All About Diet Sodas

Diet soda is back in the news, after a recent study claimed that it causes more weight gain than regular soda. But if you were to take a closer look at all the facts, you’d find that there are many other types of diet soda besides diet. The bottom line is that you should drink diet soda because it’s not a weight-loss option. It’s not really a “diet” per se, since it still contains calories. But if you’re trying to lose weight, it’s the wrong choice. Why? Because while the fiber is supposed to curb your appetite, the truth is that this drink provides little to no fiber, and it contains high fructose corn syrup, which can cause a lot of problems in the body, including

Diet soda is marketed as a tasty and healthy alternative to sugary soda pop. But are diet sodas, which are artificially sweetened, really just a healthier alternative to regular soda? Not exactly. In fact, many diet sodas are quite high in calories. And although diet soda can be a healthy choice for occasional consumption, it’s not a good choice for a regular part of your diet.

Diet sodas are undeniable. We drink it to avoid the caloric sugar of regular soda, right? But do the benefits of fewer sugar calories outweigh the risks of using artificial ingredients?

What is a diet drink?

Good old 1952. Television makes its debut in Canada and the first light soft drink is sold. It was a ginger ale called a no-calorie drink. The first Diet Coke came on the market seven years later. These drinks are sweetened with saccharin (think Sweet ‘N’ Low) and are intended for diabetics, not for people who limit sugar and count calories.

How times have changed.

The development of diet drinks has long been of interest to food manufacturers and consumers because the sugar in traditional soft drinks is high in calories, lacks nutritional value and increases the risk of tooth decay. Since sugary soft drinks provide such a large portion of the calories in the American diet, one would theoretically think that replacing this sugar with a calorie-free sweetener would lead to significant changes in weight and health. You’ve changed: Since the introduction of calorie-free sweeteners, weight has increased and health may have deteriorated.

Why are light soft drinks so important?


Consumption of light soft drinks was stable in the 1990s, but began to increase in 2002, from 4.8 ounces per person per day to 5.6 ounces in 2004. (The person who lives down the street and drinks a Big Gulp every morning on their way to work skews these numbers for the rest of us.) 86% of Americans use diet foods, including low-calorie, low-sugar and sugar-free foods and drinks. In the United States, consumers spend about $21 billion a year on these beverages. By comparison, those same consumers spend only $14 billion on organic food.

What you should know about diet drinks

Have you ever heard of diet coke? So do I. Let’s break down the ingredients. It contains carbonated water, caramel, aspartame, phosphoric acid, potassium benzoate, natural flavors, citric acid and caffeine. We’ll take them one by one.

Carbonated water

It’s water dissolved by carbon dioxide. Poof, we got carbon dioxide. While it’s not very beneficial to your health (it’s actually part of the breathing process that your body is trying to get rid of carbon dioxide), it’s great for removing coffee stains.

Caramel colour

Without them, Coke wouldn’t be brown and happy hour beer wouldn’t be gold. Caramel is the most widely used ingredient in the world for food colouring. There is no taste, only color. It is made by heating carbohydrates (such as fructose, dextrose, or invert sugar) with a food acid (such as sulfuric, phosphoric, or citric acid) to break the bonds between the sugars. Carbohydrates can also be heated with salts (e.g. ammonium, sodium and bicarbonate). Polyglycerol esters of fatty acids are also used as antifoaming agents in the production of caramel dye. Think of caramel as the color of burnt sugar. As might be expected (since it is used in diet drinks), caramel is soluble in water.

Negative health effects of caramel color are unlikely, provided a person does not consume more than 200 mg/kg body weight. However, there is a chance of an allergic reaction, but this is true of many food ingredients. Caramel contains very few calories and most calories are not absorbed in the gastrointestinal tract. If you want to know what life would be like without the caramel color in Diet Coke, send a time machine back to the early 1990s and meet Crystal Pepsi.



Aspartame, an artificial sweetener consisting of aspartic acid, phenylalanine and methyl ester, is a chemical, not a natural compound. It was discovered in 1965 by a chemist named G.D. Searle. (For more on the discovery of artificial sweeteners, see our research report on Splenda). In fact, at that time he was looking for a cure for an ulcer. After 16 years, aspartame received limited approval and in 1983 its use was allowed in diet drinks. It is the most popular sweetener in the US food industry (as of 2007). Aspartame is approved in more than 90 countries, its use is widespread. Trade names for aspartame are Equal, NutraSweet and Tri-Sweet.

Aspartame has 200 times the sweetness of regular sugar. Since it still has 4 calories per gram (just like table sugar), you can use much less of that intense sweetness in diet drinks. In North America, aspartame is mainly consumed in light soft drinks. The acceptable daily intake (ADI) is 50 mg/kg in the United States and 40 mg/kg in Europe and Canada. For an 80 kg person, this equates to 3,200 to 4,000 mg per day. The following table shows the aspartame content of typical foods.

Product category Portion size Aspartame content
Non-alcoholic soft drinks 12 ounces 180 mg
Gelatin dessert 4 ounces 95 mg
Soft drinks in powder form 8 us 120 mg
Hot Chocolate 6 oz. 50 mg
Pudding 4 ounces 25 mg
Frozen novelty 2 – 3 ounces 50 mg
Fruit drink (10% juice) 6 oz. 70 mg
Peppermints 1 coin 1,5 mg
Vitamins 1 Vitamin 4 mg
Ice cream 4 ounces 50 mg
Yoghurt 8 us 124 mg
Chewing Gum 1 bar 6-8 mg

Source: NutraSweet Company

Before we look at this chart and try to figure out how someone can consume enough aspartame to cause health problems: a study of eating disorder patients found that they consumed up to forty diet drinks (300 ml each), 30 pieces of sugar-free chewing gum, and up to 350 packets of artificial sweetener per week.

After consuming a sip of light soda, aspartame enters our small intestine where it is broken down into its components: Aspartic acid, phenylalanine and methanol. These substances can then enter the bloodstream. Phenylalanine can accumulate in the blood, but it is difficult to predict the response to high doses of phenylalanine because experimental animal models regulate metabolism differently.

The methanol is then metabolized to formaldehyde and formic acid. But before you call the poison control center, remember that methanol is also found in figs and orange juice (among other foods) and that formaldehyde comes from scary things like apples, carrots and coffee. I hope you’ve opened some kids’ eyes to this one. Acidosis can occur when there is a significant amount of formic acid in the blood.

Animal tests show that aspartame can cause cancer and brain damage, with the dose tested being about the same as the ADI for humans. Studies in humans show that consumption of 2-100 mg/kg aspartame has no effect on cognition or behavior.

In 2007 and 2008, scientists confirmed and reinforced the multiple potential of aspartame to cause cancer at doses approaching those suggested for humans. Additionally, if exposure begins while the fetus is still being carried, the risk of developing cancer increases. However, no reliable epidemiological studies have been conducted.

In 2007, the journal Critical Reviews of Toxicology published a 98-page report on aspartame (shortly before the above study was published). The study shows that the more aspartame we consume, the more likely it is to affect our health. Nevertheless, the authors concluded that there is no reliable relationship between aspartame consumption (in the amount assumed in one’s diet) and nervous system and behavioral disorders. Moreover, there seems to be generally little evidence that it can cause cancers and starvation reactions.

Aspartame has 92 FDA listed side effects and is not recommended for pregnant women or young children. Hmmm, if it’s not safe enough for the pregnant mother on the street, is it safe enough for everyone else?

Phosphoric acid


This substance has a sour and acidic taste and inhibits the growth of fungi and bacteria. It differs somewhat from direct phosphorus in that it binds with magnesium and calcium in the digestive tract, forming salts that are not absorbed. This can lead to a reduction in the amount of material needed for bone attachment. As you might expect, studies have linked phosphoric acid consumption to decreased bone density. However, other studies have shown that phosphoric acid has no effect on calcium excretion.

Diet Cokes, which generally contain phosphoric acid (colas do not), have also been linked to kidney disease and kidney stones. In one study, two or more colas per day more than doubled the incidence of kidney disease; this association was not observed with other colas. Phosphoric acid has little to do with our health, but it is very effective at removing rust from iron and steel tools.

Potassium benzoate

This substance is a preservative and inhibits the growth of yeast, fungi and bacteria. It has minimal taste and low toxicity risk. Unfortunately, potassium benzoate can form benzene with ascorbic acid (vitamin C). Benzene is a known carcinogen. Sodium benzoate is also used in some diet drinks, but because most people don’t need the extra sodium, manufacturers are using it less and less. Although potassium benzoate does not do much for our health, it is excellent for making pyrotechnic whistles in fireworks.

Natural flavourings

The magical natural aroma was once the saskra root in Diet Coke, but this plant has disappeared. In other words, natural flavors can contain countless elements. I received the following statement from Coca-Cola after inquiring about the natural flavors used:

Thank you for contacting the Coca-Cola Company, sir. Andrews. Thank you for your interest in Diet Coke.

As you may know, flavor formulas are very valuable confidential information, which is why we do not discuss flavor blends used in Coca-Cola branded products. However, consumers can be confident that all flavorings used in The Coca-Cola Company brands have been approved as safe and appropriate for use by local regulatory authorities in the countries where they are sold.

In addition, the FDA regulates what substances may be labeled as flavorings, whether natural or artificial, and we strictly adhere to all of these guidelines. If you would like to learn more about the FDA’s flavor standards, you can reach them at or by calling 1-888-INFO FDA.

We hope you find this information useful. If you have any further questions or comments, please do not hesitate to contact us again.


Industry-consumer relations
The Coca-Cola Company

Citric acid


More than half of citric acid is produced in China. It acts as a preservative and gives a sour taste. Too much of it can damage tooth enamel. Although it is naturally present in citrus fruits, most food grade citric acids are not derived from them. To produce it, cultures of an organism called Aspergillus niger feed on a sugar medium. Aspergillus is a fungus that grows on starchy food crops.

Despite diet sodas being less in calories, they often do a similar amount of harm to teeth when it comes to decay. Dr. Shokraee at Vallance Dental Centre informed us that it’s the acid in these drinks that does most of the damage, which is still present in many diet alternatives. If you must drink caffeinated drinks, be sure to keep up with your dental appointments and take good care of your teeth in-between visits. Of course, it’s better to go without wherever possible but we understand that life is made of choices and easier said than done.

Although citric acid does not contribute much to our health, it is an excellent additive in bathroom cleaners.


Caffeine is the most widely consumed stimulant in the world and is found naturally in several plants, including coffee beans, kola nuts, tea leaves and cocoa beans. (See our article All About Caffeine, available to members of the PN community). Caffeine is a methylxanthine. Other common methylxanthines are theobromine and theophylline, which are found in cocoa and tea. Methylxanthines act as adenosine receptor blockers and phosphodiesterase inhibitors. If you have no idea what I just said, here’s another explanation. Adenosine acts as a brake in the central nervous system. Therefore, when its action is blocked (by caffeine), stimulation occurs.

Caffeine is actually one of the most studied and effective ergogenic acids on the planet. However, its purpose in diet drinks is likely to be immediate stimulation, and it is potentially addictive.

Does light soda really help you stay slim and healthy?

People who tend to overeat seem to consume more artificial sweeteners and diet drinks. This may reflect the ability of artificial sweeteners to stimulate overeating, perhaps by increasing appetite and/or disrupting the ingested associations between sweetness and caloric content of food. Remember, we get used to sweet tastes. Diet sodas provide an extremely sweet sensation that can interfere with enjoying unprocessed/naturally sweet foods. Some experts suggest that dietary factors may exacerbate the link between sweetness and calories, contributing to overeating and weight gain.

Can aspartame help control the glycemic response? The results are mixed. A study of patients with type 2 diabetes showed that a breakfast with aspartame (true translation: 2 Diet Cokes from 7 to 11) caused a similar rise in glucose and insulin levels. Other studies show that it can help control blood sugar levels.

There is also a link between the consumption of diet drinks and the development of metabolic syndrome. This is just one association, and other factors may come into play (including endless X-Box sessions and Tastycake rants). In particular, it is not a direct causal link. The problem may be that those who consume more light soda have an unhealthy lifestyle.

So what are the alternatives to diet soda? Consumption of sugar from regular soft drinks can create an environment in the body that leads to more stored fat. Sugar can also weaken the immune system by lowering white blood cell counts, and has been linked to yeast overgrowth and hyperactivity.

Summary and recommendations


If I told you to go to the store and pick the three healthiest drinks, would light soda be among them? Instead of thinking about how a certain product or drink can harm our health, I prefer to think about how a certain product or drink can improve our health. If you are thinking about diet drinks in this context, it may help to get clarity. Although it has not been proven that light soft drinks are deadly to your health, we know that regular consumption of light soft drinks does little to improve your health. From a health perspective, light soda is probably not the best idea.

When it comes to consuming diet drinks, the following thoughts come to mind:

  • Can the body tolerate concentrated amounts of phosphoric and citric acids? (Hint: that’s not what it looks like)
  • Does the body know how to deal with concentrated amounts of artificial sweeteners such as aspartame or sucralose? (Hint: that’s not what it looks like)
  • If someone stops drinking diet soda, what do they eat instead? And how will this affect their health and well-being?

I have seen diet drinks help people control their weight and improve their health. But I’ve also seen diet drinks prevent people from controlling their weight and worsen their health. Given the data showing a link between light soda and health risks, is it worth the risk? Only you have the last word.

Also consider the budget factor. What are we wasting our money on when we buy diet soda? We don’t have quality food. You’re not getting any calories. I’d rather someone save their money for a weekly 12 pack and stock up on quality food and tea.

If you’re into sports, bodybuilding or fitness and your biggest mistake is drinking light soda a few times a week, you probably don’t need to worry. Nutritional support, right? However, if you are overweight, have an unhealthy lifestyle and are addicted to diet drinks, this can be one of the many vices that ruin your health. Then it was time to pick the most pressing issue.

Other interesting information about diet drinks

Drinking soda depletes your water supply. To produce 1 liter of soda, you need about 2.5 liters of water.

The ADI is defined as the dose to which individuals in a subgroup can be exposed on a daily basis throughout their lives without appreciable health risk. The ADI for acesulfame-K is 15 mg/kg/day (also found in some diet drinks). The ADI for sucralose (Splenda) is 5 mg/kg/day.

One hypothesis is that the pancreas receives a signal to release insulin when it senses a sweet taste in the mouth. (New research also shows that taste buds are also present in the gastrointestinal tract, which may explain the body’s reaction to certain tastes.) If the sweetness is obtained artificially with aspartame, the extra insulin produced by the pancreas is not available and hypoglycemia occurs.

Drinking soft drinks before testing body fat with an underwater scale can cause serious errors in the results.

Someone who drinks only 2 cans of soda a day will have to spend $206 in a year to keep up this habit. If there is more than one soft drink drinker in the family, the annual volume can quickly double (or even triple). The bad news is that Diet Coke is not tax deductible. The good news is that there are many non-profits out there.

If you follow a kosher or vegan diet, you can safely eat fudge. (However, Coca-Cola recently released a kosher version of regular Coke for Passover, in which the fructose-rich corn syrup was replaced with regular sugar.)

Frequently Asked Questions


Why diet soda is bad for you?

The artificial sweeteners in diet soda can cause a spike in blood sugar levels, which can lead to insulin resistance and weight gain. Diet soda is also linked to an increased risk of heart disease, stroke, and type 2 diabetes.

Why is diet soda worse for you than regular soda?

Diet soda is often loaded with artificial sweeteners, which can cause a spike in blood sugar levels. This can lead to insulin resistance and weight gain.

Which diet soda is the healthiest?

The healthiest diet soda is water.