Sugar and the brain function

Sugar, sugar, sugar - the highly controversial member of the carbohydrate family, pop culture portrays it from so many different angles - vices, indulgences, fat gain, rowdy children, addiction, and the ultimate breakup antidote.

In this blog, we want to set the record straight on sugar’s irreplaceable role in your body, specifically in brain function, as well as the finer nuances of how to use sugar to your advantage rather than a detriment.


What is glucose?

Carbohydrates are one of the four macronutrients. Its main role in human survival is to provide energy. After we consume carbohydrate-rich foods, like fruits, grain products, and candies, our digestive system breaks larger carbohydrate molecules down to small building blocks, called sugars. In the body, our cells can easily turn a specific kind of sugar into energy to keep us alive - this type of sugar is called “glucose”.


Sugar & Cognitive Health

Sugar is considered a fast-absorbing fuel source in comparison to protein and fats. Once it is digested and absorbed into the bloodstream, it is carried around the body to be used by cells with the help of the hormone insulin.

There is one organ in the body that uses around 20% of sugar-derived energy, and that is your brain! Parts of the brain are very selective with the type of fuel it uses, and it uses a filtration system called the Blood-Brain Barrier to only allow glucose to enter. For this reason, our brains rely on incoming glucose to optimally function. (1)

This is why if you go extended periods without food you can experience cognitive dysfunctions, including brain fog, irritability, and poor memory retention.

And this is also why if you go on extremely low carb, low-calorie diets, your brain will desperately try to upregulate your hunger and food intake to ensure it can continue to get enough glucose to stay alive. In other words, those types of starvation diets will not yield sustainable, long-term results in weight loss. (1)


How much sugar is too much sugar?

Although glucose is an essential fuel for the brain, it is definitely possible to have too much of a good thing. The Standard American Diet is filled with foods that can easily break down into glucose or added sugars that contain glucose.

Excessive dietary sugar intake has been associated with the type 2 diabetes epidemic, as well as obesity, cardiovascular disease, dysbiosis, Alzheimer’s, and various cancers. (2) So, in order to lead a long, healthy life, there needs to be a mindful approach to consuming sugars - not too little, not too much.

The recommended daily intake of sugar is under 10% of total daily calorie intake, which is only 50g to 62g for diets aiming for 2000 to 2500 calories respectively. (3) The more exercise or physical activity one does, the more sugar will be needed to help recover and build muscle.

The thing is, 50g to 62g is VERY easy to exceed with the amount of added sugar in most processed foods.

For instance:

1 cup of generic granola can contain 21g of sugar

1 cup of fruit juice from concentrate can contain 25g of sugar

1 cup of strawberry yogurt can contain 18g of sugar

In this case, from breakfast alone, you have already exceeded your day’s sugar requirements.


Are all sugars created equal?

The best way to incorporate sugar in a healthy way into your diet is to stay informed about how much, where, and when you are consuming it.

Naturally existing sugars in fruits, raw honey, or fermented foods like R’s KOSO and plain yogurts tend to come with additional nutritional benefits, such as antioxidants, fibers, vitamins, and minerals! Let these types of sugar sources make up 80% of your sugar intake.

Added white sugars or refined syrups are usually very nutrient-void. In other words, they don’t offer many bonus health benefits aside from calories, so these should be kept to a small percentage of your total sugar intake. R’s KOSO is made without white sugar. The most of sugar found in R’s KOSO is fructose from fruits and vegetables.


Let's get started!

Keren Chen | CBT Nutritionist
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Original Photo by @_saki_yamamoto_






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