Dextrose seems to pop up in everything.
From processed foods to flavoured water, dextrose is a familiar name on ingredients lists.
It’s also used by athletes to improve their performance.
But what is dextrose? Is it a naturally-occurring substance or something man-made? Is dextrose sugar? And is dextrose bad for you?
Read on to find out all about dextrose.
Dextrose is what’s known as a simple sugar. Chemically speaking it only has one molecule (what’s known as a monosaccharide) – meaning it’s incredibly easy for the body to break down.1
Dextrose is a starch-based sugar and is made from refined corn, rice, or wheat.
Dextrose is added to many foods, especially processed foods, to improve their taste.
Dextrose is also used by athletes for instant energy, and in healthcare settings to raise blood sugar and provide emergency hydration and energy.
Dextrose behaves the same way as pure glucose in the body.
All foods are converted to glucose by the body, some at a more rapid rate than others. Dextrose is converted rapidly into glucose (blood sugar) and has a high glycaemic index (GI) – the scale which measures how quickly a food or drink raises the levels of sugar in the blood.2
This is because dextrose only has one molecule, so there’s no chain for the body to break down. Longer chain molecules, such as proteins, take longer to be broken down by the body and as a result, don’t cause the blood sugar to spike in the way that single molecules like dextrose do.
Like all simple sugars, dextrose has a sweet taste which our brains consider ‘rewarding’. This makes us seek out its pleasant taste and eat more than we otherwise might – a phenomenon which has been compared to addiction.3
You’ll see dextrose on the ingredients list of many different processed foods. Being intensely sweet in flavour, dextrose gives a pleasant taste and palatability to plain foods and cheaper ingredients. This helps explain the rise of dextrose in commercial food production.
It is also added to many savoury foods to help disguise high salt content, as the sweetness of the dextrose balances out a salty flavour.
Cultured dextrose is a type of preservative which inhibits the growth of mould and yeast in food products, extending their shelf life.
Cultured dextrose was formerly known as preservative 280 (propionic acid) and is a by-product of sugar or milk fermentation alongside probiotic bacteria.4
As it’s so readily absorbed by the body, dextrose is able to provide rapid energy to patients without them needing to eat or drink. This is useful in intensive care settings, where it’s often used intravenously (IV) as part of partial or total parenteral nutrition.5
Dextrose is also used in gels, tablets or injections to raise blood sugar in cases – such as with people with diabetes – where it has dropped dangerously low. Many people with diabetes or hypoglycaemia (very low blood sugar) carry dextrose tablets to take by mouth to combat low blood sugar.
Dextrose is used in sports drinks, dextrose tablets and hydration and energy gels. Dextrose is energy-dense, and thanks to its ability to enter the bloodstream quickly, it can help replenish glycogen stores. This is especially important for endurance and long-distance athletes such as cyclists, marathon runners or triathletes. 6
When used by an athlete after strenuous exercise, or by a medical professional in a clinical setting, dextrose can be highly beneficial – even life-saving. It helps stabilise very low blood sugar and can provide vital energy in an instant.
When it comes to your diet, however, regular consumption of too much added dextrose can have adverse effects.
Dextrose is a simple sugar, and it’s well-known that consuming too many simple sugars is bad for the health.
The body stores excess sugar as fat, which can lead to obesity. Obesity comes with various health risks such increased prevalence of some diseases, and the onset of type II diabetes.9
Getting too much of a simple sugar like dextrose gives you an initial rush of energy which wears off quickly, leaving you tired and lethargic later. This is one reason why people tend to over-eat sugary foods, as they find themselves needing more sugar as a ‘pick-me-up’, without realising the sugar is sapping their energy.10
Eating too many dextrose-enriched foods can also affect your mood negatively. Excessive sugar intake has been linked with depressive symptoms in several studies.11
Consuming too many foods containing simple sugars is known to increase our desire to eat sugary foods, whilst reducing the level of satisfaction we get from the same amount of sugary food over time.
This can lead to overeating and is a risk factor for obesity.12
This is when the body’s cells stop responding to the hormone insulin. In a healthy body, insulin helps escort glucose into cells to be used and stored as fuel, but eating too much simple sugar can interfere with this process.
Insulin resistance is a key factor in developing type II diabetes.13
Dextrose has the same number of calories as table sugar – 4 calories per gram.14 Remember, dextrose is chemically the same as glucose, or blood sugar, so it’s not considered any healthier or better for you.
Dextrose is found naturally in some foods including:7
Dextrose is added by the manufacturers to a large range of processed foods, including:
There’s a tendency to label things ‘natural’ if they are derived from plants.
However, it’s important to remember that a substance can be natural, but it can still be harmful to our health.
Dextrose is made from refined starch – which comes from plants like corn or wheat. Dextrose also occurs naturally in some foods such as honey.
The dextrose which is found in so many processed foods and beverages has been refined using an industrial process into a fine white crystalline dextrose powder, before being added in unnatural amounts to our foods to enhance their flavour and palatability. This is why, for example, a strawberry flavoured yoghurt is many times sweeter than a real strawberry.
In this respect, dextrose adds an artificial level of sweetness to things we eat, so it’s unnatural to eat so much dextrose in our diets, although dextrose is not unnatural itself.
What’s the difference between dextrose and glucose?
There isn’t a real difference between the two sugars, which is why the terms are often used interchangeably. As previously mentioned, dextrose and glucose are chemically identical and behave the same way in the body.
The subtle difference between them is:8
In terms of where it sits on the sweetness scale, dextrose is less sweet than sucrose, fructose and glucose, but sweeter than lactose and maltose.
Supplementing with dextrose could potentially give your exercise performance a real boost.
One study from 2006 found that supplementing with dextrose drinks after every practice session for eight weeks improved the performance among the participants, a group of 31 female college rowers.15 Dextrose emerged superior to the other type of sugar used in the study, ribose.
Because dextrose takes such a short time to be converted to energy by the body, you’ll get an energy boost as soon as you’ve consumed dextrose. Dextrose is also calorie-dense, which is why it’s used by bodybuilders and those looking to gain weight during their training.
Usually, we’re taught to avoid simple sugars which have this instant energising effect in favour of complex carbohydrates, like whole grains and vegetables, which offer a slower release of energy. But when you’re running a marathon or powering through a 90-minute gym session, you need something a little more rapid.
This is why dextrose supplementation is useful for athletes and those participating in endurance sports. Glycogen stores (the body’s energy reserves) become depleted during exercise, and dextrose can quickly restore them, helping you work out harder and for longer.16
Dextrose can be taken in tablet form, as well as in sports drinks, gels and as powder added to protein shakes or water.
You can take dextrose either during training, or directly after a session.
Dextrose is safe to eat in small amounts in food. The NHS recommends we consume no more than 30g added sugar a day, so keep an eye on quantities of dextrose in food.17
A dose of around 50g is recommended as a workout supplement. Most dextrose tablets are around 50g.
If using dextrose in the management of diabetes, hypoglycaemia or another medical condition, speak to your GP.
Consuming too much dextrose can lead to:18
Last updated: 10 May 2021
Joined Holland & Barrett: Apr 2019
Masters Degree in Toxicology and BSc Hons in Medical Biochemistry
Bhupesh started his career as a Clinical Toxicologist for Public Health England, advising healthcare professionals all around the country on how to manage clinical cases of adverse exposure to supplements, pharmaceuticals, cosmetics, industrial chemicals and agricultural products.
After 7 years in this role and a further year working as a drug safety officer in the pharmaceutical industry, Bhupesh joined Holland & Barrett as a Senior Regulatory Affairs Associate in 2019.