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Nutrition and Dietetic Service
Ipswich Hospital
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Dietary advice for diabetes during pregnancy (gestational diabetes)

This booklet aims to provide you with guidance and information to help modify your diet and manage your gestational diabetes, enabling you to make the choices that are right for you.

Diet has a key role in managing gestational diabetes, as well as making sure you get all the nourishment that you and your developing baby need. The right balance of a variety of foods is particularly important at this time.

Sometimes changing your diet alone is enough, but you may also need to take medication. This will be discussed with your midwife and when you attend the Antenatal Clinic.

What happens in the body without diabetes?

Before we look at what diabetes is, it’s useful to think about what happens in the body that doesn’t have diabetes.

When we eat, our food enters the stomach and is broken down into many things, including glucose (sugar) – used in our cells as the body’s main source of fuel).

The glucose then enters the bloodstream. The rise in blood glucose triggers the release of insulin (a hormone produced by the pancreas – the diagram below shows where the pancreas is located).

Insulin is like a key. It opens the door on the cell, allowing the glucose to flood in and be used as energy to fuel the body.
The level of glucose in the bloodstream then returns to normal (4–7mmol/L) and the insulin has done its job. This process happens each time we eat, making sure that our body gets the energy we need and that our blood glucose level is nicely controlled.

What happens in gestational diabetes?

An increase in pregnancy hormones and other factors interferes with the action of insulin. It is this effect, combined with the increased demand on the pancreas (from the growing baby) to produce more insulin, that causes the sugar from the foods you eat to remain in the bloodstream. This increases your blood glucose above normal levels, which is not healthy for you or your baby.

Why keep to blood glucose level targets?

If your blood glucose levels are above target, the glucose can cross your placenta causing your baby to grow larger than normal, increasing the chance of complications in labour and delivery. It also increases the risk of your baby being overweight or obese and/or developing Type 2 diabetes in later life.

The aim of treatment

Treatment for gestational diabetes aims to achieve near normal blood glucose levels:

• before meals: < 5.3mmol/L;
• one hour after meals: < 7.8mmol/L.

A normal blood glucose level in someone without diabetes is 3.5–6.7mmol/L before eating.

There are five main principles for managing gestational diabetes

• Eat regular meals.
• Eat a varied and balanced diet (as for any pregnancy).
• Take care with your choice of starchy foods – choose higher fibre and watch your portion sizes.
• Cut down on food and drinks containing sugar.
• Do some physical activity every day.

Eat regular meals

Spreading your food intake over the whole day helps your body to keep your glucose levels more stable.

• Eat three meals each day (breakfast, lunch and evening meal).
• Try to have three medium-sized meals rather than one or two small meals and one large meal. You may need to aim for 30g of carbohydrate and include protein with carbohydrate in your meal as this will help lower your blood glucose level after eating.

Can I have snacks? (See our booklet – Diabetes in Pregnancy: Can I have snacks?)

If you are hungry between meals and want to snack, think about whether what you choose to eat will cause your blood glucose level to rise.

Aim for no more than 10g of carbohydrate as a snack. An acceptable choice might be:

• a piece of fruit
• one pot of yoghurt
• Two to three breadsticks/ rice cakes/ crackers with cheese spread or a
  dip.
• Try to time your snacks for two hours after and one hour before one of your main meals. For ideas, ask for our leaflet ‘Snacks and Diabetes’.

Eat a varied and balanced diet (as for any pregnancy)

• Eat a varied diet, as represented in the eat well guide. Doing this, together with eating regular meals helps to ensure you and your baby get all the nutrients that you both need.

Fruit and vegetables

These provide important vitamins, minerals and fibre. You should aim to eat 5 portions per day so include them at meals and as snacks.

Will these foods increase my blood glucose levels?

• Fruit contains natural sugar (fructose) and should therefore be limited to one portion (something that fits in your hand*) at a time, aiming for no more than three portions spread throughout the day (guidance on this will depend on your blood glucose levels).
  Examples of one portion of fruit are:
• a medium apple, orange, pear or peach
• Half a large or one small banana
• Two plums or satsumas
• Half a cup of berries such as strawberries or raspberries
• 6 to 10 grapes (depending on size); or one small slice of melon or pineapple.
• Vegetables and salad will have very little or no effect on blood glucose levels and therefore make great snacks. Try carrot and cucumber sticks with tomato salsa dip or celery and cream cheese or hummus. See our snacks booklet for more ideas.

Discuss with your dietitian the best time to include fruit and fruit yoghurts.

Milk and dairy foods

These are excellent sources of calcium. Aim to have at least three portions of these foods per day. Examples of one portion are:

• 190ml (one third of a pint) milk
• 150g yoghurt
• 30g hard cheese (choose from those suitable in pregnancy). These foods also provide us with iodine. Also see ‘Do I need nutritional supplements?’ Soya milk (choose ‘unsweetened’) is supplemented with calcium, but not iodine.
• If you are using milk alternatives please discuss this with the dietitian.

Will these foods increase my blood glucose levels?

• Milk and yoghurt (but not cheese) contain a natural sugar (lactose).
• Milk: Be careful how much milk you have at a time – stick to one portion, as suggested above.
• Yoghurts: These can be high in sugar and total carbohydrate. Aim for those with less than 10g of carbohydrate per pot (or less than 10g per 100g). Suitable options include:
• Shape or Activia 0%
• Weight Watchers
• Muller Light (smaller pots) Danone Light and Free Greek-style yoghurt.

Meat, fish, eggs, beans and other non-dairy sources of protein such as nuts, pulses, dahl, Quorn and tofu

These are a good source of iron. Include these foods at least once daily. Try to eat at least two portions of fish per week, one which should be oily fish (such as mackerel, trout or herring).

Will these foods increase my blood glucose levels?

These foods will have very little or no effect on blood glucose levels. You may find that increasing the portion size of these foods can help you feel fuller and this helps to reduce your intake of carbohydrates, improving blood glucose control.

Foods high in fat and/or sugar: Foods such as cakes, biscuits, chocolate and fizzy drinks will increase your blood glucose levels very quickly and for that reason they should generally be avoided by people with gestational diabetes. Choose sugar-free squash and fizzy drinks.

Which foods make my glucose rise?

Take care with your choice of starchy foods

When choosing starchy foods, choose higher fibre options and watch your portion sizes.
Starchy foods: such as potatoes, rice, pasta, bread and cereals provide you with slower release energy so they should be included at each meal.

Will these foods increase my blood glucose levels?

Starchy foods are digested into glucose at varying rates. The measure of this rate is known as the glycaemic index (or GI).

The foods which digest more slowly have a low GI value, so are ideal for keeping blood glucose levels steady. Foods which digest quickly have a higher GI value, causing a more sudden peak in blood glucose level. It is better to replace them with lower GI options.

Portion size guidance

Low GI starchy foods include: (aim for less than 30g of carbohydrate)

• New and boiled potatoes – approximately the size of two to three eggs
• Sweet potatoes – approximately the size of two to three eggs
• Porridge or oat cereals 30–40g
• Nut-based muesli (no added sugar) 30–40g
• Special K (original), Branflakes, All-Bran, Shredded Wheat or Weetabix 40g
• White or wholemeal pasta or noodles (cooked) three to four tablespoons or 50g (dry weight)
• Wild rice or white or brown basmati rice three to four tablespoons or 50g (dry weight)
• Any beans, lentils or pulses (these have very little effect on blood glucose)
• Breads: Granary, seeded rye and multigrain one to two slices
• Pitta bread or wrap (wholemeal) – one

The picture book and app ‘Carbs and Cals’ will help you with 30g carbohydrate portions. Visit the carbs and cals website. (Opens in a new window)

Lower carbohydrate breads include: (Carbohydrate/Portion)

• Livlife with half the carbs Seriously Seeded: 3.8g/slice – Waitrose, Ocado and selected Co-op
• Hi-Lo Loaf: 5g/slice – Sainsbury’s and Ocado
• Genius Protein Punch Gut-Lovin’ COB: 15g/100g – Sainsbury’s, Tesco and Ocado
• Hovis lower carb breads (wholemeal/seeded): 9.8g/9.9g per slice – Asda, Morrisons and Ocado
• Burgen Soya and Linseed**: 11.8g/slice – Tesco, Asda, Sainsbury’s, Morrisons, Waitrose, Ocado, Co-op and Iceland
• Tesco Finest High Protein: 10g per slice – Tesco

** We like this one as it is supplemented with calcium and provides Omega-3 (great for you and baby)

Mini wraps contain about 15g carbs

Cut down on food and drinks containing sugar

Cut down on these as they can make your blood glucose level rise quickly

• Sugar, glucose, dextrose. Avoid adding these to tea and coffee.
• Fizzy drinks, squashes, cordials, fruit juices and smoothies.
• Honey, jam, marmalade, lemon curd, syrup, treacle.
• Sweets, chocolate and chewing gum.
• Drinking chocolate and malted milk drinks (such as Horlicks, Ovaltine).
• Chocolate and cream biscuits.
• Breakfast cereals coated with sugar, honey or chocolate.
• Sweet puddings such as crumble, trifle, cheesecake.
• Summer sweet treats with less than 10g of carbohydrate.

Low sugar alternatives that you may wish to try instead

• Artificial sweeteners are safe during pregnancy: aspartame (Canderel, Hermasetas); saccharin (Sweetex); Acesulfame potassium; Sucralose; Stevia.
• Sugar-free drinks (diet or zero drinks); no added sugar squashes.
• Marmite, Bovril, wholegrain no added sugar peanut butter.
• Sugar-free sweets (one or two) are fine occasionally but avoid ‘diabetic’ sweets and chocolates.
• Cocoa made with milk and sweetener, low sugar instant drinks such as Options or Highlights.
• Plain or wholegrain biscuits such as digestives, Hobnobs, Rich Tea, Garibaldi, oatcakes, breadsticks, crispbreads and crackers (one or two only).
• Wholegrain cereals such as porridge: use whole oats (such as Mornflakes /Jumbo Oats), Shredded  Wheat, Shreddies, Bran flakes and Weetabix (see portion guidance on page 8)
• Try sugar-free jelly; a small slice of low sugar homemade teacake/loaf (see Diabetes UK website for recipe); low sugar yoghurts or fromage frais (for example: Weight Watchers; Activia 0%; any 0% or diet yoghurt; Danone Light and Free; Muller Light may be suitable) – but consider the portion size
  when you are eating these foods.
• Twister Mini lollies, Mini Milk lollies and Claudi & Fin Frozen Yoghurt lollies, Gruffalo Ice Tusks, Fab Mini, Jude’s Lower Calorie Chocolate Minis.

Do some physical activity every day

Regular activity, as part of your daily routine will help you to control your blood glucose levels. Moderate exercise is recommended but just moving more will help, so any additional movement will help your post-meal blood glucose levels. It also provides other health benefits.

The most effective time for activity is after meals.

For more guidance see: Recreational exercise and pregnancy: information for you (Royal College of Obstetricians and Gynaecologists) at www.rcog.org.uk (Opens in a new window)

Do I need nutritional supplements?

Yes.  There are two vitamins needed during pregnancy: folic acid and vitamin D. Those who follow a vegetarian / plant based diet may need additional supplementation of iodine, omega-3 fatty acids and vitamin B12.  If you are following a plant-based diet please request advice from a dietitian.

For more guidance visit The British Dietetic Association pregnancy diet webpage. (Opens in a new window)

Folic acid: You should take 400 mcg supplement daily before and up to the 12th week of pregnancy as well as eating a folate rich diet (green vegetables, fortified breads and cereals). This is to help prevent neural tube defects (NTD). Some people need to take a higher dose of Folic Acid (see NHS information for further guidance on those who you should take a 5 mg dose or discuss this at your antenatal appointment.

Vitamin D: A supplement of 10mcg/400iu every day throughout pregnancy and when breastfeeding.  Those with higher risk of deficiency (those with a pre-pregnancy BMI.30, those with increased skin pigmentation and reduced exposure to sun-light) need to take a higher Vit D provision of 25mcg/1000iu (do not exceed 100mcg / 4000iu).  Vitamin D helps to adsorb calcium and is important for bone health; too little can cause rickets in your baby.  Many, but not all, pregnancy multivitamins contain the recommended amount of vitamin D, so do check the label. Healthy start vitamins (free for eligible women) contain vitamin D.

Iodine: a higher requirement of iodine is required if you are planning a pregnancy, pregnant or lactating.  If you are eating a healthy, balanced diet that contains milk, dairy products and fish, your requirements are likely to be met. If you are vegan or have a compromised nutritional intake it is recommended to take a supplement of 150mcg daily (this is included in most pregnancy multivitamins – check the label).  If you have an existing thyroid condition request advice from your GP / dietitian.

Multivitamins – use a pregnancy multivitamin as standard multivitamins contain too much vitamin A.

Why do my blood glucose levels fluctuate when I eat the same meals?

You may notice your blood glucose levels fluctuate day to day. This may be due to varying amounts of exercise and/or hormones in the body.

Am I at risk of developing diabetes after my pregnancy?

Following the birth, gestational diabetes usually goes away. However, up to 50% of women who had gestational diabetes in pregnancy will develop type 2 diabetes in the future.
The best ways to significantly lower your risk are through weight loss and making dietary modifications and lifestyle changes:

• being more active
• choosing lower GI foods
• eating a healthy balanced diet.

If you would like further support with this after the birth of your baby, please ask to be referred to a dietitian.

Below are a few suggestions to get you started:

• Breastfeed your baby, if possible. Exclusive breastfeeding for more than two months helps with post- delivery weight loss. It may lower the child’s risk of being overweight or obese, which is a risk factor
  for type 2 diabetes.
• Reach your pre-pregnancy weight 6 to 12 months after your baby is born. Then, if still overweight, work to lose at least 5 to 7% of your body weight slowly, over time, and keep it off.
• If you feel you need additional support with reducing your weight, you can discuss this with your midwife or ask your GP to refer you to a dietitian.
• Make healthy food choices such as fruits and vegetables, fish, lean meats, dry beans and peas, lentils, whole grains, and low-fat or skimmed milk and cheese. Choose water to drink.
• Eat smaller portions of food to help reach and stay at a healthy weight.
• Be active at least 30 minutes, five days per week to help burn calories and lose weight.
• Help your children lower their risk of developing type-2 diabetes by making healthy food choices, being physically active at least 60 minutes a day, and staying a healthy weight.
• Encourage the whole family to follow a healthy lifestyle and stay at a healthy weight by eating small portions of healthy foods and moving around more – if the whole family does this it is a lot easier and the results are much more effective.

Foods to avoid or be careful with (Source: BDA – Opens in a new window)

Take extra care with the following listed in the table due to their possible risks to your baby.

Risk: Salmonella.
Avoid: Raw shellfish; Raw and undercooked meats; Unpasteurised milk; Raw or undercooked eggs without the Lion Code.
Take care: Processed ice-cream made with pasteurised milk and eggs (i.e. from the supermarket) should be safe. UK eggs with the Lion Code can be served raw or lightly cooked.

Risk: Listeria.
Avoid: Soft ripened cheeses including Brie, Camembert and some goat’s cheeses; Blue veined cheeses e.g. Danish Blue; All unpasteurised dairy products; All types of pâte; Soft serve ice cream from vans or kiosks.
Take care: Ensure takeaway and cooked-chill ready meals are heated thoroughly and piping hot.

Risk: Contaminants (eg mercury, dioxins)
Avoid: Shark; Marlin; Swordfish
Take care: Limit tuna to four medium cans per week or two steaks. Eat oily fish, e.g. salmon, mackerel, sardines, no more than twice per week.

Risk: Vitamin A
Avoid: Multivitamin supplements containing excess retinol form of vitamin A; Fish liver oils containing more than 700mcg/day; Liver and liver products e.g. pate, faggots.

Risk: Caffeine
Avoid: Foods labelled high caffeine content
Take care: Have no more than 200mg caffeine daily. No more than two mugs of instant coffee (one mug of filter coffee) or three cups of tea a day. Or choose decaffeinated. Other foods containing caffeine include cola, high energy drinks and chocolate.

How can I prevent constipation?

Eat wholemeal bread, high-fibre breakfast cereal, fruit and vegetables and drink plenty of water daily.

Alcohol in pregnancy

UK guidelines recommend that for those planning pregnancy and those who are pregnant, the safest option is to avoid alcohol. Alcohol can increase the risk of miscarriage or your baby could develop a group of problems known as Foetal Alcohol Spectrum Disorder which include poor growth and learning and behavioural difficulties. If you have any concerns about alcohol consumption in pregnancy, speak to your midwife. (Source: BDA (Opens in a new window))

Example meal plan

Breakfast

• One small pot of natural/Greek yoghurt (15) topped with chopped fruit (one handful – or berries, or nuts or seeds).
• One or two Weetabix or Shredded Wheat biscuits with 100ml of milk; or
• 30g porridge oats with milk; or 25g jumbo porridge oats soaked overnight in crème fraiche (carb-free) or milk/yoghurt topped with nuts or seeds.
• One or two eggs on one or two  slices of toast.
• One slice of wholewheat toast (15g) with a topping of poached/scrambled eggs, mushroom, tomato, cheese, ham, bacon, avocado.

Snack

• a handful of fruit; or
• 200mls milk; or suitable yoghurt
• a suitable yoghurt.
• Nuts, seeds, cheese or see our snacks booklet

Lunch

• a sandwich with one or two slices of bread, protein and salad (consider using low-carb bread)

Snack

• a piece of fruit; or
• vegetable sticks with hummus; or as suggestions above.

Evening meal

• pasta, rice or potatoes (see suggested portions), protein and vegetables. on page 9

Snack

• as suggestions above.

Drinks

• water; or
• no added sugar or sugar free squash; or
• ‘diet’ or ‘zero’ fizzy drinks.

You can watch a video on You Tube called ‘Healthy Eating for Gestational Diabetes (Opens in a new window)‘

If you have printed this page, activate your smartphone camera and hold it over the QR code below to view the video.

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