That drinking can make you overeat does sound a bit odd. We have one stomach, after all, and filling it with a caloric drink should reduce the amount we eat -- the drink takes its stomach share and supplies calories, right?
But that's not the way it is, and accumulating evidence shows that our body has a hard time registering calories from beverages in the tally towards satiety.
When women were served water, diet soda, regular soda, orange juice, milk or no drink with lunch, those drinking caloric beverages consumed about 100 additional calories for that meal. In another study researchers proved that solid candy is better for your waist than soda: when they gave men and women 450 calories a day of either soda or jellybeans for a month, candy eaters ate less food, compensating for the extra calories, while soda drinkers did not, so they ate more calories than usual. Another study looking at the effects of food form (solid, semi-solid or liquid) on appetite, fed participants either a whole apple, applesauce or apple juice of equivalent caloric value. The apple juice reduced hunger the least, the whole apple reduced hunger the most and the applesauce response was intermediate -- people who had apple juice where ready for their next meal almost an hour earlier than those that had a bitable apple.
The more you drink the hungrier you get
Not only do drink calories go uncounted, some studies also show that when you drink calories you may add not just the calories of the drink, but even some extra food.
A new study in the American Journal of Clinical Nutrition looked at what 13,704 people drank over 24 hours, and what and how much these people ate.
The correlation was straightforward: people reporting higher caloric intake from sugary drinks also consumed more calories from food. They also tended to eat foods with higher caloric density, and eat more saturated fat, sugar and salt. This study also showed that the more calories people drank, the more snacking they did, and the longer their snacking episodes got.
This study further demonstrates that calories that you drink aren't well compensated for: the people in this study who drank an average of 1000 calories a day ate an additional average of 22oo calories, bringing their total daily caloric intake to 1100 higher than people on the lower range of sugary drink intake - and 350 of these extra calories came from extra food.
Drinking and eating: a vicious cycle
This is a correlation. It seems like people who drink more calories (mostly from added sugars) eat more, and eat less healthfully, but does that mean that drinking leads to eating? This study can't prove that. Maybe bad habits just cluster.
The authors speculate that while drinking more calories might lead to eating more food and eating poorly, it's also possible that each bad habit begets the other -- drinking soda leads to eating a lot, and eating calorically dense foods leads to drinking more soda - a vicious cycle feeding itself.
Watching what you drink can break that cycle, and that's why all reasonable weight loss and healthy nutrition advice emphasize elimination or reduction of sugary drinks. Getting rid of the sugary drink's calories is the first bonus, but for many people changing the sugary drink habit holds the promise of other positive eating behavior changes that can follow, much more easily.
Full disclosure: I'm vice president of product development for Herbal Water, where we make organic herb-infused waters that have zero calories and no sugar or artificial ingredients. I'm also a pediatrician and have been promoting good nutrition and healthy lifestyle for many years.
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