerance, insulin resistance and a disturbed function of the beta-cells”. In addition the concentration of inflammatory marker increases like for example the C-reactive protein.
As Dr. Malik’s team colleague Professor Dr. Frank Hu explains, there are even more dangers hiding in the sugar-sweetened beverages: “The metabolic effect of SSBs causes also high blood pressure and a higher deposition of visceral fat”. And the later as well hides – as several recent studies prove – an enormous danger for health. And that is by far not everything soft drinks can do to you. According to Professor Hu, they also increase the hepatic lipogenesis which shows in a rise of triglycerides and LDL-cholesterol. On the other hand, the HDL-cholesterol concentration decreases. Just how damaging this synergy of all these effects is, displays the meta-analysis of the Harvard scientists. Dr. Malik: “For the first time it supplies a complete overview of the extent of the risk and its high evidence”.
“Relevant risk factor…”
For the meta-analysis, Dr. Malik’s team analyzed the data of eleven studies – eight of them examined the association between SSBs and diabetes type 2, the other three the association between SSBs and the metabolic syndrome. The eight diabetes studies included a total of 310,819 participants and 15,043 cases of diabetes type 2. The three studies regarding the metabolic syndrome were done with a total of 19,431 test persons and 5,803 cases. “The cohorts included male and female adults of both, white and black, from the US as well as from Finland, Singapore and China among others”, says Professor Hu. In the diabetes studies, the pooled relative risk (RR) was 1.26 (1.12 – 1.41); in the studies in regard to the metabolic syndrome, the pooled RR was at 1.20 (1.02 – 1.42). The evaluation of the data revealed that the consumption of one or two glasses of sugar-sweetened beverages daily increases the risk for diabetes type 2 by 26 percent. The risk for the metabolic syndrome increases by 20 percent with one or two glasses a day. The amount of fluid per glass was defined with about 200 milliliters.
The conclusion of the scientists at the Harvard School of Public Health: Consequently, sugar-sweetened beverages are a risk factor to be taken very seriously, especially since – as Dr. Malik puts it: “The frequent consumption of SSBs is also to be seen as a marker for an unhealthy nutrition in general with a high share of trans-fats, saturated fatty acids and little dietary fibers”. The risk of consuming sugar-sweetened beverages can be modified easily though: Drink healthy alternatives like water or non-sweetened herbal teas to cover your need for fluid.