You’ve probably heard at least once that “diet sodas are even worse than regular.” But sometimes, those kinds of headlines can be sensational and over-generalized. Today, let’s look specifically at one diet soda, Diet Dr Pepper, and try to determine: Is it healthy?
Diet Dr Pepper contains the artificial sweetener aspartame, which studies have linked to increased risk of cancer, heart disease, obesity, and other issues. It also has caramel color and sodium benzoate, which have both been linked to potential carcinogens, and phosphoric acid, which may contribute to osteoporosis and tooth decay.
Below, I’ll dig into all these ingredients in Diet Dr Pepper and the research on whether they’re healthy. I’ll discuss whether Diet Dr Pepper is a good choice for weight loss, whether it raises blood-sugar levels, and more!
Is Diet Dr Pepper Good for You?
Here are the eight specific questions I’ll be answering about Diet Dr Pepper nutrition. Click any of them to skip ahead to that section—or just keep scrolling to read them all:
- What Is Diet Dr Pepper Made Of?
- What Is the Sweetener in Diet Dr Pepper?
- Can Diet Dr Pepper Raise Blood Sugar?
- Does Diet Dr Pepper Have Caffeine?
- Is Diet Dr Pepper High in Sodium?
- Is the Sodium Benzoate in Diet Dr Pepper Harmful?
- Is Diet Dr Pepper Good for Weight Loss?
- Is It Bad to Drink Diet Dr Pepper Everyday?
- Is Diet Dr Pepper Vegan?
1. What Is Diet Dr Pepper Made Of?
Let’s start by looking at what Diet Dr Pepper actually contains. There are a few different versions, including Diet Cherry Vanilla and Diet Caffeine Free. But most of the ingredients are the same.
So let’s look at the standard Diet Dr Pepper, as of November 2021:
Diet Dr Pepper Ingredients: Carbonated Water, Caramel Color, Aspartame, Phosphoric Acid, Natural And Artificial Flavors, Sodium Benzoate (Preservative), Caffeine.
Here are my takeaway points on Diet Dr Pepper’s ingredients:
- Diet Dr Pepper contains aspartame. This may be the artificial sweetener with the worst reputation of all. Personally, I mostly avoid it because of the research suggesting a connection to depression. But there are also possible links to cancer, heart disease, and more. We’ll cover aspartame in more depth below.
- Diet Dr Pepper contains caramel color. This coloring ingredient can potentially contain a carcinogen called 4-MeI. In a Consumer Reports study, many sodas with caramel color tested at surprisingly high levels for 4-MeI.
- Diet Dr Pepper has sodium benzoate. This food preservative is a bit controversial because it can potentially turn into benzene, which is a carcinogen. That said, it’s unclear how likely this is in Diet Dr Pepper. This ingredient is actually used to make fireworks, too—it’s part of what makes the whistling sound. Read more on sodium benzoate below.
- Diet Dr Pepper has phosphoric acid. As a food ingredient, this particular acid has been linked to osteoporosis and lower bone density, as well as cavities and tooth decay. So, not great.
- Diet Cherry Vanilla Dr Pepper has red 40. This dye isn’t in the normal Diet Dr Pepper, but it’s in the Cherry Vanilla one. This synthetic dye is controversial for causing possible hyperactivity in children, and for possible connections to cancer. More on red 40 here.
As you can see, there are plenty of potential negatives to Diet Dr Pepper from a nutrition standpoint. That said, the biggest concern for most people will likely be the sweetener, aspartame. So let’s look closely at that ingredient next.
2. What Is the Sweetener in Diet Dr Pepper?
Diet Dr Pepper is sweetened with the artificial sweetener aspartame. Aspartame is the most widely used artificial sweetener in the world, and one of the most controversial for its possible health effects. These include possible links to cancer, heart disease, obesity, stroke, Alzheimer’s, depression, and more.
It would be difficult to cover everything about aspartame’s possible health risks here. If you want to go deep on this subject, start with this page from U.S. Right to Know. That said, I’ll try to summarize here.
Some of the biggest concerns with aspartame include:
- Cancer: There has been a considerable amount of evidence showing that rodents develop cancer when exposed to aspartame over their lifetimes. Aspartame was also posed as a possible explanation for dramatic increases in malignant brain tumors in the years immediately after its approval.
- Heart Disease: Several high-profile cardiologists have sworn off aspartame based on the evidence. A 2014 study found that women who had more than two diet drinks per day experienced more cardiovascular events (like heart attacks).
- Brain Disease: Studies show that consumption of diet drinks is linked to three times higher risk of stroke and dementia. There are also possible connections to Alzheimer’s disease, via methanol, which is a breakdown product of aspartame in the body.
- Obesity: This one is quite ironic, as aspartame is often used in “diet” products. But research shows connections between aspartame and weight gain, along with increased appetite.
- And more: There have been possible links found between aspartame and headaches, mood disorders, learning problems, kidney function decline, diabetes, pre-term birth, and more. Find a more complete list with sources here.
Although aspartame is still legal and FDA approved, for me personally, I’m shocked at the amount of allegations against this chemical.
For me, the “risk vs reward” of consuming aspartame is not good. If the research is correct, then you’re risking cancer, heart disease, migraines, kidney decline, depression, and more… Just to drink an artificial sweetener?
Simply put, I think it’s worth avoiding aspartame—even if it’s not completely proven to be harmful. Find a healthier zero-calorie sweetener like erythritol or monk fruit extract. Or just gradually adjust your taste buds to not crave as much sweetness.
- Does Diet Dr Pepper Have Sucralose? Diet Dr Pepper does not contain sucralose. Instead, it is sweetened with aspartame.
- Does Diet Dr Pepper Have Fake Sugar? Diet Dr Pepper is sweetened with aspartame, which is about 200 times sweeter than normal sugar. Therefore, much less can be used, and it is essentially a zero-calorie ingredient at the quantities used in soda.
3. Can Diet Dr Pepper Raise Blood Sugar?
I wasn’t able to find any research directly on whether Diet Dr Pepper raises blood sugar. However, Diet Dr Pepper contains aspartame, which may affect insulin resistance. (source)
Specifically, aspartame and other artificial non-caloric sweeteners seem to alter your gut bacteria. This can affect your tolerance to carbs on an ongoing basis.
A 2014 study on rats found that “aspartame elevated fasting glucose levels and an insulin tolerance test showed aspartame to impair insulin-stimulated glucose disposal.”
I also found some discussions of artificial sweeteners causing insulin issues through another mechanism. That is, the sweet taste of aspartame may trigger an insulin response even without real sugar in your bloodstream.
So, proceed with caution. If blood-sugar control is crucial for you, I’d recommend testing whether Diet Dr Pepper has any affect for you. I’d also recommend maybe just not having it often, as that may lead to more eventual issues (via changes in gut bacteria).
4. Does Diet Dr Pepper Have Caffeine?
Diet Dr Pepper and Diet Cherry Vanilla Dr Pepper contain caffeine. However, if you want a caffeine free version, just look for Caffeine Free Diet Dr Pepper. It has the same taste without the stimulating caffeine to keep you awake.
5. Is Diet Dr Pepper High in Sodium?
Diet Dr Pepper has about 100mg of sodium per 20 oz bottle. This is only about 4% of the daily recommended limit of 2,300 mg of sodium per day.
Of course, if you drink Diet Dr Pepper all day, you could end up consuming at least several hundred milligrams of sodium from it. So be mindful if you’re trying to keep your sodium levels in check.
Here is a table showing the sodium content of several diet Dr Pepper drinks. As you can see, they’re all the same in this regard:
|Dr Pepper Product||Sodium (per 20 fl oz)|
|Diet Dr Pepper||100mg|
|Diet Cherry Vanilla Dr Pepper||100mg|
|Caffeine Free Diet Dr Pepper||100mg|
|Dr Pepper Zero Sugar||100mg|
For comparison, 100mg is about the same amount of sodium as in a handful of Planters Cocktail Peanuts.
6. Is the Sodium Benzoate in Diet Dr Pepper Harmful?
Sodium benzoate is only present in small amounts in any food. It’s limited by the FDA to make up only 0.1% of the weight of the foods it’s added to. Still, there are some health concerns.
The biggest concern is that sodium benzoate is able to convert to benzene, a known carcinogen, in certain conditions. This has particularly been a concern in soft drinks where sodium benzoate is also present with ascorbic acid. (source)
(Side note: Diet Dr Pepper does not have ascorbic acid as an ingredient. So theoretically, there should not be any benzene in Diet Dr Pepper.)
There was a study in 2005-07 showing that 10 out of 200 soft drinks tested contained more than the allowable levels of benzene (5 parts per billion). Since then, those products have been reformulated to comply with allowable levels. But the study also showed ~60% of soft drinks had some measurable level of benzene.
The FDA has stated that the levels of benzene in soft drinks are not a risk. (source)
There have been some other concerning studies on the impacts of sodium benzoate in animals. It may raise levels of inflammation, oxidative stress, or even risk for ADHD (source). Some people also have allergic reactions to it.
The Environmental Working Group has assigned sodium benzoate a risk score of “1 to 3” on a scale of 1 to 10 (with 10 being the worst). So the overall risk is low.
Personally, after reading into all of this, I’m not that worried about the safety of sodium benzoate. But I’d still rather not consume it daily.
7. Is Diet Dr Pepper Good for Weight Loss?
One of the reasons people choose zero-calorie drinks like Diet Dr Pepper is to avoid extra calories. But the evidence shows that consuming artificial sweeteners is surprisingly ineffective for weight loss. And they may even lead to weight gain.
You’d expect that switching from sugar to zero-calorie sweeteners would cause significant weight-loss… After all, you’re cutting all those calories that you used to drink from sugar, right? But in most studies, they cause little to no weight loss.
Here’s one explanation: Artificial sweeteners keep you accustomed to sweet drinks and food. So you still get cravings for sweets, and you end up eating more calories from something else.
Other explanations have to do with your microbiome—that is, your gut bacteria. In any case, Diet Dr Pepper (and other drinks with aspartame) may not be the best for weight loss.
But remember: The key to weight loss is your overall diet and calorie balance. One food doesn’t make or break your diet. So if your goal is weight loss, consider tracking your calories, or follow some of these 18 tips for weight loss without counting calories.
Whether you drink Diet Dr Pepper will not make or break your weight-loss journey by itself. But it may be a negative, based on the research connecting aspartame with weight gain.
8. Is It Bad to Drink Diet Dr Pepper Everyday?
Personally, I wouldn’t feel comfortable drinking Diet Dr Pepper every day. Why? The main reason is aspartame.
The research into aspartame and depression was what initially convinced me to avoid the ingredient. But there are many possible issues, detailed above.
I would personally only have Diet Dr Pepper as an occasional treat.
9. Is Diet Dr Pepper Vegan?
Diet Dr Pepper is generally considered vegan. It is possible for the caramel color or natural flavors to be sourced from animal-derived ingredients, but it is not likely.
It’s also possible that someone would say Diet Dr Pepper isn’t vegan is due to animal testing. That’s because the artificial sweetener used in Diet Dr Pepper (aspartame) has been tested on animals extensively.
That said, boycotting drinks like Diet Dr Pepper today can’t undo the animal testing that was already done. So most vegans are okay with consuming these artificial sweeteners.
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