What happens to your body when you have fizzy drinks – from bloating and hunger pangs to added risk of heart disease
And how to know if you're guzzling too much diet soda
THERE’S nothing quite like the snap-crackle-pop sound of opening a can of soda and taking your first sip of the cool, fizzy liquid.
Sadly, a regular can of cola is loaded with over 10g of sugar and guzzling them down won’t be doing your health any favours.
Australian scientists recently linked ultra-processed foods (UPF) like ready meals and fizzy drinks to cancer, heart problems, type 2 diabetes and anxiety.
Further studies has also linked the sugary drinks to to heart disease and chronic liver disease, to name just a few.
It seems logical that diet fizzy drinks – where the sugar is replaced with artificial sweeteners – would be the healthier option.
But according to studies, we might not be totally dodging the health side effects of fizzy drinks by going sugar free.
The World Health Organization made a splash last year by designating aspartame – a sweetener used in Diet Coke and other sugar-free products – “possibly carcinogenic to humans”.
That’s not to say that you’ll get cancer from having a few cans of diet soda.
Gunter Kuhnle, professor of nutrition and food science at the University of Reading, told The Sun at the time: “Aspartame turns into methanol and phenylalanine in the intestinal tract.
“Methanol is converted into formaldehyde by the human body, and formaldehyde is a known carcinogen.”
The average Brit would need to glug down 15 cans of Diet Coke in a day before exceeding the limit 40 milligrams of aspartame per kilogram of body weight threshold.
Health experts are adamant that the artificial sweetener is safe to consume as long as you stick to safe daily limits.
It’s not the first time it’s been suggested that fizzy drinks aren’t entirely without risk.
Experts told The Sun how diet soda affects your body – from your teeth and stomach when you take your first gulp, to how drinking too much could put you at risk of heart disease and type 2 diabetes down the line.
HOW TOO MUCH DIET SODA CAN AFFECT YOU IN THE SHORT-TERM
From tooth erosion to bloating and sleep problems, here’s how sugar free fizzy drinks might affect your body in the short-term.
1. It leads to tooth erosion
It’s not just sugary drinks that can wreak havoc on your pearly whites.
Nyree Whitley, chief clinical officer at told The Sun: “Most people are aware of the links between sugary drinks and tooth decay, but few realise that sugar-free sodas come with their own dental risks too.
“In any food or drink it’s not just sugar content people need to be aware of, they also need to watch out for acidity levels too.
“Food and drinks with high acidity increase the chances of tooth erosion, stripping away tooth enamel and exposing the soft and sensitive inside of the tooth,” Nyree said.
This can leave you with gnashers that are more sensitive, discoloured and weak, which means they’re more prone to cracks and chips.
And tooth erosion can’t be reversed.
“Once a tooth loses its enamel it’s gone forever,” Nyree said.
“One of the biggest culprits in all sodas – regardless of their sugar content – is phosphoric acid and citric acids, also known as citrates,” she went on.
“These bond with calcium and eat away at tooth enamel.”
If you really can’t resist the occassional sugar-free drink, Nyree advised you sip it through a straw and rinse out your mouth afterwards with water or milk.
“Calcium-rich food and drink can help neutralise acids,” she explained.
You can also pop a piece of sugar-free gum to increase saliva flow, which can help neutralise acids in your mouth.
2. It can dull your taste buds
According to Llinos Connolly, Clinical Services Sister at , diet soda could affect your taste as well as your teeth.
“When sweeteners are added to foods, they produce a much sweeter taste which over stimulates the sugar receptors,” she explained.
“This overstimulation can then dull the palate for naturally sweet foods such as fruit, and can make vegetables taste even more bland and unpalatable.”
3. It can cause bloating and diarrhoea
Once a fizzy drink hits your gut, you might experience a new set of issues.
Diet sodas can often leave you feeling bloated due to their fizz, leading to gas getting trapped in your system.
But if you have a sensitive gut, the caffeine in these drinks may also leave you with diarrhoea, specialist gastroenterology dietitian Sammie Gill wrote in .
If you already have gut issues like irritable bowel syndrome (IBS), having lots of diet drinks may worsen cramping and diarrhoea as some artificial sweeteners like sorbitol, mannitol, and xylitol are known to .
4. It could lead to food cravings
Studies suggest that the artificial sweeteners in diet drinks could leave you with food cravings.
A study published to in 2021 found increased activity in the brain region responsible for food cravings and appetite in people who’d had artificially sweetened drinks, compared to those having sugary drinks or water.
According to Dr Raj Juneja, of the Face Teeth Smile Dental Clinic, hunger pangs and thirst can strike up to an hour you’ve gulped down a can of diet soda.
But published last year found that consuming sweeteners “did not conclusively induce increased food intake or change in subjective appetite ratings”.
5. You might experience sleep problems
Aside from upsetting your stomach, having large amounts diet fizzy drinks could also leave you tossing and turning at night.
This is again due to the beverages’ caffeine content.
If you drink a lot of diet soda, the amount of caffeine in your day can easily add up.
Artificial sweeteners may also have an effect too, with in mice showed that sweeteners seemed to disrupt the sleep-wake cycle.
More research would be need to confirm sweeteners’ effect on human sleep cycles.
POSSIBLE LONG-TERM EFFECTS OF DIET DRINKS
A number of studies have also delved into the possible long-term effects of guzzling too much diet soda on a regular basis.
1. They’ve been linked to heart disease and strokes
A long-running study on 80,000 women aged 50 to 79, found a link between frequently having consuming artificially sweetened drinks and an increased risk of stroke, heart disease and death.
Women consuming two or more a day 23 per cent more likely to have a stroke, 29 per cent more likely to have coronary heart disease and had a 16 per cent increased risk of death.
How much is too much?
THIS doesn't mean that you need to give up diet soda altogether.
But it’s a good idea to wean yourself off the drinks if you’re having multiple a day.
Llinos from said that if you’re having sweetened drinks every day and finding yourself craving them regularly, this could be a sign you’re addicted to them.
“Now is the time to reduce how much you consume to better your long-term health,” she advised.
“To help reduce the amount of fizzy diet drinks you have every day, set yourself ‘pop-free days’.”
“Keep a bottle of plain water within reach throughout the day, so you build new, healthier drinking habits,” Llinos added.
Victoria from BHF echoed Llinos in saying: “It’s ok to have fizzy drinks as an occasional treat but they shouldn’t be part of our daily diets.
“Sugar-free versions are usually low in calories so they’re a better choice, but make sure you’re including other drinks too.”
Some alternatives to try include:
- Fizzy water with a slice of lemon
- Sugar-free tea
- Sugar-free coffee
- Fruit or herbal tea
- Fermented drinks like kombucha
- Plain old water
Published in 2019, the study’s findings certainly sound worrying.
But Victoria Taylor, nutrition lead at the British Heart Foundation, told The Sun that they might not be as definitive as they sound.
“Since 2019, a few studies have looked at the links between artificial sweeteners and an increased risk of heart attacks or strokes,” she explained.
“Because these studies are observational, [meaning] they can’t show cause and effect, so more research is still needed to understand the potential impact on our hearts.”
Basically, this piece of research can only show a link between diet drinks and adverse health events, it can’t prove that one was the cause of the other.
It’s also possible that people who already have a higher risk of stroke or heart disease turn to diet drinks instead of sugary ones.
2. They could increase your risk of type 2 diabetes
Research has also linked artificial sweeteners found in diet fizzy drinks to an increased risk of type 2 diabetes.
Published in the last year, it found that people who consumed sweeteners were more at risk to the type 2 diabetes compared with people who didn’t.
Those who had between 16 and 18mg of artificial sweeteners per day were 69 per more likely to develop the condition than those who ate less.
Researchers wrote: “The findings strengthen evidence that these additives may not be safe sugar alternatives.”
3. They might not help you lose weight
You might assume that choosing diet drinks over sugar-laded ones would improve your waistline.
But WHO last year urged people not to have artificially-sweetened beverages if they want to shed pounds.
The health watchdog examined data from 283 studies and found that, in the short-term, sweeteners like aspartame and stevia lead to small drop in weight.
But this was only the case when people were also able to reduce the amount of calories they were consuming.
Instead, WHO said long-term consumption of the artificial ingredients could be accompanied by “undesirable effects” like an increased risk of type two diabetes, cardiovascular diseases and death.
4. They can disrupt your gut health
Liz Cooper, technical advisor at Bio-Kult, told The Sun that research on how artificial sweeteners may impact our health is still in its early stages.
“However, there is some suggestion that artificial sweeteners have the potential to alter the gut microbiome, with some studies showing a depletion of Akkermansia muciniphilia, a species of bacteria that is often associated with healthy living,” she said.
The gut expert explained that lack of this particular bacteria is associated with glucose intolerance, as one of its roles is supporting glucose metabolism, an important aspect of diabetes prevention.
“Akkermansia muciniphilia may also help to maintain gut wall integrity, and increasing evidence suggests artificial sweeteners can disrupt the balance of our gut microbiota and contribute to an increase in inflammation and damage to the intestinal lining,” Liz went on.
This condition is delightfully known as leaky gut.
Liz added: “Our gut microbiota helps to digest our food, protect our gut lining and support our immune function, whilst the integrity of the gut is vital for our overall health, as it forms a tight barrier that controls everything that gets absorbed into the bloodstream whilst blocking the passage of harmful substances.
“Therefore, an increase in inflammation and leaky gut doesn’t only affect the gut itself.
“There are numerous studies showing that poor gastrointestinal health and inflammation may play a role in the development of several common chronic diseases, both in the gut and other areas of the body.”