Care at NUH

Flexible Mealtime Insulin Dosing and Carbohydrate Counting

2024/09/27
HOW CAN PRACTICING FLEXIBLE MEAL-TIME INSULIN DOSING BENEFIT YOU?
The rise in blood glucose levels post-meal is primarily influenced by carbohydrate intake. 

Flexible insulin dosing enables you to  adjust the amount of quick-acting insulin to match the amount of carbohydrates you are planning to consume. 


Balancing carbs and insulin

How will learning flexible meal-time insulin dosing benefit you?

This approach offers flexibility to enjoy a broader variety of foods with increased confidence, while avoiding high or low blood glucose levels after a meal.
HOW TO GET STARTED?

To successfully implement flexible meal-time insulin dosing, you will need to learn the following:

Practice flexible meal-time insulin dosing

CARBOHYDRATES

Types of Macronutrients

Carbohydrates are a major macronutrient in a balanced diet, alongside proteins and fats. ​Types of Macronutrients

More On Carbohydrates

Carbohydrates are categorised as follows: 

1. Sugars

These are simple carbohydrates that are rapidly absorbed, leading to quick increases in blood sugar levels. Common sources include sugar-sweetened beverages like sodas, packet drinks and sweets. 

 

2. Starches

These are complex carbohydrates that are broken down into simple sugars upon digestion.

Refined grains are starches  which have undergone processing and have lower fibre and nutrient content. They tend to can cause quick spikes in blood sugar levels. Examples include white rice, corns flakes, and products made from white flour, such as white bread.

Whole grains, being less processed and higher in fibre, are the preferred choice, as they help to stabilise blood sugar levels. Examples include brown rice, whole grain bread and oats.

 

3. Fibre

These are complex carbohydrates that are indigestible and do not contribute to blood glucose increases. They can also slow down the digestion and absorption of sugars.  

 

Although carbohydrates (sugars and starches) are the main contributors to post-meal glucose rise, avoiding carbohydrates may lead to excessive protein and fat consumption and potentially cause weight gain. A balanced meal following the  healthy plate concept offers long-term health benefits and is more sustainable over time.

ADVANCED CARBOHYDRATE COUNTING

You might already be familiar with basic carbohydrate counting using the carbohydrate exchange system. This approach groups foods based on their carbohydrate content, with each exchange equating to 15 grams of carbohydrates. 

Advanced carbohydrate counting goes a step further, focusing on counting carbohydrate intake more accurately in grams. Accurate carbohydrate counting leads to a more accurate dosing of quick-acting (bolus) insulin and thus better glucose control.

In order to accurately estimate the amount of carbohydrates, you will need the following: 

1. Measurement of serving size of the food item you are planning to eat
Measuring can be done by weighing the food item or using household measures such as cups, spoons, or bowls. 

For example: 

  • A standard Chinese rice bowl (300ml), tightly packed with rice, contains about 60g of carbohydrates. 
  • One cup of milk (250ml) contains about 15g of carbohydrates. 

 

2. A reference of how much carbohydrates (in grams) per portion size of the food
We have compiled information on the average carbohydrate content of commonly consumed foods for your reference.  

If the food items come with nutrition labels, do refer to it for more accurate carbohydrate counting.

In addition, you can also refer to online reference databases (see next section). 

 

Grains, Cereals & Breads

Food ItemPortion Size (Weight of food)CHO (g)CHO exchange
(1 exchange = 15g of carbohydrate)
Rice (white or brown), cooked, tightly packed1 rice bowl (200g)60g4
Porridge1 rice bowl (260g)30g2
Beehoon, plain, cooked1 rice bowl (180g)45g3
Kway teow, plain, cooked1 rice bowl (150g)42g3
Noodles, egg, cooked1 cup (160g)38g2.5
Spaghetti, plain, boiled1 cup (140g)43g3
Cornflakes1 cup (30g)26g2
Oat, rolled, raw½ cup (45g)27g2
Chapatti1 piece (45g)21g1.5
Plain Thosai, small1 piece (45g)18g1
Idli1 piece (75g)16g1
Bread, wholemeal1 slice (30g)12g1
Cream crackers3 pieces (23g)14g1
Starchy Vegetables
Food ItemPortion Size (Weight of food)CHO (g)CHO exchange
Potato, raw, with skin1 whole, medium (150g)20g1
Mashed potato½ cup (120g)19g1
Sweet potato, raw, peeled1 piece (65g)12g1
Pumpkin, boiled1 cup (245g)9g0.5
Corn on cob, raw1 whole (300g)32g2
Legumes
Food ItemPortion Size (Weight of food)CHO (g)CHO exchange
Baked Beans, canned½ cup (125g)22g1.5
Sambar, dhal curry1 cup (285g)21g1
Chickpeas, boiled⅓ cup (50g)14g1
Red kidney beans, raw½ cup (90g)56g4
Milk & Diary
Food ItemPortion Size (Weight of food)CHO (g)CHO exchange
Milk, plain, low fat or skim1 cup (250ml)13g1
Low fat natural yoghurt1 small tub (200g)12g1
Common Hawker Centre Food
Food ItemPortion Size (Weight of food)CHO (g)CHO exchange
Chicken Rice, with steamed chicken1 portion (330g)73g5
Nasi Lemak with fried chicken wing1 plate (412g)109g7
Nasi Briyani with chicken1 plate (377g)102g7
Lontong with Sayur Lodeh1 plate (775g)64g4
Claypot Rice1 plate (597g)93g6
Seafood Fried Rice1 plate (428g)125g8
Century Egg Porridge1 soup bowl (512g)34g2
Ban Mian Soup1 portion (648g)38g2.5
Sliced Fish Beehoon Soup (no evaporated milk)1 soup bowl (686g)48g3
Mee Rebus1 plate (571g)82g6
Mee Siam1 plate (655g)92g6
Beehoon Soto1 soup bowl (900g)31g2
Chicken Macaroni Soup1 soup bowl (480g)30g2
Ang Ku Kueh with Peanut filling1 piece (68g)26g2
Deep Fried Carrot Cake1 piece (130g)27g2
Chee Cheong Fun, plain, with sauce2 rolls (202g)51g3
Curry Puff, potato1 piece (107g)37g2.5
Vadai with kacang Hitam1 piece (60g)10g1
Vegetable Samosa1 piece (75g)22g1.5
Gado Gado1 plate (421g)44g3


Source: HPB Energy & Nutrient Composition of Food

ONLINE RESOURCES FOR CARBOHYDRATE COUNTING

There are many online references for carbohydrate content available. These include websites and smartphone applications, with some specifically focusing on local foods, which can be more helpful.  

It is advisable to cross-reference information from multiple sources to get a more reliable estimate, as different databases or apps might offer varying values.

When using these resources, pay attention to the portion sizes. Makes sure to estimate the carbohydrate amount based on the serving size you are intending to eat.

Here are some resources to start with: 

ResourceFormat
HPB Energy and Nutrient Composition of FoodWebsite
NbuddySmartphone app
My Fitness PalWebsite, smartphone app
INSULIN:CARBOHYDRATE RATIO (ICR)

The insulin-to-carbohydrate ratio or ICR refers to how many grams of carbohydrate one unit of quick-acting insulin can cover.

 

Insulin : Carbohydrate ratio (ICR) example

The ICR varies from person to person and may differ at various times of the day. Working with your healthcare team is key to establishing an accurate ICR for your needs.

PUTTING INSULIN:CARBOHYDRATE RATIO (ICR) AND CARBOHYDRATE COUNTING TOGETHER

When both the ICR and carbohydrate counting are accurate, you will observe that your post-meal blood glucose levels do not rise more than 3 to 4 mmol/L. Additionally, the glucose level should return to pre-meal targets approximately 5 hours after eating (Figure 1).

Increase in blood glucose after meal

You can check if your ICR is correct under the guidance of your healthcare team.

If you find that your glucose readings are consistently exceeding the above thresholds after a ameal, then you have given insufficient quick-acting insulin, or underestimated the amount of carbohydrates in the meal.

WHAT OTHER FOOD-RELATED FACTORS AFFECT POST-MEAL BLOOD GLUCOSE LEVELS?

While carbohydrate content is the primary factor affecting post-meal glucose levels, other food-related aspects also play a role.

The glycaemic index (GI) of a food, for instance, indicates how quickly it can raise blood glucose levels. Foods with a higher GI cause faster increases in blood glucose levels.

FactorHow it affects the post-meal glucose reading
Type of carbohydrate (simple/refined vs complex)

 



Simple sugars and refined carbohydrates have a higher glycaemic index (GI) and absorbed more rapidly than complex carbohydrates, which are fibre-rich. 


If post-meal blood glucose levels spike but return to target range quickly, consider substituting simple or refined carbohydrates with complex, fiber-rich options.

For example, opt for brown rice (lower GI) over white rice (higher GI). 

How the carbohydrate is prepared


The glycaemic index of food can be affected by cooking methods such as boiling, frying, baking and roasting.

Other food preparation factors / processing methods i.e. long cooking duration, juicing, mashing or grinding could increase the glycemic index of the food and cause blood sugars to rise more quickly.


Be aware of how different preparation methods affect the GI. For example, al dente pasta has a lower GI compared to well-cooked soft pasta. 

What the carbohydrate is eaten with

Consuming carbohydrates as part of a balanced meal with moderate amounts of protein, fat and fibre can lower the glycaemic index, leading to a slower rise in blood sugar levels. 


However, a large intake of protein and/or fat with carbohydrates might cause a delayed and prolonged blood glucose increase. Monitor blood glucose trends and consult your healthcare care team for strategies if you notice a pattern of delayed glucose spikes. They can provide advice on managing the combined effect of carbohydrates with high protein or fat meals.

 

Last updated on
Best viewed with Chrome 79.0, Edge 112.0, Firefox 61.0, Safari 11
National University Health System
  • National University Hospital
  • Ng Teng Fong General Hospital
  • Alexandra Hospital
  • Jurong Community Hospital
  • National University Polyclinics
  • Jurong Medical Centre
  • National University Cancer Institute, Singapore
  • National University Heart Centre, Singapore
  • National University Centre for Oral Health, Singapore
  • NUHS Diagnostics
  • NUHS Pharmacy
  • Yong Loo Lin School of Medicine
  • Faculty of Dentistry
  • Saw Swee Hock School of Public Health
Back to Top