Can You Drink Coke or Diet Coke During Pregnancy? Is It Safe?

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Written by Gina Wagg BA, Dip.

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Whether it’s the classic Coca-Cola or its caffeine-heavy diet version, the Diet Coke, chances are you probably enjoy popping open a cold one now and then.

If you’re pregnant, though, you have to be a bit more careful about what you’re eating and drinking. And you may be wondering if Coca-Cola and Diet Cokes are on the safe list or not. 

Drinking the occasional Coca-Cola while pregnant is generally safe, but moderation is essential. Cokes have a lot of sugar, as well as caffeine – both of which should be monitored during pregnancy. Also, some studies show a correlation between Diet Coke and overweight babies, so you might want to avoid or moderate your intake.

In the rest of this article, we’ll look more closely at some of the risks involved with drinking too many Cokes while you’re pregnant and why Diet Cokes might not be as healthy for you as you think. Keep reading to find out more.

This article is part of our larger, more in-depth article on soda during pregnancy. If you want to learn more soda safety, and its potential effect on your baby and you, then check out the article here.

Coke or Diet Coke and Pregnancy: Is It Safe To Drink?

When it comes to Cokes, Diet Cokes, and pregnancy, most expectant moms are usually concerned with caffeine and whether or not it’s safe. 

Current recommendations are for pregnant women to keep their intake of caffeine limit below 200 mg (.007 ounces) per day (source: The American College of Obstetricians and Gynecologists).

Since a single can of Coca-Cola or Diet Coke falls well below that level (32 and 42 mg respectively), both soft drinks are within the acceptable range for caffeine intake while pregnant (source: Coca-Cola). 

Unfortunately, caffeine isn’t the only consideration for drinking Coke products. The two soft drinks are also full of sugar and/or artificial sweeteners, and are classed as sugar-sweetened beverages.

For example, one 12-ounce (355 ml) original Coca-Cola Classic contains 39 grams (1.37 ounces) of sugar. Diet Coke has no sugar but contains artificial sweeteners, which vary in their safety (sources: Coca-Cola & Diet Coke).

Human studies show that many people who drink Diet Coke (and other diet drinks made with artificial sweeteners) often gain more weight than those who drink regular, sugar-sweetened Coke and caffeinated sodas (source: Harvard Health Publishing). 

pouring coke into a glass with ice

Although the explanation for why this happens isn’t entirely clear, there are some theories. These include the following:

  • Diet Coke has no calories. Some experts believe that people may actually consume more calories from other sources – a little like saying “I’m doing great by drinking diet sodas, so I can eat ice cream tonight” – whilst unknowingly consuming many more calories!
  • Artificial sweeteners are much “sweeter” in taste and more potent than natural sugars. Therefore, people who frequently drink Diet Coke may get used to the overpowering sweetness of the drink and no longer enjoy less sweet foods like naturally sweetened fruits and vegetables, turning to more sugary, fatty snacks instead.
  • Diet drinks may increase the desire for sweet foods. The more cravings for sweets you have, the harder they are to deny.

So what does all of that mean?

It means – and studies back this up – that people who heavily consume zero-calorie caffeinated drinks like Diet Coke may actually gain more weight than people who drink regular Coca-Cola. Too much weight gain during pregnancy can be unhealthy for both mother and child (source: Harvard Health Publishing). 

Plus, as I mentioned above, Diet Coke has more amounts of caffeine than regular Coke (though both remain significantly below the 200 mg (.007 ounces) daily allowance for pregnant women).

Ultimately, drinking Coke is OK during pregnancy, but only in moderation.

What About Caffeine Free Coke? (e.g., Coke Zero?)

Like regular Coke, Caffeine Free Coke is relatively safe when consumed in moderation. You don’t have to worry about caffeine with these sugary drinks, but they still have plenty of sugar and carbs. And contrary to popular belief, Coke Zero is not caffeine-free. It’s only sugar- and calorie-free.

If you’re trying to avoid caffeine consumption while pregnant, Caffeine Free Coca-Cola is an option, but the added sugars and empty calories still aren’t great for you. If you’re going to forego caffeine, you may also want to take a look at our many other suggestions for safe pregnancy drinks.

Coke Zero, though, is not caffeine-free. It has no sugars and no calories and is more like a Diet Coke than a Caffeine Free Coke. The difference is the flavor, with Coke Zero tasting more like the original Coca-Cola Classic. It still contains 34 grams (1.19 ounces) of caffeine, though (source: Healthline). 

There is a Caffeine Free Coke Zero option, which is caffeine-free, but both it and the original Coke Zero use artificial sweeteners, and we’ve already talked about how those aren’t great for you in the above section. 

a bottle of coke zero on a table

How Much Coke Should I Have When Pregnant? 

There’s no hard and fast rule on how much Coke you can have while you’re pregnant. However, limiting yourself to a single can a day is usually a good option. After all, you want to avoid caffeine and sugar as much as possible. Plus, most of your calories should come from healthy foods, where possible.

During their third trimester, women can increase their caloric intake the most, and even then, most expectant moms shouldn’t be consuming more than 2,400 calories a day (source: Medline Plus). 

Original Coca-Cola products have 140 calories per can. If you have just two cans of Coke a day, that’s more than 10% of your daily allotment of calories – which is a lot, considering there are many other alternatives when you’re pregnant.

What Does it Mean if I’m Craving Coke?

Despite rumors that Coke cravings are a sign of calcium deficiency, these cravings likely mean little more than that you want something sweet, bubbly, and with a bit of caffeine in it. Scientists haven’t found any secret or compelling meaning behind Coke cravings.

Can Coke Help With Pregnancy Nausea?

Drinking Coke can sometimes help with pregnancy nausea, although there’s little science out there to explain why it helps. Carbonation often sits easier on an upset stomach than plain water, but beyond that, there’s no concrete explanation of why drinking Coke can help with nausea.

In an interview with the Wall Street Journal, gastroenterologist Dr. Lawrence Szarka says that carbonated drinks can lessen stomach acidity, which helps get rid of nausea. He also explains that Coke contains phosphoric acid, which is used in OTC anti-nausea drugs (source: Wall Street Journal). 

For more on “fizzy” drinks during pregnancy, read our article here.

Can Coke Affect a Pregnancy Test or Create a Fake Result?

Coca-Cola will not give you a fake result on a pregnancy test unless the test itself is defective. Pregnancy tests measure the level of human chorionic gonadotropin (hCG) present in urine to determine whether someone is pregnant, and that isn’t present in Cokes.

Youtube user RP Enterprises tried this out and posted the results on Youtube:

As you can see, the results of the test were negative. 

I, too, tried this test for myself using a New Choice pregnancy test from Dollar Tree and received an identical negative result. 

However, you shouldn’t drink too much Coke, water, or any other liquid before taking a pregnancy test, as overly diluted urine could give you erroneous results.

Can Drinking Coke Prevent Pregnancy?

Coke cannot prevent pregnancy, so you shouldn’t rely on it to help keep you from getting pregnant. The only surefire way to ensure you don’t get pregnant is to abstain from sexual activity. Condoms, birth control, and IUDs are other reliable, though not 100% effective, options.

Unfortunately for many couples trying unsuccessfully to have a child, human studies do show that drinking one or more Cokes consistently every day can lower fertility rates, so you may want to cut back on them if you’re having trouble conceiving (source: Boston University).

However, other than that, Coke can’t prevent pregnancy. There seems to be misinformation on the internet claiming that you can use Coke as a spermicide. This is false; you cannot use Coke to prevent pregnancy.

This myth is so prevalent that it made it onto; where it has its own page (source: Snopes). 

a woman drinking a refreshing coke

Hopefully, this article has told you everything you need to know about Cokes and pregnancy. As with everything you eat or drink while pregnant, moderation is the key. 

If you want to know more about how soda and sugar-sweetened beverages can affect you and your baby, read our more in-depth article on soda when pregnant.