Do Artificial Sweeteners Cause Weight Gain?

Artificial sweeteners, do they cause weight gain? Are they really good for you? This article details artificial sweeteners and other sugar substitutes and possible weight gain.

Artificial Sweeteners do they cause weight gain
Artificial Sweeteners – well known brands

Artificial sweeteners exist in many forms, but they all share the same virtue.

They provide maximum sweetness without overloading the body with calories. In fact, some artificial sweeteners provide no calories at all.

The fact that they are low to zero-calorie sugar alternatives has always made options like saccharin very popular with people who are trying to lose weight.

However, certain evidence suggests artificial sweeteners may actually cause weight gain instead of supporting weight loss.

In this article, I’m going to take a closer look at the different types of artificial sweeteners.

I will look at what they can do, and how the allegations they may work against you rather than with you when you are trying to lose weight.

I will also look at some of the safety concerns about their use.

What are Artificial Sweeteners?

Artificial sweeteners are substances that provide sweetness without presenting all the calories that sugars do. They are chemicals that are synthesized in labs.

Artificial sweeteners are used in thousands of products and you may be surprised where they turn up. You can find them in certain soft drinks, cakes, desserts, and some brands of chewing gum. They are also used in some ready meals and even in toothpaste.

There are two main types of artificial sweetener:

  • Bulk Sweeteners
  • Intense Sweeteners

Before going any further it’s important to point out the fact that normal sugar has other characteristics apart from sweetness. These physical properties contribute to the sensory and structural quality of food.

Manufacturers use bulk sweeteners when these characteristics need to be maintained.

Bulk Sweeteners

Bulk sweeteners are mostly sugar alcohols such as mannitol and sorbitol. They are generally used as sugar substitutes in foods and confectionery.

Sweeteners of this nature generally provide around 2.4 calories per gram.

This is a lot lower than common sugar, which provides around 4 calories per gram.

However, when more than 10% of a product is bulk sweetener, manufacturers have to place a warning on the label. This is because, at this level, bulk sweeteners may cause gastrointestinal problems for anyone who has a sensitive stomach.

Intense Sweeteners

Intense Sweeteners are many time sweeter than bulk sweeteners.  For example, aspartame, saccharin, and Acesulfame K can be up to 200 times sweeter than table sugar.

Sucralose and Neotame are more newly-approved intense sweeteners that are sweeter still.

Sucralose is the key ingredient in Splenda and it can be 400-7000 times sweeter than sugar.

Depending on how it’s used, Neotame may be 8,000 – 13,000 times sweeter than sugar.

You can find Intense sweeteners in certain beverages and dairy products. They may also be used in confectionery that only requires help with sweetness but not texture.

When used in soft drinks, intense sweeteners, like aspartame, can help produce a specific taste. They may also feel slightly different from sugar while they are in the mouth.

One of the big differences between aspartame and Sucralose is the aspartame gets digested, while Sucralose does not.

Some Popular Types of Artificial Sweetener

Acesulfame K

Also called Ace K, this is a zero-calorie sugar substitute that given the E number E950 in Europe. Its often marketed under the brand names Sweet One and Sunett.

Acesulfame K is a white crystalline powder. More specifically, it’s the potassium salt of 6-methyl-1,2,3-oxathiazine-4(3H)-one 2,2-dioxide.

There’s nothing very natural about the compound at all. Many people point out the effects of acesulfame potassium has not been adequately studied. The European Food Safety Authority dismiss these claims. As does the FDA.


In Europe, Aspartame is codified as E951. It’s a methyl ester of the aspartic acid/phenylalanine dipeptide. It’s been around since the 1960s and there are many charges made against it.

Aspartame is one of the artificial sweeteners that is said to cause weight gain. It’s also one of the most rigorously tested food additives.

In 2018, after a thorough evaluation, the EFSA came to the conclusion it’s safe for human consumption (at current levels of exposure).

Aspartame is only four calories per gram.


Saccharin is the granddaddy of artificial sweeteners. It was first synthesized in 1879 by a chemist experimenting with coal tar derivatives.

Although it’s got no calories, saccharin never really caught on until the sugar became short during the First World War.


Sorbitol (E420) is a sugar alcohol that can be made by chemically reducing glucose. More often than not, the process starts with corn syrup.

However, sorbitol is also naturally occurring in prunes, apples, pears, and many other plant-based sources.

The body metabolizes sorbitol slowly and it’s only 2.6 calories per gram. You can find it in many diet-friendly foods such as low-calorie soft drinks and ice creams.

Unfortunately, sorbitol is also a laxative that may cause some people to feel gastrointestinal distress.


Sucralose (E955) is the compound that results from the chlorination of sucrose.

It remains stable when heated and is, therefore, suitable for use while baking. There are no calories in Sucralose and it’s kind to the teeth.

Some studies on animals indicate Sucralose may reduce levels of probiotic bacteria living in the gut. There are also other worries about its effects on the health, but the FDA classes it as safe.

The acceptable safe daily intake is no more than 15 mg per kg of body weight per day.

Artificial Sweeteners weight gain
Artificial Sweeteners instead of sugar

Why Artificial Sweeteners are Often used in Place of Sugar

Obesity is a big problem, all over the world. It endangers the health of the afflicted and puts a huge burden on the healthcare services.

Because of their low-calorie nature, artificial sweeteners offer obvious value in the war against obesity.

Additionally, sugar replacements can also help prevent tooth decay and keep blood sugar levels under control.

Dietitians also point out how useful they can be for diabetics who want to enjoy sweet foods without their blood sugar levels spiraling out of control.

Artificial Sweeteners May Increase Hunger
hungry woman

Artificial Sweeteners May Increase Hunger

No, you haven’t read it wrong.

Some evidence suggests these low-calorie sugar substitutes may increase hunger.

Animal-based research suggests artificial sweeteners can increase appetite and make you eat more.

More worryingly, research involving humans suggests it too.

According to a comprehensive study, published in Cell Metabolism in 2016, these artificial sugar substitutes may affect the area of the brain that regulates appetite.

The scientific team responsible for this discovery consisted of researchers from the University of Sydney’s Charles Perkins Center and the Garvan Institute of Medical Research.

The team believes this is due to the way such sweeteners affect the brain’s reward centers, where sweetness and energy content are normally perceived together.

Increasing Appetite

According to lead researcher Associate Professor Greg Neely (University of Sydney’s Faculty of Science), when the combination of sweetness and energy value is not within normal parameters, it forces the brain to re-calibrate. It does this by increasing appetite to try and elevate blood sugar levels.

The researchers also discovered artificial sweeteners may encourage hyperactivity, cause insomnia, and reduce sleep quality. These are all symptoms that are consistent with a state of mild starvation.

So, how bad is the hunger likely to be?

For the purposes of one part of the study, the researchers gave fruit flies food with artificial sweeteners in it. They did this for more than five days.

When the fruit flies were subsequently given food containing natural sweeteners, their calorie intake increased by 30%. [SOURCE]

This is not the only study that suggests artificial sweeteners may cause you to gain weight. However, it’s important to be aware there are also studies that suggest the opposite.

More than anything else, the research available at the present time indicates a need for further study.

Safety Concerns

Causing weight gain is just one of many allegations made about artificial sweeteners. Throughout the years there have been numerous claims these sugar alternatives may be unsafe.

Using saccharin as an example. Back in the 1960s saccharin was a big thing. Despite the bitter aftertaste, many people used saccharin tablets to sweeten their coffee and tea.

Saccharin continued to popular during the 1970s as well. However, due to concerns it may be hazardous to the health, there was a warning on the bottle.

In 1981, sales of saccharin were banned. This remained the case for nearly 30 years. Then, in 2010, the powers that be did an about-face and declared it safe. [SOURCE]

The use of artificial sweeteners of all kinds continues to be a controversial subject. Some experts argue it’s impossible to predict how these chemicals may affect the body after many years of use.

Even Stevia sometimes gets bad press. It’s not even an artificial sweetener. It’s a natural low-calorie sweetener taken from the leaves of the plant Stevia rebaudiana.

Are Artificial Sweeteners a Good Idea?

It’s a free world and each individual has the right to decide for themselves whether or not to consume artificial sweeteners. However, avoiding them entirely is always going to be hard. They turn up in the most unexpected places.

As for their ability to cause weight gain, that requires further study. As does their ability to help with weight loss. 

When used as a sugar substitute as part of a low-calorie diet they will almost certainly be a good way to reduce overall calorie intake.

Their potential to cause weight gain by increasing appetite is something users can monitor for.

If an artificial sweetener does exhibit this effect, that’s a good time to stop.

The thing is, artificial sweeteners are just that—artificial. There is nothing natural about them. They are chemical-based. The experts who worry the long-term effects are unknown could have a point.

With this in mind, Stevia may be a better option. It’s taken from the leaves of a plant and is 100% natural.

In Summary – Takeaways

No matter what route you choose to go, if you are considering using a low-calorie sugar substitute, you are likely doing so through a desire to lose weight.

Although the value of artificial sweeteners is still a subject of debate, one thing is clear.

The first area you need to be looking at is your diet. It’ needs to be healthy, nutritious, and low in calories.

Get that right first. Look at artificial sweeteners and other sugar substitutes later.

It’s also worth remembering, food does not have to be sweet. It’s just something people become accustomed to.

It is possible to remove sugar from the diet without using any form of substitute. After a while, the taste buds adapt to the lack of sweetness.

In fact, if you cut out sweet-tasting food for a month or two and then try a sweet treat you used to enjoy you may find it unbearably sickly. 

It may sound strange, but that’s just the way the cookie crumbles. Try it and see.

About Steve Calvert

Steve Calvert (CPD Certified in Nutrition for Weight Loss) Steve is an experienced writer and researcher with a wealth of knowledge and expertise in the fitness, nutrition and weight loss sector. He has a background in bodybuilding and the martial arts and continues to use a combination of exercise and healthy eating to stay in shape. Steve has reviewed hundreds of supplements since 2012. He is very accurate and methodical in his approach and understand the importance using correctly dosed ingredients. LinkedIn

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