is diet coke better than regular coke

Is Diet Coke Better Than Regular Coke in 2023?

By Danny Webber
Danny Webber is a SENr registered practitioner, an ISAK certified Anthropometrist and a UK Anti-Doping accredited adviser.
| Updated on July 26, 2023

Can diet coke be useful for weight loss, or do the health risks out-way the benefits?

Diet drinks that are loaded with low-calorie sweeteners (LCS) are thought to be just as bad as their sugary alternatives i.e. “full-fat” coke. (I still don’t get that term) as it’s pure sugar, not fat.

But the question is, is there any evidence to support this, and what exactly does the research say about the effects diet coke and LCS (aspartame) have on health and weight management?

Because it’s low in calories, can diet coke be used to support weight loss? So, is diet coke better than regular coke?

What is Diet Coke?

Diet Coke is a low-calorie and sugar-free cold beverage alternative to regular Coca-Cola (coke). Unlike regular coke which contains table sugar, diet coke contains artificial sweeteners like aspartame and cyclamates to sweeten them.

Is Diet Coke Bad for You?

Is coke bad for you

Drinking one or two glasses of diet coke isn’t likely to hurt you. Since diet coke is sugar-free, we could assume that it could aid in weight loss but studies are mixed. The effects of diet coke on weight loss are conflicting.

Studies show that artificial sweeteners like aspartame and cyclamates are associated with an increased risk of obesity and metabolic conditions and may increase appetite, however, this is only likely to result from very large intakes of such artificial sweeteners, close to 6 cans of diet coke a day.

Health Benefits of Diet Soda

While not much extensive research is made on the benefits of diet coke, it has been shown to improve fatty liver and decrease some detrimental effects that regular coke has.

Aspartame and Leukemia: What Does Science Say?

Aspartame has been linked to causing cancer, increasing weight, and many other health issues. However, science doesn’t support this to be the case in humans.

In 2006 the US National Cancer Institute conducted a study of nearly half a million people, comparing those who consumed drinks containing aspartame with those who did not and found aspartame did not increase the risk of leukemia, lymphoma, or brain cancer

Why Regular Soda is So Bad for You

Regular soda and coke are linked with obesity, kidney problems, and cancer. Coke and soda contain a lot of sugar which is consuming may lead to weight gain, diabetes, and cardiovascular diseases. Regular consumption may also lead to elevated blood pressure.

The Problem with Sugar

Sugary drinks like regular coke and soda significantly increase the consumption of added sugars which are linked with obesity, weight gain, heart diseases, metabolic disorders, etc.

What’s the Difference between Diet and Regular Soda?

difference between diet coke

Regular soda contains a lot of sugar that contributes to obesity, weight gain, diabetes, cardiovascular diseases, and many more. Whereas, diet soda contains artificial sweeteners instead of traditional sugar and has no calories accomplishing a similar taste.

Diet Soda is Just as Bad as Regular Soda

Regular soda contains a lot of sugar whereas diet coke contains artificial sweeteners like aspartame.

Despite being low or zero calories, diet coke offers no nutritional value whatsoever.

Diet Coke is not a healthy drink but if it helps you to reduce your calorie intake by simply switching from regular coke to diet coke, then it can support weight loss.

Diet Soda and Kidney Health

In a research study, doctors reported that drinking sugar-free cola beverages might have effects on kidney health.

Kidney functions seem to tail off when people drank several cans of diet soda a day.

These studies show that over the time of 20 years, kidney functionality had decreased by more than 30% than that of those who didn’t.

The link between diet coke and kidney functionality persisted even when looking into other factors of health problems. This research was conducted on the Nurse’s Health Study.

Diet Coke Linked to Premature Birth and Childhood Obesity

While a can or two of diet coke isn’t going to hurt you in the long term, excessive consumption of diet coke while pregnant has been linked to some negative outcomes which were associated with an 11% higher risk of premature birth.

Is Diet Soda More Dangerous Than Sugar-Sweetened Beverages?

While one or two cans of both diet coke and regular coke are not likely to harm you in any way, high consumption of both diet coke and regular coke is linked with higher risks of heart disease and other health problems.

Is Diet Coke Better Than Regular Coke for Weight Loss?

Firstly, to lose weight, you need to be in a calorie deficit, meaning you need to consume less energy than what you expend. For long-term success, you need to do this consistently.

Immediately, the thought of swapping a 500ml bottle of Coke (200kcal; 50g sugar) for a 500ml bottle of calories in Diet Coke (4kcal; 0g sugar) is much more appealing to help reduce calories, and prevent consuming 50g of refined sugar. But what about the huge amounts of aspartame?!

Rogers et al 2016 conducted a meta-analysis that showed the consumption of LCS improved weight loss in adults and children when compared to sugar-based alternatives, as part of an ad libitum diet

Another meta-analysis in 2014 found no association between LCS and body weight or fat mass and may have a positive association with BMI.

The authors concluded that “data from RCTs, which provide the highest quality of evidence for examining the potentially causal effects of LCS intake, indicate that substituting LCS options for their regular-calorie versions results in a modest weight loss and maybe a useful dietary tool to improve compliance with weight loss or weight maintenance plans.” 

Is Diet Coke Better Than Regular Coke

More recently, Higgins et al 2018 in an RCT compared the effects of three daily aspartame doses (0, 350mg, or 1050mg) for 12 weeks, to assess the effects each dose has on glycaemic control, appetite, and weight management

Let’s be clear on this…350mg of aspartame is the equivalent of drinking 2 x 330ml cans of diet coke. So 1050mg equals 6 cans!!

The study showed that drinking 0, 2, or 6 (330ml) cans of diet coke per day for 12 weeks have no effects on glucose and insulin levels, appetite, and ratings of hunger or body weight. HbA1c (a marker of blood glucose levels), total cholesterol, HDL, LDL, and liver function were also no different between trials.

Healthy Alternatives to Coke

While switching from coke and soda might seem impossible, here are some healthy alternatives to soda drinks:

  • Plain Water
  • Iced Tea or Coffee
  • Lemonade
  • Kombucha
  • Coconut Water
  • Juiced Vegetables
  • Green Tea/Coffee
  • Sparkling Water, Sugar-Free Cordial.

Also Learn about: Is Caffeine a Diuretic?

Take-Home Message: Diet Coke vs Regular Coke

Just to put this into perspective, this doesn’t make diet coke/soda a miracle cure for losing weight.

There’s still absolutely no nutritional value in diet coke nutrition and therefore it is not recommended to start drinking 6 cans of diet coke per day.

However, drinking the occasional can now and again will not cause cancer or diabetes, but it can support weight loss.

– Drink water as much as possible throughout the day, but the odd can of coke will not harm you.

– If you like fizzy drinks but are trying to lose weight, swapping to diet versions can support weight loss.



What happens if you drink Diet Coke every day?

It depends on how much you drink. Research shows that you need to consume a lot of diet drinks to cause any health issues from artificial sweeteners, so one can a day will not do much harm. People who drink a lot of Diet Coke are advised to drink less as this replaces healthier options and may reduce nutrient intake opportunities.

Is diet coke addictive?

There is no conclusive evidence to suggest that Diet Coke is addictive. People who regularly consume it have built these habits into their lifestyle, but stopping this is not the same as stopping smoking or drugs.

What does Diet Coke do to the stomach?

Besides feelings of bloating and general discomfort from overconsumption, it is currently unknown the extent of (any) damage caused by Diet Coke, of which a very large intake would be needed. The majority of studies showing any negative health effects are done in rodents, not humans.

Can you drink diet coke on the keto diet?

Yes because it is sugar-free.

What are health issues related to diet coke?

The artificial sweetener content present in diet coke is linked to cancer, weight gain, high blood pressure, and brain tumors, however, this has only been shown in rodent studies, not in humans.

Does aspartame affect your heart?

There is some evidence to suggest that women who drink two or more diet drinks a day are at greater risk of stroke, coronary heart disease, and all-cause mortality.

Do low-calorie sweeteners affect your heart?

There is some evidence to suggest that women who drink two or more diet drinks a day are at greater risk of stroke, coronary heart disease, and all-cause mortality.

What can I drink instead of Diet Coke?

Water is the best thing everybody can drink. However, a sugar-free cordial is also an acceptable alternative.

Should diabetic people drink diet coke?

Infrequent small amounts of Diet Coke should be ok for diabetics. However, large intakes are not recommended. This area requires more research, but any diabetic should look to avoid any food or drink that may cause disturbances to their sugar regulation and weight loss strategy

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