Drinking a can of regular Coca-Cola does not poison you, and it does not contain cocaine. What it does give you is a large dose of sugar (about 39 grams in a 355 ml can, close to ten teaspoons), a modest amount of caffeine and an acidic liquid that is hard on tooth enamel. Your body handles a single can without drama. The real concern is what happens when sugary drinks become a daily habit.
For years a dramatic list has circulated online claiming to show, minute by minute, how cola attacks the body, followed by a breakdown of "toxic" ingredients and a set of strange household tips. Some lines in it are partly true, many are exaggerated, and a few are simply invented. Below we go through the claims one by one and explain what nutrition science and food regulators actually say.
The first hour: what really happens after one can
The viral timeline splits the first hour into neat stages. Real digestion is messier, but the broad outline can be described honestly.
Ten minutes: a lot of sugar arrives at once
The sugar figure is roughly right for a standard can. The claim that you would vomit from so much sweetness if phosphoric acid did not "cancel" it has no scientific basis. Acidity makes very sweet drinks taste balanced, which is a matter of flavour, not of protecting you from nausea.
Twenty minutes: blood sugar and insulin rise
Liquid sugar is absorbed quickly, so blood glucose climbs and the pancreas releases insulin to bring it back down. The claim that "the liver converts all the sugar into fat" is wrong. Most glucose is used for energy or stored as glycogen in muscles and liver. The fructose half of table sugar is processed mainly by the liver, and when intake is high over time, part of it can be turned into fat. That long-term pattern, not a single drink, is what worries researchers.
Forty to sixty minutes: caffeine takes effect
A regular can of Coke contains roughly 34 mg of caffeine, about a third of a typical cup of brewed coffee. Caffeine does block adenosine receptors, which is why it makes you feel more alert. Effects on pupils and blood pressure from this dose are small for most healthy adults.
The "heroin" comparison
Sweet food triggers dopamine release in the brain's reward system. So do music, a hug and a good conversation. Comparing a soft drink to heroin because both involve dopamine is like comparing a candle to a forest fire because both involve flames.
After an hour: minerals and water
Caffeine is a mild diuretic, but a can of cola still leaves you with a net gain of fluid. The idea that every drop of water in the drink is flushed straight out, carrying your bone minerals with it, is not supported. The bone question is more nuanced and is covered below.
The ingredients, checked one by one
The list in the viral text describes a caffeine-free diet version and labels each additive by its E number. Here is what each one is.
- Carbonated water. Fizzy water can make some people feel bloated, but there is nothing harmful about filtered rather than spring water. Most drinks are made with treated municipal water.
- E150d (caramel colour, class IV). This brown colouring is made by heating sugar with ammonium and sulphite compounds. Its manufacture produces traces of a compound called 4-MEI, which California lists as a possible carcinogen. Regulators including the FDA, Health Canada and the European Food Safety Authority consider caramel colour safe at the levels used, which are thousands of times below the doses that caused problems in animals.
- E952 (cyclamate). An artificial sweetener 30 to 50 times sweeter than sugar, not 200 times. The US banned it in 1970 after a rat study of a cyclamate and saccharin mixture found bladder tumours. Later work, including a 24-year study in monkeys, did not show it causes cancer. It is approved in the EU and well over 100 other countries, and remains banned in the US.
- E950 (acesulfame potassium). About 200 times sweeter than sugar. It does not contain aspartic acid; that is a confusion with aspartame. It is approved in the US and EU, and there is no good evidence that it harms the heart or causes addiction.
- E951 (aspartame). Covered in its own section below because the claims about it are the most extreme.
- E338 (phosphoric acid). Gives cola its tang. Concentrated phosphoric acid is an industrial chemical, but the amount in a drink is small. Cola is roughly as acidic as lemon juice, and both can erode tooth enamel with frequent sipping.
- E330 (citric acid). The same acid found in lemons and oranges, used widely in food and medicine.
- Flavourings. The exact recipe is a trade secret, which is what the famous "secret formula" refers to.
- E211 (sodium benzoate). A common preservative, also discussed below.
Aspartame and sodium benzoate: the scariest claims
The viral text says aspartame turns into methanol and formaldehyde, causes blindness and leads to a long list of diseases from multiple sclerosis to tuberculosis. Aspartame is indeed broken down into phenylalanine, aspartic acid and a small amount of methanol, but the quantity of methanol from a can of diet soda is comparable to what you get from a glass of fruit juice. People with the rare inherited condition phenylketonuria must avoid phenylalanine, which is why products carry a warning.
In July 2023 the WHO's cancer research agency, IARC, placed aspartame in Group 2B, "possibly carcinogenic to humans", based on limited evidence. At the same time the WHO and FAO expert committee kept the acceptable daily intake at 40 mg per kilogram of body weight. A 70 kg adult would need to drink more than 9 to 14 cans of diet soda a day, every day, to exceed it. The disease list in the viral post is not supported by evidence.
Sodium benzoate has a genuine, if limited, issue: combined with vitamin C, and helped by heat and light, it can form small amounts of benzene. When the FDA tested 100 US drinks in 2006, four exceeded the drinking-water limit, and most were reformulated. A UK study in 2007 linked certain mixtures of artificial colours and sodium benzoate with hyperactive behaviour in some children, though the Food Standards Agency concluded the colours were the more likely cause. The claim that benzoate causes cirrhosis or Parkinson's disease comes from widely reported comments about laboratory cell research, reportedly in yeast, not from studies of people.
Cocaine, the "secret recipe" and other myths
Coca-Cola was created by pharmacist John Pemberton in Atlanta and first sold in May 1886. The early drink did contain cocaine from coca leaves. Fresh leaves were dropped from the formula in 1903, and by 1929 the company used a coca extract with the cocaine removed. That flavouring is still prepared under federal licence in New Jersey. A modern can contains no cocaine at all.
The household "tips" at the end of the viral list are a mix of truth and urban legend. Phosphoric acid really does help loosen rust, which is why cola can clean a corroded battery terminal or a chrome bumper, though dedicated cleaners work better. There is no traceable evidence for police officers washing blood off roads with cola, or for it being a reliable pesticide. And "it dissolves rust, so imagine your stomach" misses the point: your stomach acid is far stronger than any soft drink.
What the evidence does say about regular soft drinks
Once the myths are cleared away, a solid body of research remains, and it points in one direction.
- Weight and diabetes. Regular consumption of sugar-sweetened drinks is associated with weight gain and type 2 diabetes. Liquid calories are less filling than food, so they tend to be added on top of meals rather than replacing them.
- Teeth. Frequent sipping bathes teeth in sugar and acid. Dentists suggest drinking with meals rather than through the day, and waiting a while before brushing, because enamel is briefly softened.
- Bones. In the Framingham Osteoporosis Study (2006), women who drank three or more colas a day had hip bone density about 4% lower than women who did not. No such effect was seen in men. Researchers suspect cola may partly replace milk in the diet as well as affecting calcium balance.
- Kidney stones. A 2013 study linked soft drink consumption with a 23% higher risk of kidney stones.
The WHO advises keeping free sugars below 10% of daily energy, roughly 50 grams for an adult, with further benefits below 5%. One regular can uses up most of that allowance in a few minutes.
Practical takeaways
- An occasional cola is not dangerous for a healthy person. Daily cans add up quickly.
- If you want to cut down, try smaller cans, sparkling water with fruit, or alternating with plain water.
- Diet colas avoid the sugar and are considered safe within normal intake, but they are still acidic for teeth.
- If you have diabetes, kidney stones, bone loss or phenylketonuria, talk to a doctor about what is right for you.
- Be wary of any health post that mixes real facts with phrases like "pure poison". Accurate information rarely needs that much drama.
Sources: Wikipedia: Coca-Cola; WHO: Aspartame hazard and risk assessment (2023); US National Cancer Institute: Artificial sweeteners and cancer; Wikipedia: Cyclamate; Wikipedia: Caramel color; Wikipedia: Sodium benzoate; Wikipedia: Soft drink (health effects). The viral claim list circulated via Get Holistic Health.
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