Diet and exercise with type 1/2 diabetes

Try to eat a healthy, balanced diet and stay active throughout your pregnancy. This will help you keep your blood sugar levels under control.

Your diet in pregnancy 

It’s important to have a healthy, balanced diet. This will help you keep your blood sugar levels under control and reduce the risk of complications.

Speak to your healthcare team for dietary advice suitable for your condition and needs.

Keep an eye on your portion sizes

How much you eat during a meal is just as important as what you eat. Friends and family might encourage you to have extra food or snacks because ‘you’re eating for 2 now’. This is actually a myth and isn’t true.

You don’t need to eat any extra food in the first 2 trimesters of pregnancy. In the third trimester, you may need to eat around 200 calories extra a day, which is around half a sandwich. 

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

Taking supplements

Folic acid

If you have diabetes, you will need to start taking a high dose (5mg) of folic acid every day from as soon as possible when you find out you are pregnant until you are 12 weeks pregnant. This is taken as a tablet (supplement) and reduces the risk of having a baby with spina bifida or other problems affecting the baby's spine and neural tube. 

You’ll need to get a prescription for this from your GP because you can’t get a higher dose of folic acid over the counter. 

Vitamin D

Anyone who is pregnant or breastfeeding should take 10 mcg of vitamin D every day throughout their pregnancy. Vitamin D keeps your baby’s bones, teeth and muscles healthy. 

Find out more about taking supplements in pregnancy


There is no proven safe amount of alcohol you can drink during pregnancy. If you drink alcohol during pregnancy, some alcohol will pass through the placenta to your baby. The more you drink, the greater the risk of harm to your baby. 

If you have type 1 or type 2 diabetes, alcohol can affect your blood sugar levels. For example, it can:

  • make it more difficult to see the signs of hypoglycaemia
  • make hypoglycaemic episodes last longer
  • delay a hypoglycaemic episode until hours after you’ve had some alcohol. 

Avoiding all alcohol during pregnancy is the safest option. Find out more about drinking alcohol during pregnancy.

Staying active in pregnancy

Exercise is not dangerous for your baby. Some people worry about their baby being shaken around while they exercise, but this won’t happen. Your baby is safe and secure within your womb and may even find the movement relaxing.

If you have always been active, it’s usually safe and healthy to continue to exercise at the same level during pregnancy. If you have not been active before, you can start to build up your level of activity now. You can start by following our 10 tips for staying active in pregnancy.

The benefits of exercise

If you have type 2 diabetes, physical exercise helps lower your blood sugar level.  Talk to your diabetes team about how you can exercise safely during pregnancy.

If you have type 1 diabetes, exercise and sport affects your blood glucose levels. Depending on the type of exercise or sport you do, it can cause your blood glucose levels to rise (hyperglycaemia) or drop (hypoglycaemia). For example, intense or unplanned exercise can cause hypoglycaemia. 

Try to:

  • check your blood glucose level before and during exercise – this will help you work out what you should eat and when to adjust your insulin
  • record your blood glucose levels and what you eat when you exercise – share this with your diabetes team to help find what works for you
  • check your blood glucose levels regularly after exercise (they can drop up to 12 hours after exercise) – you may need to take extra carbohydrate or a lower dose of insulin before bed
  • if you exercise, it's likely you'll need extra carbohydrate to prevent hypos
  • drink plenty of water while you exercise. 

'I was advised to continue running because my body was used to it – I managed to run up until I was 4 months pregnant. When I felt unable to run anymore I did pilates and swimming, which I found hugely beneficial.' 


Managing your weight in pregnancy with type 1 or 2 diabetes

If you eat well and exercise, you should be able to keep to a healthy weight during pregnancy. 

Most diabetes pregnancy services will weigh you at every visit. This is because you are more likely to have a large baby (macrosomia) if you gain a lot of weight during your pregnancy. 

Everyone gains weight differently in pregnancy so there are no official guidelines for how much weight you should gain. The most important thing is to keep your weight gain to a safe and healthy level for you and your baby. Find out more about how much weight you should gain during pregnancy

Do not try to lose weight when you’re pregnant. Even if you are classed as obese, dieting while you’re pregnant may harm the baby. Just try and concentrate on eating well. If you do, you may not gain any weight while you’re pregnant and you may even lose a little bit. This won’t harm your baby.   

Find out more about being overweight and pregnant

Your team will support you and give you advise about how to keep yourself and your baby healthy if they feel that your weight is an issue.

Find out more about managing your weight in pregnancy

NICE (2010) Weight management before, during and after pregnancy. Available at: (Accessed 16 December 2023) (Page last reviewed: 28/07/2010)

NHS (2021) Diabetes and pregnancy. Avialable at: (Accessed 16 December 2023) (Page last reviewed: 09/06/2021 Next review due: 09/06/2024)

NHS (2020) Vitamin D. Available at: (Accessed 16 December 2023) (Page last reviewed: 03/08/2020 Next review due: 03/08/2023)

NHS (2023) Exercise in pregnancy. Available at: (Accessed 16 December 2023) (Page last reviewed: 15/03/2023. Next review due: 15/03/2026)

NHS (2020) Food and keeping active with type 2 diabetes. Available at: (Accessed 16 December 2023) (Page last reviewed: 18/08/2020. Next review due: 18/08/2023)

NHS (2023) Low blood sugar (hypoglycaemia). Available at: (Accessed 16 December 2023) (Page last reviewed: 03/08/2023 Next review due: 03/08/2026)

NHS (2021) Exercise and sport. Available at: (Accessed 16 December 2023) (Page last reviewed: 06/08/2021. Next review due: 06/08/2024)

RCOG (2022) Being overweight in pregnancy and after birth. Available at: (Accessed 16 December 2023) (Page last reviewed: 08/2022)

Review dates
Reviewed: 20 July 2020
Next review: 23 July 2023

This content is currently being reviewed by our team. Updated information will be coming soon.