Healthy Eating and Gestational Diabetes

During pregnancy sometimes the body is unable to regulate blood glucose (sugar) levels normally because of hormonal changes. This is called ‘Gestational Diabetes’.

The sugar in the blood comes mainly from the sugar and starchy foods (carbohydrates) we eat, and some glucose is produced by the body overnight.

Will it go away after I have the baby?

After delivery blood glucose levels usually return to normal. You will have a blood test to check your glucose levels are back to normal 13 weeks after the birth.

Will I develop diabetes?

Having high blood glucose levels in pregnancy increases the risk of developing diabetes later in life. It is important to have your glucose levels checked every year. By doing this, if you develop diabetes it can be picked up early and treated. See the section at the end of this booklet on how to prevent diabetes.

Will it harm my baby?

Having high blood glucose levels in pregnancy may cause your baby to grow abnormally large. Controlling your blood glucose levels may help. It may also help with your baby’s health after delivery.

What should my blood glucose levels be?

Aim to have your glucose levels less than 5.3mmol before breakfast. Also check your glucose level 1 hour after each meal and these should be less than 7.8mmol. If they are outside of this range three times in 48hours, or there is a pattern of being above range at a particular time of day, then contact your Diabetes Specialist Nurse or Dietitian.

General dietary principles

Follow these steps to help control your sugars:

There is no need to ‘eat for two’ even if you are expecting twins or triplets. To manage feeling more hungry, eat regularly during the day. Try to have 3 small meals and a small snack between each meal.

  • Eat plenty of vegetables and up to 3 portions of fruit each day.
  • Cut down on added sugars and sweet foods, and avoid sugary drinks (this includes fruit juice and smoothies).
  • Try to choose higher fibre foods throughout the day.
  • Eat less fried and fatty foods, or high fat snacks.
  • Limit alcohol intake. Not drinking alcohol at all is the safest approach for your baby. (1)

Each of these steps is discussed in more detail in the following pages.

Physical activity

Along with eating well you should try to take regular exercise each day.

  • Keep up with your normal daily physical activity or exercise for as long as you feel comfortable. Don’t exhaust yourself. You may need to slow down as your pregnancy progresses.
  • Moderate-intensity exercise (where you are still able to hold a conversation) is not dangerous for the baby. However, do avoid contact sports (squash, kickboxing etc) and undertake activities that have a risk of falling (e.g. cycling) with caution.
  • If you weren’t active before you got pregnant, don’t suddenly take up strenuous exercise. Start with low intensity sessions for no more than 15 minutes and increase this gradually.
  • Being physically active helps lower your blood glucose levels. It can also make your muscles use insulin more effectively. Try to take a walk (up to 30 minutes) after meals to improve blood glucose control.
  • If you have any concerns about your pregnancy/baby and exercise then do not hesitate to contact your midwife or doctor.

Planning your meals

The diagram below shows the ideal amounts from different foods in your meal.

Half of your meal should be vegetables or salad. A quarter of your meal should be starchy/carbohydrate foods and the other quarter should be meat, fish, cheese, eggs or pulses.

Carbohydrates (starchy foods)

Your body breaks down carbohydrates into glucose (sugar). It is important to not cut these foods out completely as they are the main source of energy for your body and your growing baby. Try to have a small portion (quarter of a plate) at each meal, as per the diagram above.

All types of carbohydrates can be eaten, but some will raise your blood glucose levels less than others, even when an appropriate portion size is eaten. Try to eat more of the higher fibre, more slowly absorbed carbohydrates, as per the
list below:

  • Breakfast cereals many of our patients find breakfast cereals cause blood glucose levels to rise too much. Try lower carbohydrate alternatives such as natural yogurt and fruit, or eggs with one slice of seeded bread.
  • Grains: two tablespoons cooked bulgur wheat, quinoa, semolina, couscous, pearl barley.
  • Rice: two tablespoons steamed/boiled Basmati rice (white or brown).
  • Pasta: three tablespoons of cooked pasta, all kinds.
  • Potatoes: two - three egg-sized new potatoes, small (fist-sized) sweet potato (with skin).
  • Bread: two medium slices of seeded, granary or rye bread, or one pitta bread.

Fruit and vegetables

Aim to have at least 2 to 3 portions of vegetables or salad and two or three portions of fruit and each day.

A portion of fruit is:

  • One large fruit e.g. apple, small banana, pear, orange.
  • Two small fruits e.g. plums, apricots, prunes.
  • Two tablespoons stewed (without added sugar)/ tinned fruit in juice (drained).
  • Eight to ten large grapes or cherries.

A portion of vegetables is:

  • Two to three tablespoons of cooked, raw, frozen or canned vegetables or beans e.g. broccoli, cabbage, carrots, cauliflower, courgette, french green beans, mushrooms, peas, peppers, spinach etc.
  • Small bowl of salad e.g. lettuce with cucumber, tomatoes, onions and pepper.

Meat, fish, cheese, eggs, nuts and beans

Choose two to three small portions (size of the palm of your hand / deck of playing cards) each day from the following list:

  • Lean meats or poultry (chicken or turkey) without skin – try not to add extra fat or oil when cooking. Make sure it is cooked all the way through.
  • Fresh or frozen fillet of fish (see note below) - preferably not in batter or breadcrumbs.
  • Eggs - cooked without fats and oils.
  • Cheeses - low fat pasteurised soft cheeses or small amounts of hard cheese.
  • Baked beans, lentils, kidney beans, chick peas and similar beans, tofu.

Note: Oily fish such as fresh tuna, sardines, pilchards, mackerel, trout, kippers, herrings, or salmon may be beneficial for you and the baby, however do not eat them more than twice a week. Avoid shark, swordfish and marlin. Limit the amount of tuna you eat to four medium tins a week.

It is also recommended you avoid liver. For further information see:

Sugary foods and drinks

Aim to keep your intake of sugary foods and drinks as low as possible. Sugar is a concentrated form of carbohydrate and can raise your blood glucose levels quickly.

Foods to avoid

  • Sugar added to drinks and cereals
  • Sugar-containing drinks
  • Ordinary milky drinks such as drinking chocolate, malted milk drinks
  • Sugary puddings and desserts, such as sponges, pies and tarts
  • Ordinary milk puddings and instant desserts
  • Full fat yoghurts containing cream
  • Ordinary jelly
  • Fruit canned in syrup
  • Packets of dried fruit

Foods to try instead

  • Tablet or sprinkle sweeteners such as Canderel, Splenda, Hermesetas, Silver Spoon Sweetener, Truvia
  • Low calorie, sugar-free or diet squash, fizzy drinks and flavoured waters
  • Cocoa and a sweetener.
  • Low calorie drinking chocolate.
  • Low-calorie or sugar-free desserts and milk puddings
  • One scoop of ice-cream
  • Low fat natural or greek yoghurts
  • Sugar free jelly
  • Fresh fruit, fruit stewed without sugar or fruit canned in juice (juice poured away)

Eating less fat

Most people eat too much fat. Eating less fat, especially saturated fat, will reduce your risk of heart disease and diabetes later in life. Fats are particularly ‘energy-dense’ and therefore are high in calories. Reducing your overall fat intake will help control your weight during pregnancy which will also help with your glucose levels.

Ways to have a lower fat intake

  • Ready meals, fast foods and takeaways may be high in fats.
  • Look for ones with less than 5% fat (less than 5g fat per 100g of the product)
  • Eat fewer pies, pasties, pastries, crisps, nuts, corn or potato snacks (crisps), cakes, desserts and biscuits.
  • Limit roast potatoes or chips to once a week or less.
  • Limit cheese to four ounces (100g) a week. Try a low fat variety and try grating cheese to make it go further.
  • Use skimmed, 1% or semi-skimmed milk rather than full cream milk.
  • Use tomato or vegetable-based sauces for pasta rather than cream or cheese based sauces.
  • Choose plain fish rather than fish in batter or breadcrumbs.
  • Use a spray bottle or measure out oil with a teaspoon.
  • Limit high fat ‘extras’ such as salad dressing, mayonnaise, nut butters to a teaspoon serving.

Reducing fat intake when cooking and preparing food

  • Use all fats, spreads and oils sparingly. Try using a spray bottle, or measuring out with a teaspoon to limit how much you use.
  • Grill, casserole, microwave or bake foods rather than frying it.
  • Use low fat yoghurt rather than cream, sour cream or crème fraiche in cooking or on desserts.
  • Remove skin and visible fat from meats before eating.

Switching to healthier types of fat

Although all fats are high in calories and therefore can lead to weight gain if eaten in too large a quantity, not all fats have the same effects on the body.

Saturated fats (see below for examples) tend to raise the ‘bad’ cholesterol levels in the body. These fats are usually hard or solid at room temperature.

Hydrogenated vegetable oils, also known as ‘trans-fats’ also increase the ‘bad’ cholesterol levels in the body. Trans-fats are no longer used by UK food manufacturers, but foods made outside of the UK could still contain trans-fats.

Unsaturated fats (see below for examples), particularly monounsaturated fats and fish oils, offer more benefits to
your health.

Saturated fats - to avoid

  • Butter, ghee, lard
  • Dairy fats including whole milk, full fat hard cheese, cream, creme fraiche, soured cream and ice-cream.
  • Hydrogenated vegetable oil
  • Meat products, including sausages, pies and suet
  • Palm oil, coconut oil and coconut cream
  • Biscuits, cakes, chocolate confectionary and pastries

Unsaturated fats - to choose instead. Use small amounts of:

  • Spreads labelled ‘high in mono-unsaturates’ e.g. olive oil, rapeseed oil, vegetable oil
  • Rapeseed oil (vegetable oil), olive oil, sunflower oil, soya oil
  • Oily fish e.g. salmon, trout, fresh tuna, mackerel, herring
  • Nuts, seeds and avocado


  • Most people consume far more salt in their food than their body needs. If you have high blood pressure, you may be able to reduce it by taking less salt.
  • Use less salt in cooking. Use herbs, spices, vinegar and pepper instead.
  • Avoid adding salt to meals at the table.
  • Cut back on salty foods such as cheese, processed meats and ready-made dishes.


Aim to have at least eight cups of fluid each day e.g. water, tea, coffee, no-added-sugar squash and diet drinks.

It is best to avoid fruit juice and smoothies even if it is labelled no-added- sugar as they can still contain a large amount of natural sugars.

Please note that you do not need to cut out caffeine completely but it does need to be limited. For further information see:


If you are eating smaller meals than normal, you may feel the need to have a snack between each meal. Try not to have a snack until you have checked your blood glucose levels 1 hour after a meal.

Examples of suitable snacks include one of the following options:

  • A portion of unsalted nuts (20g serving/ a few in the palm of the hand).
  • One hard-boiled egg.
  • Vegetable sticks with a teaspoon of houmous, cottage cheese or low fat cream cheese.
  • One portion of fruit.
  • One to two plain rice cakes, oatcakes or crispbreads topped with a slice of ham, cottage cheese, avocado or teaspoon of peanut butter.
  • A portion (approx. 125g) of low fat plain, natural or greek yoghurts.
  • Glass of skimmed or semi-skimmed milk.
  • Small packet of lower fat crisps (occasionally) e.g. Popchips™, Walkers Oven Baked™, Walkers French Fries™.
  • One to two plain biscuits e.g. rich tea, malted milk, shortcake.

Changing your habits

It is not always easy to stick to a sensible eating plan. Eating is often triggered by certain situations, emotions or feelings, not just physical hunger. Changing the way you think about eating can take time but it will help you keep your blood glucose levels under control.

Keep a food, mood and blood glucose diary

This can be a useful start. It may help you understand your eating patterns and how they affect your blood glucose levels. Be honest and write down everything you eat and drink for a few days.

Make a note of:

  • When you ate or drunk.
  • How much you had.
  • Where you were.
  • How you felt and what were you thinking at the time and afterwards.
  • What happened to your blood glucose levels.

Looking at your diary

A few questions to think about:

  • Did you find it more difficult to make helpful choices and control your portion sizes at a particular type of day?
  • Did your eating behaviours change if you went too long between eating and got overly hungry?
  • Was there a difference in your eating at times when you had planned and prepared what you were going to eat beforehand?

Did some foods increase your glucose levels above 7.8mmol?

  • Could you consider having a smaller portion or an alternative option next time?
  • Some mothers find ‘pairing’ carbohydrates with a protein or a small portion of a healthy fat can help to prevent post-meal spikes. For example:
    • A portion of fruit with a teaspoon of no-added-sugar nut butter/ thin slice of cheese.
    • Slice of seeded toast with a poached egg/tbsp of mashed avocado/ tsp of no-added-sugar nut butter.

Please note: For some expecting mothers it is not possible to manage their blood glucose levels through dietary changes alone and it may be necessary to start medication to help. Please do not feel that you have ‘failed’ if this is the case.

Ideas for Meals


  • One small portion of berries with 125g (small pot) low-fat natural or greek yoghurt.
  • One slice of granary, seeded or rye bread/toast with one of the following: a little low-fat spread / avocado / teaspoon of nut butter / boiled or scrambled eggs / 1/4 can (100g) no-added-sugar baked beans / tinned or grilled tomatoes, spinach and mushrooms / slice of ham, tbsp cottage cheese, sliced cucumber and tomatoes / tinned fish in tomato

Quick meals

  • Sandwiches (made with granary, seeded or rye bread) with salad and tinned fish, lean meat or eggs, with some chopped vegetables on the side.
  • Lentil or vegetable soup and a small bread roll with some low fat cream cheese.
  • Small (fist-sized) baked sweet potato with filling such as baked beans, cottage cheese or tuna, served with a
  • side salad.
  • One to two slices of granary, seeded or rye toast, topped with baked beans, egg, tinned fish, cheese, tomatoes or mushrooms.
  • Tinned fish in tomato sauce on bread or toast with low fat spread.

Main Meals

  • Lean roast meat with boiled or dry-roasted potatoes and a selection of vegetables.
  • Small bowl of pasta with a tomato-based sauce and bowl of salad.
  • Fish or cottage pie served with peas or a green vegetable.
  • Vegetable or lean meat curry with rice and salad.
  • Spaghetti Bolognese made with very lean mince and served with a salad
  • Stews and casseroles made with lean meat and vegetables.

After the Birth

Aim for a healthy weight and lifestyle to prevent diabetes.

After you have had the baby, losing the weight you have gained during pregnancy and continuing to eat a healthy diet is important for your long term health. This will help to reduce your chances or delay you developing diabetes.

If you are breastfeeding do not try to ‘diet’ until you stop.

It is usually better to make small changes to your eating habits which can be sustainable, rather than go on a ‘crash diet’ which you cannot keep to for long. A healthy rate of weight loss is about 0.5kg (one pound) a week.

The best way to lose weight is:

  • To keep a better balance of foods at meals.
  • Look at your portion sizes.
  • Limit snacks.
  • Limit fatty and sugary foods.
  • Avoid sugary drinks and excessive alcohol intake.

It is also helpful to increase the amount of physical activity you take. If you can, be more active. Build up to 30 minutes walking or other activity each day.

Further pregnancy

If you decide to have another baby, you may be more likely to have abnormal blood glucose levels again. You will be asked to have a glucose tolerance test at booking, and again at around 16 weeks.


  1. NHS Choices. Your pregnancy and baby guide.
  2. Diabetes UK. Diet and lifestyle with gestational diabetes. (Online). [Last accessed 16th January 2019]:
  3. National Institute for Health and Care Excellence (NICE). Diabetes in pregnancy: management from preconception to the postnatal period. NICE Guideline 3:

If you or the individual you are caring for need support reading this leaflet please ask a member of staff for advice.

How to contact us:

North Bristol NHS Trust
Gate 10, Level 6
Brunel building
Bristol BS10 5NB

See your appointment letter for the number to phone with any queries you may have.

© North Bristol NHS Trust. This edition published April 2021. Review due April 2023. NBT03191.