Between the traditional morning tea or coffee, the little treats we enjoy most days and then the industrially prepared meals, sugar is everywhere in our food. With the irresistible urge to come back for more again and again... This "sugar mania" is also fed by the food processing industry, most often without our knowledge.

Scientific data shows the harmful effects on health of excess sugar consumption. Excess weight, metabolic problems with an explosion in the number of cases of diabetes, inflammatory diseases, cardiovascular diseases, tooth decay…

It is a public health issue that led the World Health Organisation (WHO) to issue a recommendation in March 2015 that free sugar in food should be limited to below 10% of daily energy intake (50 grammes or 8 sugar cubes).

There's not one single sugar, but many !

In this article we are focussing on the simple sugars that are rapidly assimilated by the body (table sugar, brown sugar, fructose, corn syrup, fruit juices, etc.) and not the complex sugars that are slowly assimilated that come from cereals, beans, pulses, potatoes, bananas, etc.


Sweetening power

Base components

Source - where is it found?



Fructose + glucose

Sugar extracted from cane or beet. Table sugar, preserves, desserts…



Glucose + galactose

Milk and dairy products.



Glucose + glucose

Preserves, jam, beer, ketchup, sweet potatoes.




Bread, biscuits, sauces, energy drinks.

Glucose syrup

27 à 55

Various glucoses

Cakes, pastries, jam, ice cream, ketchup.


110 - 120


Drinks, ice cream, biscuits, jam, industrial bakery products.

Fructose syrup

90 ou 100


High usage in the USA. Increasing usage in Europe.

Invert sugar (mixture of glucose syrup and fructose syrup in equal concentrations)

100 - 110

Glucoses + fructoses

Preserves, cakes, gingerbread, biscuits

Isoglucose (mixture of glucose syrup with a proportion of fructose) or glucose-fructose syrup

Similar to saccharose

Glucoses + fructoses

Industrial bakery products, fruit fillings, fizzy drinks (particularly in the USA)

When sugar plays hide-and-seek

In the 1960s sugar was mostly consumed as saccharose (60% to 80%) in powder or cube form and added to food; "home made" was the order of the day. Sweet foods generally formed part of traditional celebrations such as Shrove Tuesday, Easter, Christmas and New Year. As society evolved, its use was magnified by certain restaurants and high-profile chefs using high amounts of sugar...

Industrially prepared foods and meals then became more and more common, from breakfast to main meals and snacks enjoyed by young and old alike! And this is the crux of the problem: sugar has been slipped in just about everywhere, of course into sweet-tasting products but also into others that are not sweet to the taste (soups, bread, pickles, savoury biscuits, ketchup, cooked meats, sauces, salad dressing, balsamic vinegar, stock cubes, crispbreads, prepared meals, frozen foods...).

Almost our entire current sugar consumption (80%) comes from processed foods, most often in the form of glucose, fructose or glucose-fructose syrup.

Hunting down the sugar: decoding food labels !

Sugar comes in dozens of different names.
First look out for terms ending in '-ose', including syrups (see table above).

And here are some other names for sugars: sorghum syrup, maple syrup, carob syrup, corn syrup, date syrup, starch syrup, agave syrup, cane juice, cane juice crystals, grape sugar, coconut sugar, malt extract, diastatic malt, diastase, modified starch, molasses, dextrin, dextran, maltodextrin, fruit juice, grape juice, apple juice, muscovado.

And, of course, honey and caramel.

From pleasure... to addiction

To enhance the taste or to preserve, soften, crispen, colour, improve texture, ferment... industrial producers believe the addition of such sugars to be indispensable. Could it also be to make us want more? It has been demonstrated that the more we consume sugar, the less reactive become the dopamine receptors on which it acts to give us the pleasurable sensation; so we need higher quantities! This is added to the fact that sugar has a turbulent effect on our glycaemia, or blood sugar level, producing the well-known "hypo effect" when it suddenly drops down again producing a feeling of dizziness and sugar cravings. A vicious circle!

Our body is unable to handle excessive consumption !

The main source of energy for our cells, glucose (and not sugar), can be considered to be the body's fuel. Under the action of digestive enzymes, carbohydrates lead to the formation of glucose, fructose and galactose, the latter two of which can also give rise to glucose. Glucose is made available to the cells via insulin, a hormone secreted by the pancreas. Its role is to transporter blood glucose to the cells of the muscles and liver and to the fat cells where it is used. But too much glucose disrupts the metabolism. When the cells are constantly subjected to high doses of insulin due to high levels of glucose, they react and the number of insulin receptors reduces on the membranes: this is known as insulin resistance. The pancreas must produce more and more insulin to use up the glucose… In the long term, this can cause type 2 diabetes with high blood sugar levels causing harmful effects.


Fructose is metabolised very differently from glucose: its processing by the liver leads to the formation of uric acid and produces enzymes that promote the production of triglycerides in the blood (a risk factor in atherosclerosis), the increase of fat in the liver (risk of steatosis or "fatty liver") and fat storage, notably in the abdomen. Chronic consumption leads to hypertension, to insulin resistance much faster than with glucose, weight gain and even obesity, metabolic syndrome, diabetes and stimulates the reward system leading to the desire to eat more.

Fruit also contains fructose, as do beans and pulses, but consumption is nevertheless recommended!

When you eat fruit, beans or pulses, the absorption of fructose by the intestine is significantly slowed down by the fibre. They also contain naturally beneficial antioxidants and phytonutrients. The maximum content of fructose is an average of 10g for fruit and 4g for beans and pulses. So it is not possible to exceed the liver's capacity to metabolise fructose from fruit, beans and pulses.

The danger actually lies with the intake of fructose that is added to food, in other words in forms that are not natural. So we should limit or even eliminate consumption of fizzy drinks, iced teas, energy drinks..., preserves, jam, biscuits, prepared foods… but also fruit juices and compotes which no longer bear any resemblance to fruit and with which the fructose is digested very rapidly.

Be careful also of agave syrup and coconut syrup which mainly consist of fructose.

Sugar and health

Numerous studies have shown the harmful effects on our body of excess sugar. Here are the main ones.


  • Inflammation of the hippocampus, the memory zone => cognitive impact with memory problems.
  • Higher secretion of dopamine and serotonin followed by a sudden drop => further need = just like a drug with symptoms of depression.
  • Type 3 diabetes? = increased risk of Alzheimer's disease.

Overconsumption of fructose = malfunctioning communication between the neurones, possible cause of depression and anxiety.


  • Sugar nourishes the bacteria that form caries = multiplication and formation of acids that attack the teeth. Saccharose is also a major cause of caries as well as all fizzy drinks with high acidity.


  • Hypertension (via the increase of the levels of cholesterol and triglycerides). Fructose has the highest impact: consumption of 74g of fructose per day, or 4 cans of fizzy drink => increase of between 28% and 87% of the risk of hypertension.


  • A high level of sugar in the blood => long-term damage to the small blood vessels in the kidneys => renal failure over time.


  • Modification of the intestinal flora: predominant fermentation flora => imbalance promoting the development of candidiasis and hyperpermeability with all the consequences... and diminished natural defences.

Sweeteners also modify the intestinal flora and cause weight gain.

  • Impact on the liver of sugary drinks: more than 1 a day => non-alcoholic hepatic steatosis (fatty liver).


  • Excess sugar => increased secretion of insulin by the pancreas => storage of glucose in the cells and notably in the fat cells (adipocytes). In the long term, resistance to insulin => type 2 diabetes.
  • Excess sugar + fat (as with numerous industrially produced foods) => weight gain or even obesity => metabolic syndrome (abdominal corpulence + high level of triglycerides + hypertension + high glycaemia) => type 2 diabetes.
  • By secreting inflammatory components that accumulate in the liver, visceral fat can trigger an inflammatory reaction.
  • Regular consumption of fizzy drinks is linked to a higher risk of developing type 2 diabetes.
  • Fructose causes a sensation of hunger and the desire to eat (unlike glucose).

Sweeteners cause havoc with the metabolism via the microbiota. Regular consumption of sweetener => development of an intolerance to glucose with the high risk of metabolic syndrome and type 2 diabetes.


  • As it ages our body naturally produces components that are difficult to break down, glycotoxins, which result from the combination of sugars and fats with certain proteins.

    Nowadays, this reaction is increasing in proportion to the consumption of sugar components cooked at high temperature (such as biscuits) and to the incidence of metabolic syndrome, obesity and type 2 diabetes (the greater the amount of sugar, the greater the amount of proteins combined with the sugars).

    The accumulation of glycotoxins causes a cellular reaction with an inflammatory response which may cause tissue lesions (skin, cartilage, etc.): this causes accelerated ageing.
  • Sugar is an acid-forming food. Consumed in excess it leads to an acidic-demineralised environment.

    To neutralise any such overproduction of acid, the body eats into its alkaline mineral reserves (magnesium, potassium, calcium) and the acids lead to chronic inflammation. (acid environment link)

The journalist from ELLE magazine specialising in health and wellbeing tested out a sugar-free diet lasting one year.
Personal testimony, surveys and practical advice. A mine of information. A really good read.

Zéro sucre
Danièle Gerkens
Editions Les Arènes • april 2015

To reveal the hidden sugar in 1,500 foods. An essential book

Le compteur de glucides
Magali Walkowicz
Editions Thierry Souccar • april 2015