Does diet soda support weight loss?When trying to lose weight, you’ll inevitably need to make some dietary adjustments, such as eliminating empty calories from your meals. That means avoiding any food and drink that's mostly made up of sugar or fat, as these goodies offer no nutritional value. And one of the most popular empty calorie beverages you’ll want to skip? Carbonated beverages, such as Pepsi and Coke products.

For many of us, soda is a tasty treat that’s hard to give up. So when trying to lose weight, it’s tempting to just replace your favorite soda with its diet counterpart. Instead of sugar, diet sodas are sweetened with artificial sweeteners like aspartame, cyclamate, saccharin, acesulfame-k or sucralose.

But what does the research say? Is it really worth switching regular soda for diet?

Exploring the Research

During the last few years, news outlets have reported on studies finding that drinking diet soda is associated with weight gain. Specifically, several observational studies have found that using artificial sweeteners and drinking high amounts of diet soda is associated with an increased risk of obesity and metabolic syndrome (a cluster of conditions that increase the risk of heart disease, stroke, and diabetes). And in one study in particular, participants who started out at a normal weight but drank three diet sodas a day were twice as likely to be overweight or obese eight years later as their non-diet-soda drinking peers.

The question is, why?

Reasons for the Findings

It’s important to remember, especially in an observational study, that correlation does not equal causation. So some skeptics are asking if there are additional factors to consider that could explain these sorts of findings.

More research is needed (and is ongoing) to determine the true health impacts of diet soda. In the meantime, researchers have developed several theories that could explain why drinking diet soda could be linked weight gain in some cases:

  1. Diet soda won’t “fix” a person’s health overall. It’s possible that some of the people who drink diet soda regularly are unhealthy in general. This could mean they’re overweight; their diets are poor; they lead sedentary lifestyles; and/or they’re predisposed to developing heart issues and other chronic illnesses. Simply drinking diet soda would not improve a patient’s health overall.
  2. Diet soda affects insulin production. Insulin is used by the body in the process of storing sugar. And when we taste anything sweet, even artificial sweeteners, our brains automatically tell our body to begin producing insulin. But if there's no sugar for that insulin to process, the metabolic process could be disrupted. Some researchers also think this may explain why several studies have shown a link between regularly drinking diet soda and metabolic syndrome, a collection of symptoms that includes larger waist circumference, higher blood pressure, and higher blood sugar.
  3. Diet soda makes us crave sweets. You’ve likely heard about how our taste buds naturally crave sweet things. Evolutionarily speaking, this traces back to our primate roots, when the sweetest things in our diets were fruit. These days, however, sugary snacks are manufactured on a massive scale. Sugar is also often added into items both for taste and to extend the shelf life of our food. Now here comes diet soda - a sweet drink that, while sugar-free, can actually trigger additional sugar cravings. As a result, drinking a diet soda may trick you into overeating sugar later in the day.
  4. Diet soda tricks you into eating more. A final possibility is that diet soda can trick the brain into thinking you’re doing a better job dieting than you really are. Sure, you’ve given up the 140 calories in a normal soda can - but that doesn’t mean you can replace that 140 calories with something else. Unfortunately, it’s easy for people to do just that, especially when dealing with diet-related sugar cravings.

What You Should Do

At this time, these theories for why diet soda may negatively affect weight loss are just that: theories. And while observational studies link diet soda with obesity, it’s not clear whether diet soda is a cause of this.

What does this mean for you? It’s worth considering this information as you decide on your dietary adjustments. Switching from regular soda to diet is certainly a good change if you’re just starting out. Over time, however, consider swapping some of your diet sodas for unsweetened tea or plain old water. It just may be the healthy swap you need to make!

Struggling to lose weight? Still not sure about what sorts of dietary changes you need to make? Schedule an appointment to meet with our team! Right Weight Center is an affordable, physician-directed medical weight loss program. We provide straightforward weight loss solutions that help people achieve their weight loss goals via a custom, tailored health plan. Our team includes board-certified family care physicians, physician assistants, and technicians - all of whom understand the challenges of losing weight and maintaining weight loss. With our custom plans and tools - including Lipotropic injections and natural, proven metabolism boosters - our team can help you stay focused and achieve your weight loss goals, easily and safely.

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