Good Sugar And Bad Sugar

We’re all aware that sugary foods are bad for our health, but what causes confusion frequently among dieters are questions such as “don’t fruits and vegetables also have sugar? And aren’t these meant to be good for you?”.

As weight management specialists here at Plato Weight Management who have helped hundreds of dieters achieve their ideal body weights over the last several years through our highly sought after weight management program, this is a topic that we address a lot more than you would think.

In this blog post, I’ll discuss:

  • Natural sugar and refined (added) sugar
  • Glucose, fructose and sucrose
  • Sugar and weight loss
  • Sugar and inflammation
  • Natural Sugar and inflammation
  • How to reduce inflammation
  • Long-term health problems

Natural sugar and refined (added) sugar

To talk about sugar, we first need to talk about the two different types of sugar: natural sugar and refined (added) sugar.

Foods with natural sugar don’t just contain sugar but also large amounts of essential nutrients that are helpful while dieting, such as fibre, minerals and vitamins.

Natural sugar is the good sugar because the essential nutrients provided in the foods containing natural sugar help keep blood sugar down, slow down the absorption of sugar, reduce cholesterol levels, and increase the feeling of being full.

Natural sugar is primarily found in unprocessed foods like milk, fruits, vegetables, cheese, and grains.

refined and natural sugar

In contrast to natural sugars, which have additional components like fibre and micronutrients, refined sugars have no other nutrients, which is why they are known as “empty calories” and, subsequently, bad sugar.

They come from sugar cane or sugar beets which are processed to extract the sugar. Refined sugar is mainly found in processed foods, including ice cream, candy, and soda, alongside the less thought of ketchup, yoghurt, and bread.

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Glucose, fructose and sucrose

Sugar, whether natural or refined, can be broken down into glucose, fructose and sucrose.

Both types of sugar contain these three types; only their percentages vary between processed and unprocessed foods.

sugar fizzy drink

It is the fructose that we need to be concerned about when it comes to our health. Although sources of natural sugar like fruit also contains fructose, the amount is minor and the levels of fructose needed to provide detrimental health consequences are quite high and would be highly unlikely to reach from fruit alone.

Refined sugars like from processed foods, on the other hand, have quite high levels of fructose.

For example, an apple which, as noted, is a natural sugar source, has about 13 grams of fructose in comparison with a 330 ml can of fizzy drink, which is a refined sugar source, has about 40 grams of fructose. This means that an apple has around three times less fructose than a can of fizzy drink.

Additionally, because fruit has a lot less sugar, it means your body has a lot more time to use the sugar as fuel before storing it as fat. 

Sugar and weight loss

Sugary foods have been recommended to be kept to no more than one-tenth of your total caloric intake per day by the Dietary Guidelines For Americans.

What’s problematic with added sugar is how the body processes it.

Sugar is a simple carb that the body easily converts to glucose. When glucose enters your blood, your blood sugar quickly rises and to restore a normal glucose level, the pancreas secretes insulin, which reduces blood sugar levels by transporting glucose from the blood into the body’s cells for use as energy.

sugar and weight loss

The issue arises when the glucose is delivered into your blood too frequently when your body doesn’t require it. Because of the heightened glucose supply, your pancreas goes full throttle, releasing even more insulin to compensate.

This excessive insulin shifts glucose into the fat, muscle and liver cells, where it’s stored as glycogen (the storage form of carbohydrate) to be used as energy when at a later period.

Unfortunately, we have limited storage for glycogen, and subsequently, when this occurs, the extra glucose is converted to fat to be stored. Fat cells can produce chemicals that lead to inflammation which we will expand on a bit later.

Another negative consequence of added sugar is that consumption is one of the main factors contributing to craving fatty foods later in the day. Sugar triggers reward centres neurologically and increase the release of the feel-good hormones serotonin and endorphins.

This over the top sugary intake leads to excessive calories, which accumulate over time to result in weight gain.

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Interestingly, another contributor to cravings for glucose could be our gut microbiota, meaning the bacteria, viruses, and fungi in our gut. Although the research in this area is still emerging, these gut bacteria are essential to our digestive health. Refined sugar feeds the bad bacteria in our gut, while natural sugar can feed the good.

The more unhealthy bacteria there are, the more you may crave the glucose they require to reproduce. This imbalance may make losing weight challenging, cause unwanted weight gain, and cause other digestive issues such as bloating, constipation and diarrhoea.

While slimming down, it’s imperative to look at the nutrition labels of foods to ensure they don’t contain excess sugar. Sometimes even foods that are marketed as healthy may actually contain high levels.

By consuming a diet high in fibre, protein and good fat, there won’t be a lot of space left to even care about sugary, processed foods as a result of being so full. Consequently, you’ll reduce your caloric requirement enough daily to meet your weight loss goals!

So besides from weight loss, what might be the effects of sugary foods on inflammation?

Sugar and inflammation

Inflammation is necessary for our healing. Our bodies release chemicals to protect from any potentially harmful organisms throughout injury or infection, which can result in warmth, redness, and swelling.

Therefore, eating too much sugar can cause chronic low-grade inflammation, which, much like weight gain, can increase the risk of heart disease, cancer and type 2 diabetes. 

Consuming a lot of sugary foods have been shown in animal studies to increase the likelihood of obesity, insulin resistance, increased gut permeability, and chronic low-grade inflammation. 

And the research doesn’t just back its effects on animals either, as studies on human have also demonstrated the association between refined sugar and inflammation. 

sugar and inflammation

For instance, research conducted on 29 healthy people showed that consuming only 40 grams of added sugar daily increased weight gain, inflammation, insulin resistance and bad cholesterol. 

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In comparison, a study on overweight and obese people found that drinking a fizzy drink every day for half a year increased uric acid levels, which can cause inflammation and insulin resistance, whereas participants who only drank diet soda, milk, or water had no increase in uric acid.

Furthermore, not only can sugary foods cause inflammation but also too many refined carbohydrates.

In one study, consuming only 50 grams of refined carbs exhibited an increase in Nf-kB’s inflammatory marker. 

And how does a high sugary diet physiologically lead to inflammation? 

Well, firstly, advanced glycation end products (AGEs) are dangerous compounds that build in blood when protein or fat bonds with sugar and excessive AGEs cause oxidative stress and inflammation.

Secondly, bacteria and toxins can move more easily from the gut into the blood, potentially causing inflammation. Excess bad cholesterol and body fat have additionally been linked with enhanced amounts of inflammation also. 

It’s important to note, though, that it’s not just sugary foods alone that causes inflammation but with the combination of other sources such as stress, medication and smoking etc. 

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Natural Sugar and inflammation

In the United States, around 12% of daily calories in adults come from refined sugar, which is quite high given that guidelines recommend no more than 5% to 15% of calories come from solid fats and added sugar.

Although excessive amounts of added sugar and refined carbohydrates have been linked to inflammation, as previously discussed, natural sugar has not been linked to inflammation and many natural sugary foods, like fruits and vegetables, may actually be anti-inflammatory.

A diet rich in whole foods such as fruits, vegetables, and whole grains can also provide additional health benefits. There’s no reason to restrict or avoid these foods.

So now that we’ve covered how sugary foods can cause inflammation, what can we do to reduce it?

How to reduce inflammation

Certain lifestyle modifications, such as lowering your sugar and processed food consumption, can lower inflammation.

Consuming fructose, for instance, has a dose-dependent effect on inflammation, meaning that the more you intake, the more inflammation there is in the body. Also, sedentary behaviour, smoking and chronic stress levels have been linked with low-grade inflammation.

One paper demonstrated that eating unprocessed foods to replace processed foods improved insulin resistance and cholesterol while reducing blood pressure, all related to inflammation.

Therefore we can reduce inflammation by restricting our intake of processed drinks and food. Also, choosing whole-grain carbohydrates such as oats, quinoa and brown rice can help us alleviate inflammation due to their fibre content.

Moreover, as fruits and vegetables contain micronutrients, these may aid in the reduction of inflammation. If you are wary of certain products, you can always read the nutrition label to look for ingredients like glucose, high-fructose corn syrup, and sucrose.

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Finally, what other long-term health problems may result from refined sugar?

Long-term health problems

Human research has linked added sugar and refined carbohydrate consumption to chronic diseases like heart disease, cancer, diabetes, and obesity.

Heart Disease

Some papers have demonstrated an association between sugary drinks and an increased heart disease probability. For instance, a study of more than 75,000 women exhibited that those who had a diet high in refined carbohydrates and sugar had up to a two-fold increased likelihood of heart disease than women with low consumption of refined carbohydrates.

The reason likely being that cardiovascular disease risk factors like increased bad cholesterol, blood pressure, insulin resistance and inflammation are influenced by the effects of sugar. 


Additionally, individuals have been shown to be at a higher risk of certain cancers from excessive sugar intake.  For example, a study of over 35,000 women’s diets discovered that those who ate the most sugary foods and drinks had twice the risk of developing colon cancer as those who ate the least amount of refined sugar.

Although research is still emerging, increased risk of cancer has been suggested to be due to sugary food’s impact on inflammation. 


Studies have also demonstrated increased consumption of refined sugar for type-2 diabetes.  A large analysis including almost 40,000 participants showed that only one serving of sugary drinks each day was linked with almost a 5th greater likelihood of obtaining type 2 diabetes.


In conclusion, added sugar can be detrimental to health for a variety of reasons.

When dieting, it’s crucial to address your sugar intake in the initial stages. Although there’s a possibility for added sugar to be included in a healthy lifestyle, like in your tea in the morning or for the occasional snack, it has to be consumed in moderation.

However, if you find it difficult to have it only once in a while, it may be better to avoid sugary foods altogether until you reach your ideal body weight.

Concerning inflammation, the literature is demonstrating that excessive sugar can be a contributing factor. Over prolonged periods, this inflammation can play a part in developing several health concerns like cancer, cardiovascular disease and type 2 diabetes.

Therefore, it’s important to take steps to control inflammation by exercising regularly, making informed dietary decisions and limiting stress.

If you are interested in undertaking one of our evidence-based and results-backed Plato Weight Management programs, please make sure to check what program may be suitable for you at this link or contact us here!

You can find out what some of our previous clients had to say about the program on our success stories page!


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