Sugared Soft Drinks: Health Risk? (and What About Diet Soda?)

Sodas in 2-liter bottles

Sodas in 2-liter bottles

When I was a child, one of the greatest treats in our small world was to go to the five-and-dime (a store where many items used to be that price, kids! Example, Woolworths) which had a soda fountain, a long bar serving concoctions like sodas and milkshakes. One of my favorites was a cherry coke — soda water mixed with Coca-Cola and cherry syrup. Serving size for this very sweet drink was probably about 8 oz., or 250 ml. The combination of sweet and carbonation was out of that world! (In other words, a taste combination that stimulated evolved preferences for sweet but far beyond what was usually available in the diet we evolved with.)

Now, of course, sweetened sodas are available everywhere, and sold in much larger serving sizes. My brother was addicted to 7-11 Big Gulps — a massive 30 oz. soda for drinking on the go. Cane sugar was replaced by cheaper HFCS (High Fructose Corn Syrup) as corn was subsidized and sugar controlled at an artificially high price by agribusiness lobbying of Congress. Hamburger fast-food chains built an empire on burgers, fries (potatoes, also a high-glycemic-index food), and soft drinks.

There is evidence that high-carbohydrate diets in general, and sugar in particular, are the cause of the great increase in obesity. Even natural fruit juice and concoctions served in coffee bars have more sugar in one quickly-absorbed dose than is wise.

Politicians have attempted to reduce overconsumption of sweetened soft drinks by limiting serving sizes or proposing special taxes. Most people find these efforts intrusive and they haven’t gotten very far in the political system; like many pleasures, soft drinks don’t cause problems consumed in moderate serving sizes and only on occasion. Trying to force people to change their habits by law or regulation is unlikely to be very effective; widespread public understanding of the problem does seem to be working, however, as soft drink consumption is down and obesity seems to be leveling off in the US though still increasing elsewhere.

Scientists are still studying the effects of sugar on the body, and a recent study reviewed in Science Daily shows another downside of sugary drinks and the large blood sugar spikes they cause:

Research to be presented at the Annual Meeting of the Society for the Study of Ingestive Behavior (SSIB) finds that daily consumption of beverages sweetened with high-fructose corn syrup or sucrose can impair the ability to learn and remember information, particularly when consumption occurs during adolescence.

Both adult and adolescent rats were given daily access to sugar-sweetened beverages that mirror sugar concentrations found in common soft drinks. Adult rats that consumed the sugar-sweetened beverages for one month performed normally in tests of cognitive function; however, when consumption occurred during adolescence the rats were impaired in tests of learning and memory capability.

The lead author, Dr. Scott Kanoski from the University of Southern California, says, “It’s no secret that refined carbohydrates, particularly when consumed in soft drinks and other beverages, can lead to metabolic disturbances. However, our findings reveal that consuming sugar-sweetened drinks is also interfering with our brain’s ability to function normally and remember critical information about our environment, at least when consumed in excess before adulthood.”

In addition to causing memory impairment, adolescent sugar-sweetened beverage consumption also produced inflammation in the hippocampus, an area of the brain that controls many learning and memory functions.

Which confirms another hazard of frequent consumption of highly-sweetened soft drinks: a period of poor learning ability after each serving. Which is likely to give ammunition to schools that ban them in lunchrooms or vending machines.

But what about diet drinks sweetened with the usual artificial sweeteners like aspartame or sucralose? One concern has been that these drinks set off the body’s insulin release because they trigger sweet receptors just as sugar does, but the insulin causes more harm since it has nothing to work on — the body has been tricked. This theory has been used to support the idea that diet soft drinks will increase cravings for sweets and cause other problems that make avoiding them wise. But the evidence of this is very thin, one recent study showed no ill-effects, and I personally enjoy occasional diet soft drinks without problems. Most likely diet soft drinks in moderation cause few problems for those who aren’t sensitive to the specific sweeteners used.

Note that many sodas — and fruit juices like orange juice — are highly acidic and can erode tooth enamel over time. In other words, if you drink Diet Coke all day long, your tooth surfaces will quickly be decalcified and start to deteriorate. This is another good reason to avoid frequent consumption of these drinks.

For more on diet and weight loss:

Getting to Less Than 10% Body Fat Like the Models – Ask Me How!
Starbucks, Jamba Juice Make You Fat
Fat Doesn’t Make You Fat. Government Guidelines Did!
‘Fed Up’ Asks, Are All Calories Equal?
Fructose: The True Villain?
More on “Fed Up”, Sugar Subsidies, and Obesity
Another Study on Diet Drinks
LeBron James Cut Carbs for Lean Look
Why We’re Fat: In-Depth Studies Under Way
Almonds: Superfood, Eat Them Daily for Heart Health
Fish Oil Supplements Ward Off Dementia
More on Diet Drinks: Best Studies Show They Aid Weight Loss
Vani Hari: “Food Babe” and Quack
Cleanses and Detox Diets: Quackery
Gluten-Free Diets: The Nocebo Effect
Acidic Soft Drinks and Sodas: Demineralization Damages Teeth
Fish and Fish Oil for Better Brain Health
Salt: New Research Says Too Little May Be Unhealthy
Bulletproof Coffee: Coffee, Oil, and Butter for Breakfast?