Care at NUH

Flexible Mealtime Insulin Dosing and Carbohydrate Counting


The rise in blood glucose levels post-meal is primarily influenced by carbohydrate intake.

Flexible insulin dosing enables the adjustment of quick-acting insulinin accordance with the amount of carbohydrates consumed. 

Balancing carbs and insulin

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

This approach offers the ability to enjoy a broader variety of foods with increased confidence, while managing blood glucose levels effectively 


To successfully implement flexible meal-time insulin dosing, it is useful to master the following aspects:

Practice flexible meal-time insulin dosing

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 

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 

Complex carbohydrates that are broken down into simple sugars upon digestion. 

Refined grains, which have undergone processing and have lower fibre and nutrient content, 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 complex carbohydrates are indigestible and do not contribute to blood glucose increases. They can also slow down the digestion and absorption of sugars.  

While carbohydrates (sugars and starches) significantly impact post-meal glucose levels, completely avoiding them may lead to excessive protein and fat intake, potentially causing weight gain.  

A balanced meal following the healthy plate concept offers long-term health benefits and is more sustainable over time.


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 measuring carbohydrate intake in grams. This precise approach enhances the accuracy of quick-acting (bolus) insulin dosing and, consequently, improves glucose control. 

Key components of advanced carbohydrate counting: 

1)      Measurement of serving size 

Accurately measure the serving size of the carbohydrate-rich food you plan to consume. This can be achieved by weighing the food 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)      Carbohydrate reference per portion size  

Familiarise yourself with the carbohydrate content in grams for various portion sizes. We have compiled information on the average carbohydrate content of commonly consumed foods for your reference.  

Additionally, nutrition labels on food items offer more precise data for carbohydrate counting. For further accuracy, online reference databases are also available (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
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


Numerous online references are available to assist with carbohydrate counting. These include websites and smartphone applications, with some specifically focusing on local foods, which can be more beneficial.  

For enhanced accuracy, it's advisable to cross-reference information from multiple, as different databases or apps might offer varying values. 

Always pay attention to portion sizes to ensure that the carbohydrate content corresponds to the actual serving size you plan to consume. 

Here are some resources to start with: 

HPB Energy and Nutrient Composition of FoodWebsite
NbuddySmartphone app
My Fitness PalWebsite, smartphone app

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

Insulin : Carbohydrate ratio (ICR) example

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. 


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

Increase in blood glucose after meal

Monitoring your ICR and its effectiveness can be done under the guidance of your healthcare team. 

Consistently exceeding the outlined thresholds may indicate an underestimation of carbohydrate intake or insufficient insulin administration. 


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. These methods influence the speed at which starch breaks down and sugars are released. 

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 or fibre can lower the GI, 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