Gestational diabetes and your diet

Eating well is an important part of managing gestational diabetes and staying healthy throughout your pregnancy.

Making changes to your diet will help you manage your blood sugar (glucose) levels and your weight, which will reduce the risk of pregnancy complications. You should be referred to a diabetes specialist dietitian, who can give you advice about your diet and how to plan healthy meals.

When you start making changes, bear in mind what foods you should avoid during pregnancy, such as some types of fish and cheese.
Making a few simple changes can go a long way. The main thing is to eat a healthy, balanced diet. 

If you’re not sure where to start, check out our meal ideas for gestational diabetes. We’ve listed lots of meals that could help you control your blood sugar levels, with meal prep ideas for breakfast, lunch, evening meals and healthy snacks. 

Diabetes UK also has some recipes for people with gestational diabetes that you could try.

The glycaemic index (GI)

Your healthcare professional will talk to you about the glycaemic index (GI). This is a rating system that shows how quickly carbohydrate foods affect your blood sugar level.

This sounds complex, but it’s just about swapping out some foods for others to help control your blood sugar levels. 

High GI carbohydrates raise your blood sugar levels quickly, which is not good if you have gestational diabetes. These foods include:

  • sugary drinks and processed foods (such as cake, biscuits, sweets, ice-cream)
  • many breakfast cereals
  • fruit juices
  • white bread
  • potatoes
  • white rice.

If you have gestational diabetes, low or medium GI foods are better for you, because they raise your blood sugar levels more slowly. You may hear these called slow-release carbohydrates. They include:

  • some fruit and vegetables (such as berries, plums, broccoli, peppers)
  • pulses (such as chickpeas, lentils)wholegrain foods (such as wholegrain bread, porridge oats).

Find out more about the glycaemic index and a helpful list of foods to eat.

Eat regularly

It’s important to eat regularly – usually 3 meals a day – and avoid skipping meals. 

Start with a light breakfast and aim to have regular meals, with healthy snacks if you feel hungry in between. It is helpful to always carry healthy snacks with you, such as pieces of apple or pear. It can help you avoid convenience foods such as biscuits or sugary drinks.

Snacks can be particularly important if you take insulin, which can cause your blood sugar levels to fall too low (known as hypoglycaemia). Your diabetes team should give you information about hypoglycaemia, including suitable snacks to help manage it.

Cut down on sugar

Eating too much sugar will make it hard to manage your blood sugar levels. Use artificial sweeteners instead of sugar where possible, and try not to eat too much honey or syrup. Replace chocolate and other sugary snacks with healthier options, such as oatcakes or sugar-free jelly.

You could also try leaving sugar out of recipes when you’re cooking – it often makes little difference to the flavour. And don’t forget that many fizzy drinks are high in sugar.

Processed and fast foods such as takeaways and ready meals can sometimes contain more sugar than you’d expect, so always check the packaging on the foods you buy.

Watch your portion sizes

How much you eat during a meal matters as much as what you eat. You may have been looking forward to having extra food because you thought that being pregnant meant ‘eating for two’. This might be tempting, but sadly it's not true.

You do not need any extra food in the first six months of pregnancy. After that, you only need an extra 200 calories a day, which is about half a sandwich.

Find out more about how much extra you should eat in pregnancy.

Research has also shown that the amount of carbohydrates you eat has the biggest impact on your blood sugar levels after meals. 

This means that even if you’re eating well, you may struggle to manage your diabetes if you’re eating too much carbohydrate. Starchy carbohydrates should only make up about a quarter of what you eat.

Diabetes UK has more information about how to get portion sizes right.

Think about what you drink 

You need to think about what you’re drinking too. Try to avoid sugary drinks (unless you’re having a ‘hypo’). Diet or sugar-free drinks are better, and you could try water flavoured with mint or fresh fruit. Fruit juices and smoothies can be high in sugar, as can drinks labelled as ‘no added sugar’. Check the label or ask your healthcare team if you’re unsure.

“I had a bizarre craving for fresh orange juice when I was pregnant. But when I was diagnosed with gestational diabetes my midwife advised me to cut it out because of the sugar content.”


As water contains no carbohydrate or calories, it is the perfect drink during pregnancy. Studies have shown that drinking water could help control blood sugar levels, too. Drink a large glass of water with every meal and more in between meals.

“Water was key to keeping my glucose levels stable. I drank about 3 to 4 litres a day and walked for half an hour after dinner. My rule was a pint of water with every meal and one immediately after. It worked for me and others I know.”


Find out more about how much water you should drink during pregnancy.

Look closely at low-fat options

If you often choose low-fat foods, now is the time to look more closely at the labels. This is because:

  • Low-fat options sometimes contain more sugar than their full-fat versions.
  • Fatty foods can slow down the release of sugar from carbohydrate, helping to stop your blood sugar from spiking.

Choose foods with natural fats, such as:

  • milk
  • olive oil
  • eggs
  • seeds
  • avocado
  • natural or Greek yoghurt.

Tips on meal planning with gestational diabetes

Planning ahead can help you choose healthy meals that will help control your gestational diabetes. Try not to go shopping on an empty stomach, as you may be more likely to buy unhealthy foods.

Many people like to plan their meals for the week ahead of time. Not only can this help you get a balanced diet, it can also save you money! Check out our meal ideas for gestational diabetes when making your weekly shopping list.

Diabetes UK also has a range of sample meal plans that can help you decide what to buy and manage your diet.

What else can I do to improve my diet?

You should also try to:

  • Eat plenty of fruit and vegetables – aim for at least 5 portions a day.
  • Swap cakes and biscuits for healthy alternatives, such as fruit, nuts and seeds.
  • Eat lean sources of protein, such as chicken, fish, tofu or beans.
  • Choose lower GI options by swapping white bread for wholegrain.
  • Cut back on salt – too much salt is linked with high blood pressure, which can increase the risk of pregnancy complications.

Remember that everyone is different

What works for some people might not work for you. For example, some people find that even healthy, lower-GI foods such as porridge oats increase their blood sugar levels. Try not to get frustrated if you find it hard to manage your blood sugar levels at first. You will quickly learn what works for you.

You may also find that the way your body responds to certain foods changes throughout your pregnancy. For example, foods that work well for you in early pregnancy may cause higher blood sugar levels later on.

“I had to be very strict and found it was harder to get good glucose readings the further along I was, even with the same foods that had been fine for ages.” 


“If I had bread it would be wholegrain, and just one slice. Then fish and vegetables and some cheese. And oatcakes! Oatcakes were the things that saved me!” 


What else can I do to manage gestational diabetes? 

As well as eating well, exercise can help lower your blood sugar levels. Walking for 30 minutes every day is one way to keep active during pregnancy, and can help to lower your blood sugar levels.

Some people with gestational diabetes can keep their blood sugar under control using diet and exercise alone. But no matter how hard you try, you might not be able to manage your blood sugar this way. If this happens, you may be offered medication

Tablets and insulin cannot replace diet and exercise. It’s still really important to keep your healthy habits going.

Talk to your healthcare team if you have any concerns about managing your condition, such as how to eat well with gestational diabetes. You can also talk to the Tommy’s Midwives Helpline on 0800 014 7800 (Monday to Friday, 9am to 5pm), or email us at [email protected].

“Following a low-carb, high-fat, high-protein rule worked. I managed to avoid insulin and also lost excess weight I was carrying around for no reason. My little boy was born a healthy 6lb 10.” 


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Review dates
Reviewed: 15 February 2024
Next review: 15 February 2027