Sugar is one of the most harmful and addictive substances that you can consume and is associated with the exponential increase of many diseases in the past 50 years, from diabetes, to obesity, heart diseases and many others. It is also responsible for the constant struggle of millions of people to maintain a healthy weight.
Consuming moderate amounts of sugar naturally found in whole unprocessed foods (fruits, vegetables, dairy products...) is absolutely fine for a healthy individual. The danger comes from the large amounts of sugar that are added to most packaged foods.
An adult has about 4g of sugar in his/her blood, which is less than 1 teaspoon. But the average daily consumption of sugar exceeds 90g in most of the Western world: 90g in France, 93g in England, 96g in Australia and 126g in the US. This is more than 4 times the daily maximum of 20 to 40g (5 to 10 teaspoons) of free sugar recommended by the World Health Organization.
What is sugar and how do we process it?
Sugar comes in various forms such as glucose, fructose or lactose. It is found naturally in milk, fruits, vegetables and other whole foods. But it is also added to most processed and packaged foods, often in the form of high fructose corn syrup. It does not have any nutritional value: it contains no protein, vitamins, nutrients, healthy fats or enzymes that our body needs. We don't even need sugar for energy as our body can manufacture the glucose it needs from other macro nutrients.
Consuming glucose raises our blood sugar levels, which stimulates the release of insulin. The glucose enters our cells and is either used immediately to create energy or turned into glycogen to be stored in our muscles or liver for future use. When glycogen stores are full - which happens quickly if we eat a lot of carbohydrates or are not physically active, the glucose is converted into triglycerides and stored as fat.
Fructose is even worse as it cannot be stored in muscles but only in the liver. Due to limited storage, it is usually converted into fat, unless used immediately for energy. So, to stay lean, we should consume fructose-rich foods (even fruits) in moderation, and preferably just before exercising.
Eating sugar gives us a brief energy boost, quickly followed by a sharp drop in blood sugar, once the insulin has done its job. This results in the infamous “sugar crash”. We feel sluggish, fatigued, irritable, and start craving for our next sugar fix. Sounds familiar?
Why is sugar so bad for us?
Sugar is incredibly addictive. It impacts the same receptors as drug or nicotine and triggers the release of dopamine and serotonin. We feel high and want to eat more of it. But the brain adapts to release less dopamine and we need more sugar to feel the same high as before. We know that eating cookies is bad for us and we feel guilty when eating too many, but we simply cannot stop eating them.
Excess sugar increases our hunger and cravings. It contributes to leptin resistance: we feel like we are starving although we have had enough calories. If this was not bad enough, sugar does not lower ghrelin (the hunger hormone) as much as proteins, fats and fibres do. This pushes us to overeat without filling satiated.
Excess sugar makes us fat and is one of the leading causes of obesity. Eating sugar triggers the release of insulin that puts our body in a fat storage mode. A single cookie, a glass of orange juice or a smoothie raises insulin and stops any fat burning for up to several days for those who have a slow metabolism.
Too much sugar can lead to type 2 diabetes. The more sugar we eat, the more insulin is released. When too much insulin is released, our cells become resistant to its effects. If insulin resistance worsens, our body can no longer control blood sugar levels. Our levels skyrocket and we end up with type 2 diabetes.
Excess sugar raises bad cholesterol and the risk of cardio vascular diseases. It can lead to the accumulation of fatty, artery-clogging deposits in our blood vessels and to visceral fat build-up around our organs.
Sugar has been associated with an increased risk of getting certain cancers. Most cancer cells feed on sugar, consistently elevated insulin levels contribute to cancer growth and sugar drives inflammation (another contributor to cancers).
Excess sugar stresses the liver. The liver can only metabolise so much sugar (especially fructose) at a given time and starts turning the sugar we eat into fat. Overtime, this can lead to non-alcoholic fatty liver disease.
Sugar can accelerate the aging process, due to the production of advanced glycation end products. It also worsens wrinkles and can trigger skin issues.
Sugar is bad for our teeth. It feeds the bad bacteria in our mouth, which can lead to cavities, tooth decay or demineralisation.
Last, excess sugar is also associated with many other health issues such as an increased risk of developing Alzheimer‘s, Parkinson's, dementia, mental issues, depression and hypertension.
The hidden names of sugar and how much sugar is in our food
Added sugar hides in processed foods under more than 60 different names! The most common names include sucrose, high-fructose corn syrup, molasses, maple / rice / malt syrup, glucose, maltose, lactose, dextrose, cane / date / coconut sugar, juice concentrate, caramel, agave / fruit nectar.
Added sugar is not only found in all the sweet foods like cereals, baked goods, snacks, energy drinks and fruit juices. It is also in infant food and baby formula, salad dressing, sauces, pizza and many other packaged savoury foods.
So, next time you buy packaged food or drinks, check the ingredients! As a general rule, look for food with less than 5g of sugar per 100g. To give you an idea, just one of the foods and drinks below is enough to push you over your daily limit.
25 to 35g of sugar in 1 large apple, 2 medium cafe latte, 250ml of fruit juice, 1 banana, 1.5 cups of ice tea or 1 cup of kids' cereals with low fat milk
35 to 45g of sugar in 1 sweetened yogurt or 1 medium soft drink
more than 45g of sugar in 1 cup of milkshake, 1 medium smoothie or 1 large soft drink.
How to tame your sweet tooth and reduce your sugar intake
Eating whole unprocessed foods will automatically decrease the amount of sugar you consume.
Swap sugary drinks and juices for tea, coffee, or lemon & lime infused water. Replace desserts by cheese or fruits that are low in sugar (berries are the best option). Ditch cereals and orange juice for breakfast and enjoy eggs, bacon and avocado instead.
If you really need to sweeten your food or your mid-morning coffee, use natural sweetener such as stevia or erythritol. Xylitol is also an option but in moderation to avoid digestive issues.
When you quit sugar, wonders happen!
Ditching added sugar will reduce your hunger, eliminate cravings and bloating, stabilise your energy levels, enhance your mood and concentration, reduce inflammation and bad cholesterol, improve your skin health and help you better manage your stress, among others.
Not enough? It will also help you shed excess body fat without deprivation, delay aging by reducing oxidative damage, and reduce the risk of developing all these nasty modern diseases, such as cardiovascular diseases, diabetes and neuro-degenerative diseases.
Are you sure you still want this slice of chocolate cake?
See references here.