Diet sodas offer a convenient option to high sugar soft drinks and sugar laden beverages, specially for those trying to manage their weight, diabetes or generally reduce sugar. Carbonated water, low calorie sugar substitutes, flavours, caffeine, citric and phosphoric acid are the main ingredients in most diet sodas.
However, the increase and widespread use of non-caloric sweeteners and diet sodas seems to be coinciding with the growing epidemic of obesity and diabetes. Also, concerns regarding the safety of diet drinks is mounting. As a result, whether these really help save you from obesity, diabetes and metabolic syndrome, have become areas of research. Do artificial sweeteners and diet sodas actually help reduce weight? Surprisingly, epidemiological data suggests the contrary. Several large scale prospective studies found a positive correlation between low calorie sugar substitutes and weight gain. The San Antonio Heart study examined 3682 adults over seven to eight year period during 1980s. Drinkers of artificially sweetened beverages consistently had higher BMIs (body mass index) at the follow-ups. Similar results were reported in The American Cancer Society study in 1980s including about 79,000 women and the Nurses Health study including 31,940 women in 1970s. Studies including children also reported similar results. Further, studies suggest that artificial sweeteners and diet sodas do not help reduce weight when used alone. Weight loss is attributed to caloric restriction.
A study done in over 6000 individuals in U.S. published in the journal ‘Diabetes Care’ in 2009 reported that daily consumption of at least one diet soda was associated with signi?cantly greater risk of type 2 diabetes and metabolic syndrome — a cluster of conditions that includes high blood pressure, excess weight gain around the waist, high cholesterol and insulin resistance. Another recent population-based cohort study published in ‘Journal of General Medicine’ in 2012 done on about 2500 individuals reported increased incidence of heart disease with daily consumption of one or more diet sodas.
Several mechanisms for the above have been suggested. First, it has been hypothesized that artificial sweeteners may increase a desire to indulge in sweets and more high calorie foods. Second, over-consumption of other foods or beverages may also occur in conjunction with diet sodas owing to overestimation of the number of calories saved by substituting diet sodas for regular sugar sweetened ones. Interestingly, evidence suggests that artificial sweeteners do not activate the food reward pathways in the same fashion as natural sweeteners. Perhaps, lack of calories generally eliminates the feeling of satisfaction and satiety.
However, according to EFSA (European Food Safety Authority) 2009, while it has been suggested aspartame may affect appetite and fullness, there is insufficient evidence to substantiate the data. It concludes that aspartame does not affect appetite, hunger and food intake.
Those who consume a lot of these drinks may miss out on essential nutrients, micronutrients and further diminishing their nutritional status. For example: substitution of soft drinks for milk and dairy beverages can give rise to calcium and magnesium deficiency which may promote development of insulin resistance and weight gain.
Diet sodas also contain advanced glycation end products (AGEs). Advanced glycation end products (AGEs) are formed by a combination of carbohydrates, protein and fat in food when subjected to dry heat and high temperatures. AGEs in our food can lead to several diseases and accelerate aging. Several studies also suggest that dietary AGEs are involved in insulin resistance (pre-diabetes), visceral obesity (abdominal fat) and plaque formation leading to heart disease. Continuous intake of these compounds contributes to excessive accumulation into body tissues, which suppresses the immune system and resistance to diseases.
If you have genetic metabolic disorder, Phenylketonuria (PKU) or certain other health conditions, aspartame must be strictly avoided. Other concerns around regular consumption of diet sodas are its link with promoting calcium loss, osteoporosis and formation of kidney stones. However, there is insufficient evidence to draw conclusions.
Meanwhile, drinking an occasional can of diet soda is unlikely to hurt you. The artificial sweeteners and other chemicals in diet sodas are safe for most people and there is insufficient evidence that these may cause cancer. But remember diet sodas are not silver bullets for weight loss. While they may save you calories occasionally, studies suggest that regular consumption of one or more can increase your risk of obesity and diabetes For variety, try plain soda, fresh lime soda, vegetable juices, chaach/lassi, nimboo paani, skimmed milk or simply plain water with a squirt of lemon. Diet sodas are best reserved as occasional treats.