We need glucose to live. Our brain needs about 130 g of glucose a day. We can get this from our diet, or when carb intake is low (for example if you were fasting) we can get it from gluconeogenesis or ketosis, as long as we have enough protein and fat to process.


This is important to understand that while our body needs a certain amount of glucose, that glucose can come from several sources.


Just like there is no single “best diet”. There is no “correct” amount of carbohydrates that is the same for everyone all the time.

Carb intake will depend on factors like:

• How big or small someone is
• How big or small someone IS;
• How much lean mass or body fat they have;
• How active they are;
• How intense, long-lasting, and / or frequent that activity is;
• How old they are, and what stage of life they are at;
• Intake levels of other macronutrients;
• Genetics;
• What they want to do.

For example
The carbohydrate needs of a young muscular male athlete who trains twice a day will need a lot more carbohydrates than a sedentary 68 year old woman who does tai chi 3 times a week.


When it comes to carb intake, there is a distribution of how intake will vary. Most people will be somewhere in the middle, doing best with a moderate portion of carbs, especially from higher fibre, nutrient rich slow digesting sources such as vegetables, fruits and whole grains.

When it comes to carbs we suggest as often as possible stick to less processed, whole foods with slow digesting carbohydrates. keep it complex,but when thinking about nutrition as a whole, try to keep it simple.

Make sure you are eating the right foods, in the right amounts, for the right reasons.
1. how much food are you eating each day? are you eating the right amount for your goals?
2. how are you eating each day? are you slowing down to savor and digest?
3. why are you eating each day? are you truly hungry when-you eat?
4. what are you eating each day? are you sticking to mostly whole foods?
5. are you going #1 to #4 consistently? are you doing this 75-90% of the time?

Many of you may be familiar with this term, its used to market certain carbohydrate and grain products as being “better for you”
But what does it mean?
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The glycemic index (GI) is the measure of the rate of which an ingested food causes the level of glucose in the blood to rise. This tells us how much blood sugar goes up when we consume 50 g of usable carbohydrates from a particular food.
It is a relative measure determined against a specific reference food.

In general the less processed and higher fibre a food is, the more complex its carbohydrate molecules usually are. Due to this , these foods typically take longer to digest and have a lower GI.

High glycemic foods include sugar, candy, breakfast cereal and bagels. Lower GI foods include legumes, whole grains and vegetables.

When blood sugar goes up quickly, insulin is usually quick to respond. The amount of insulin released usually matches the amount of glucose present.

This had led to some people to suggest that a low GI diet is a healthy one.

While GI is an interesting measure of the physiological response to carbs in the diet, it does not tell the entire story.

1. We don’t eat most foods by them selves (for example you would not just eat bread on its own). Protein, fat and fibre all change GI  level , eating carbs as part of a full meal will change GI levels.
2. Many factors can affect how quickly a food is converted to glucose, including:
   when we eat that meal during the day
   Wether we have been active
   This can vary person to person, day to day and meal to meal.
3. The GI score can be easily manipulated by the TYPE of sugar in the food. Foods with large amounts of fructose tend to have low GI scores, because fructose does not immediately raise blood glucose levels. But that does not mean foods any healthier.
4. The GI index is based on a standardised amount of carbohydrates not a standardised amount of food. In order to calculate GI of carbohydrates we’d only need a small amount of sugar, but quite a lot of carrots for example. Making this an unrealistic comparison.

Researchers often use glycemic load as a more realistic measure. The glycemic load of a food is based on the GI X by the serving size of the food.
While this gives a better picture of how fast blood sugar may go up after a meal, GL still has some of the same problems as GI. And it does not take into account other elements like fibre, micronutrients, phytonutrients etc.

The GI and GL does not give us the whole story. Most people should not be using these (or any numbers) to dictate what and how they should eat and enjoy.
Nutrition is not black and white, carbohydrates and most foods are more complicated than this.

Barardi et all 2018 The Essentials of Sport and Exercise nutrition Third Edition.
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