Diet & Nutrition

What is my carbohydrate tolerance and how do I find it?


Accredited practicing dietitian and founder of Menuconcepts shares her tips to manage your carb intake.

It is important if we have pre-diabetes or type 2 diabetes that we determine our carbohydrate threshold, and everyone’s carbohydrate threshold is different.

Many patients ask me how much carbohydrate they will be able to eat in the long term to keep their blood sugar levels in a healthy range, and to keep their weight down.

My answer is simple, everyone is very different, and everyone will tolerate a different amount of carbohydrate and have different carb thresholds or tolerance.

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How to calculate carbohydrate tolerance

The tolerance level is the amount of carbohydrate you can consume before your blood sugar levels start spiking and you gain weight. You might also experience other symptoms like tiredness, hunger and fogginess.

Some people may be able to tolerate 50 grams of carbohydrate per day and some people may be able to tolerate up to 100 grams per day, while others may only be able to consume 25 grams of carbohydrate per day.

It is important to determine your actual correct carbohydrate formula for you, and how much carbohydrate you can consume daily before it starts impacting your health, you gaining weight and your blood sugar levels are spiking high again.

The first thing you need to do is to understand how much total carbohydrate you are currently consuming each day, by counting up the total carbohydrate in all foods and fluids you are consuming over a day. You need to become a carbohydrate detective!

The best thing is to refer to the defeat diabetes carbohydrate food list so you can get a good idea of how much carbohydrate you are ingesting over the day.

Once you have a good idea of your current total carbohydrate intake per day. This is the starting point.

Secondly, you need to measure your fasting blood sugar levels in the morning, before you start eating for the day, and then measure over a week, so you can determine what your average fasting blood sugar levels are.

Thirdly, I suggest you then aim to go onto a low carb diet of 50 grams of carbohydrate per day. This will lower blood sugar levels on average over time and give you a benchmark to use as a measuring tool.

Once you’ve been following 50 grams of carbohydrate per day for at least a few weeks, or until your high blood sugar levels reduced down closer to a healthy fasting range of between 5-7 mmol/L, you then start adding back carbohydrate to determine how much you can tolerate before you start to see your blood sugar levels spikes again.

For example, if you consume 50 grams of carbohydrate per day for a few weeks and you see your blood sugar levels drop on average from 8 mmol/L to 6 mmol/L, fasted, you can then slowly add back more carbohydrate.

You might increase to 70 grams per day then 80 grams, then 100g per day, to determine how much carbohydrate you can have before you start to see your blood sugar spike up to 8 mmol/L again.

Once they spike you have reached your carbohydrate threshold or tolerance levels. You now know how much more carbohydrate you can have before you start to see your blood sugar spike and what grams of carbohydrate you need to stick to per day.

This is powerful information to have and will enable you to keep your diabetes managed well as long as you know your carb threshold and you do not exceed it!

So, in summary:

  1. Everyone has a different carbohydrate threshold or tolerance level, everyone can consume differing amounts of carbohydrate in their diet daily before they start to see their blood sugars rising and their weight going up, or before they start experiencing gastrointestinal symptoms such as bloating or tiredness and fogginess.
  2. To determine your carbohydrate tolerance or threshold level you need to start tracking how many grams of carbohydrate you are currently consuming per day and what your current average fasting blood sugar level is.
  3. You then need to reduce to a low carb intake of 50 grams of carbohydrate per day until your blood sugar levels drop to lower more healthier ranges.
  4. Then you can slowly start adding more carbohydrate back into your diet, and once you start to see your blood sugar levels spike and /or your weight going up this is your threshold or tolerance level, and you now know how much more carbohydrate you can tolerate.
  5. You need to become a carb detective using the Defeat Diabetes carbohydrate food list to calculate how much carbohydrate you are consuming each day.

Improving our blood sugar levels and weight, and defeating diabetes is determined by understanding how much carbohydrate and sugar our bodies can tolerate and knowing our carbohydrate threshold.

To learn more and to transform your health, start your free 7-14 day free trial of the Defeat Diabetes Program today. Find more from Nicole Moore here.