Are you confused about carbs?

Carbohydrates provide energy for the body, but they turn into sugar in the bloodstream, causing blood sugar levels to rise rapidly. To be able to follow a good diet for gestational diabetes, it is beneficial to understand which foods and drinks contain carbohydrates.

high carb foods
Macronutrients impact on blood glucose

If carbs raise blood sugar levels, why can’t we just cut them out completely?

Simple answer; No.

Cutting carbohydrates out of the diet or severely restricting them will lower blood sugar levels, but this causes the body to go into a state of ketosis, burning fat for energy instead of glucose. It can also make you feel lethargic too.

The problem with burning fat instead of glucose is that when you are pregnant, the acid that is produced as a result of the body doing this, called ketones, can be harmful to the growing baby if ketones are produced in very high amounts.

Therefore it is important to continue to eat small amounts of carbohydrates at each meal where possible and to stay well hydrated. You can read more about ketosis on our ketones page.

ketones ketosis and ketoacidosis

Different types of carbs

When thinking of carbs, many people think of starchy carbs such as bread, pasta, rice and potatoes.

bread, pasta, potatoes and rice - starchy carbs

However, carbohydrates can be found in most foods and drinks

  • sugary drinks
  • sugary foods: cakes and pastries
  • sweets
  • sugars, jams, honey and syrups
  • dairy products: milk, yoghurt
  • fruit and fruit juices
  • vegetables
  • nuts
  • seeds
  • grains and flours
  • sweeteners

Carbs are made up of three different things: sugar, starch and fibre.

Simple carbs

Simple carbs are quickly broken down and digested, meaning they can spike blood sugar levels rapidly. 

Simple carbs are naturally occurring in many foods:

  • fructose in fruit
  • lactose in milk and yoghurt
  • sucrose in table sugar

Simple carbs are also found in sweets and sugary treats.

simple carbs fruit fructose
simple carbs lactose from milk
simple carbs sucrose from sugars

Complex carbs

Starch is a complex carbohydrate made of sugar units bonded together.  Starch occurs naturally in vegetables, grains, and cooked dried beans and peas.  

Complex carbs come in two types:-

Refined complex carbs – When a complex carb is refined, it is processed, and much of the fibre and goodness is stripped away, e.g. white flour

Unrefined complex carbs  – Unrefined carbs are, therefore, carbs that are in their natural state and contain much more goodness, e.g. wholemeal flour

starchy complex carbs

Comparing refined and unrefined complex carbs

Golden rule#5. Low amounts of unrefined complex starchy carbs at every meal

For better blood sugar levels, we need to select unrefined complex carbs which have more fibre, like brown, whole wheat and whole grain varieties, which take longer to digest, resulting in a lower and slower release of sugars.

Refined complex carb ×Unrefined complex carb 
White flourWholemeal flour
White breadGranary or wholemeal bread
White pastaWhole wheat pasta
White riceBrown or whole grain rice
Breakfast cerealsSteel-cut/pinhead porridge oats
refined complex carbs white carbs
unrefined complex carbs brown whole grain and wholewheat carbs

Fibrous complex carbs

Golden rule#6. Bulk up meals with lots of vegetables and salad

Vegetables are fibrous complex carbs. They contain many important vitamins, minerals, and fibre, which are good for digestive and bowel health and have been found to be beneficial to postprandial [post-meal] blood sugar levels.

fibrous complex carbs

The amount of carbs in vegetables varies, with sweeter, higher starch vegetables like carrots and sweetcorn being higher in carbs and green leafy vegetables having much less.

For this reason, bulk meals with plenty of leafy salad and green vegetables.

Reading food labels

The traffic light system showing details on the front of packaging in the UK does not show carbohydrates. It shows sugars, so it can show if a product is low, medium or high in sugars. However, as carbs turn into sugar in the body, it’s essential to look at the detailed nutritional information to see the total carbs in a product.

A mixture of macronutrients: is it a carb, protein or fat?

Macronutrients are the food groups: carbohydrates, fat and protein.

Many foods and drinks are a mixture of macronutrients, which can also be confusing. For example, yoghurt has carbohydrates from lactose, fat and protein.

Baked beans are a good source of protein, but they are also high in carbs, so baked beans served on top of a baked potato or a piece of toast which are also high in carbs will cause higher blood sugar levels.

potatoes and legumes are carbs

The best products to help with a gestational diabetes diet and to lower blood sugar levels will be low in carbohydrates but high in fats and protein.

You can view the best yoghurts I have found on my best yogurts page.

Carb counting

A commonly used method for helping to control blood sugar levels is carb counting. This is where the patient is given a guide amount of carbs in grams to eat for each meal and snack eg. 20g breakfast, 40g lunch, 60g dinner and 15g for snacks.

Carb counting works to a point, giving some guidance to carb portion sizes, but it can also mean that the mother may unecessarily over-restrict certain carbs and force themselves to eat to others, as fits within the carb allowance.

Each person tolerates different carbs, meaning one person could tolerate a good-sized serving of brown rice, but cannot tolerate the smallest serving of potato or fruits. Whereas the next person could eat potatoes without any high blood sugar levels, yet really struggle with bread and pasta.

If following advice that you can eat a set amount of carbs per meal, it can cause confusion if you cannot eat the serving of carbs suggested. This can also lead to medication being introduced and doses of medication increased to keep blood sugar levels normalised.

carb counting examples

People with Type 1 diabetes use carb counting to work out insulin doses versus the carbs eaten. But as gestational diabetes insulin resistance fluctuates with hormones in pregnancy, it can make judging insulin doses more difficult. This can lead to unstable blood sugar levels and more hypos.

A better way than counting carbs in grams

Trial and error with starchy complex carbs is the best approach at the start, so try different ones and keep a food diary alongside your readings to refer back to.

You will find starchy complex carbs which YOU tolerate better than others

Start with small servings (use the visual below for a starting amount). Depending on your readings increase the carbs in small amounts so that you are comfortably within your test target for blood sugar levels and reduce or restrict the carbs that you don’t tolerate so well.

starting point for starchy carbs
tweaking carbs

If you cannot tolerate ANY starchy complex carbs then you should contact your diabetes team as it may mean that you require help with medication or increased doses.

Never eat a ‘naked’ carb!

Golden rule#2. ‘Food pairing’

There is something you can do to slow down the release of sugar from the carbohydrates into your bloodstream. You can ‘pair‘ carbs to make them more tolerable.

Eating carbohydrates with protein and natural fats will slow down gastric emptying and the release of glucose meaning you are less likely to spike blood sugar levels too high.

Making sure you “never eat a naked carb” means that you always add protein and natural fats e.g. a slice of Livlife bread toasted (one of our better-recommended breads) will give higher blood sugar levels if only eaten with butter. Adding peanut butter or eggs mean the protein and natural fats will slow down the absorption of glucose and will give better blood sugar levels.

The Glycaemic Index

Different types of carbohydrates are digested at different rates in the body and this has an effect on blood glucose levels. The Glycaemic Index (GI), is a system of ranking used to understand how quickly these foods make blood glucose levels rise after eating them (or spike).

Low GI foods should be used to help make better choices when selecting which carbohydrates to eat, swapping high GI foods for low GI instead for a better gestational diabetes diet.

A list of better options and quick swaps for a gestational diabetes diet
Carbohydrate foodBetter options for GD
BreadsBurgen soya & linseed, multigrain, rye, pumpernickel bread, Hi-Lo, wholemeal sandwich thins, Lidl low GI bread, 400g slices of wholemeal/granary bread see my post on best bread here
CrackersOatcakes, Ryvita, whole wheat crackers & wholegrain crispbreads
Potatoesnew potatoes, sweet potatoes small or half a jacket potato and mash may be tolerable but they must be paired with protein & natural fats – add cheese, butter and cream
Pasta and noodleswholewheat pasta & noodles cooked until al dente
RiceBasmati or brown wholegrain rice
GrainsQuinoa, wholegrain couscous
Breakfast cerealsPinhead porridge oats (not rolled oats – these are still not tolerable to many)
FruitTart/sharp berries, Granny Smith apple, kiwi, small sharp citrus fruits
Fruit juices & carbonated drinksWater, no added sugar squash, diet/zero drinks. See our drinks information
Sugars, syrups, honeySweeteners
Cakes, biscuits & pastriesNairn’s oat biscuits, hobnobs, digestives, rich tea
Jams & preserves (avoid even diabetic jams)Peanut butter (<7g total carb per 100g), marmite, cheese spread
DessertsSugar-free or no added sugar jelly, no added sugar angel delight/shops own brand no added sugar ‘delight’
Sweets & chocolateDark chocolate, ½ Kinder Bueno, Cadbury’s Freddo, treat size chocolate buttons. See our chocolate post
MilkWhole (full fat) milk, soy milk, almond milk, coconut milk, Lacto-free milk
YoghurtsCoconut milk yoghurt, full-fat Greek yoghurt, soya yoghurt. See our posts on the best brands of yoghurt here
‘Carb Hacks’:

Why am I getting high levels with good, healthy breakfasts?

We often see mothers confused as to why their recommended breakfasts of cereal, skimmed milk and fruit with a small glass of orange juice have caused them to have high blood sugar levels. So let’s look at this advice…

Cereal = complex carb (could be refined or unrefined depending on the cereal)

Skimmed milk = simple carb (from the lactose in the milk)

Fruit = simple carb (from the fructose in the fruit)

Orange juice = simple carb (from the fructose in the fruit, juicing also means the fruit is broken down even more, and the sugars will be more easily absorbed).

Carbs turn into glucose in the bloodstream, so you are effectively eating sugar + sugar + sugar, with a drink of pure sugar with very little protein and fat to help pair the carbs = an almighty spike in blood sugar levels! Or you may see a crash in levels dropping very low, which could be a sign that you’ve spiked and crashed.

healthy high carb breakfast