Anaemia (low iron levels) in pregnancy & iron tablets

Many ladies are diagnosed with low iron levels during pregnancy and are then prescribed iron tablets. Iron is important in pregnancy to support fetal growth and development,  for the expansion of maternal red blood cells and to cover the iron which is lost due to bleeding during birth.

Pregnancy can increase iron requirements by up to 10 times due to demands of the baby, increased blood volume in the mother and blood loss at delivery.

Women from ages 19 to 50 need to intake approximately 15 mg of iron per day, but for a pregnant woman this can increase to 27 mg​1​

Iron rich foods

There are two forms of dietary iron, heme and nonheme. Heme iron is derived from animals, found in foods such as red meats, fish, and poultry. The body absorbs the most iron from heme sources. Most nonheme iron is from plant sources.

Iron rich foods which can be incorporated into a GD diet include the following (iron shown per 100g)​2​:

  • Pumpkin seeds, 15mg
  • Sesame seeds, 10.4mg
  • Mussels, 6.8mg
  • Sunflower seeds, 6.4mg
  • Cashew nuts, 6.1mg
  • Coconut, 4mg
  • Lentils, 3.7mg
  • Red meat (beef), 3.6mg
  • Hazelnuts, 3.2mg
  • Almonds, 3mg
  • Sardines, 2.9mg
  • Walnuts, 2.9mg
  • Brazil nuts, 2.5mg
  • Dark chocolate, 2.5mg
  • Eggs, 2.2mg
  • Peanut butter & peanuts, 2.1mg
  • Pecans, 2mg
  • Chickpeas, 2mg
  • Curly kale, 2mg
  • Kidney beans, 2mg
  • Lamb, 1.8mg
  • Mushrooms, 1.7mg
  • Spinach, 1.6mg
  • Butter beans, 1.5mg
  • Brussels Sprouts, 1.4mg
  • Tofu, 1.2mg
  • Prawns, 1.1mg
  • Tuna, 1mg
  • Broccoli, 1mg
  • Mackerel, 0.8mg
  • Pork, 0.7mg
  • Chicken, 0.7mg
  • Bacon, 0.6mg
  • Salmon, 0.4mg

Do iron tablets impact blood glucose levels?

Iron tablets themselves do not cause raises in blood glucose levels, but you have to be careful what you take them with.

To help iron absorption, many health care professionals will advise to take the iron tablets with vitamin C​3​.​4​ Therefore, it is commonly advised to take the tablet with pure orange juice.

iron tablets and orange juice

Bearing in mind that orange juice has high amounts of fructose (natural sugar) and is used for insulin controlled diabetics to raise blood sugar levels rapidly, within 15 minutes when having hypos, it is strongly advisable to avoid using orange juice to take iron tablets when you have diabetes.

Eating an orange would be preferable over drinking juice as the fibrous flesh and pith will take slightly longer to process.

However, oranges and citrus fruits like clementines are still not tolerable for many mothers with gestational diabetes and so alternative sources of vitamin C are required.

Another point to note, is that you should avoid drinking tea with your iron tablet as the tannin (a polyphenol) in tea, inhibits iron absorption​5​ as well as dairy products such as yogurt, milk, cream and cheese​6​.

Alternative Vitamin C sources

Did you know, there’s lots of foods which contain more vitamin C than oranges?

Strawberries, kiwis, peppers (especially red peppers), broccoli, leafy green vegetables and cauliflower all contain high or good amounts of vitamin C.

I’m not suggesting you eat a lump of broccoli for breakfast, but perhaps strawberries or kiwi with mixed nuts and seeds, or a red pepper diced into an omelette would be a good breakfast for you to try and also helps the iron tablet absorption.

Effervescent Vitamin C supplements

Another option is to take iron tablets with effervescent vitamin C. These vitamin C tablets are immersed in water to fizz and dissolve. Check the ingredients on the label for added sugar, however the majority contain sweeteners instead of sugar, making them a suitable choice which should not raise your blood glucose levels. You can purchase effervescent vitamin C tablets in most shops and Pharmacies and there are a range of flavours and branded ones like Berocca, or stores own brand.

Berroca tablets

No Added Sugar Ribena

No added sugar Ribena is not sugar or carb free but it contains added vitamin C, with 80mg vitamin C per 250ml serving and 1.8g of carbs (the equivalent of just under half a teaspoon of sugar), therefore some women use this to take their iron tablets. However it should be noted that no added sugar Ribena contains aspartame, an artificial sweetener which some would prefer not to have.

Ribena no added sugar

Spatone iron supplementation

Another commonly used product used for iron levels is Spatone.

If you don’t like the taste then you could try drinking it in diet, zero, sugar free carbonated drinks.



Iron tablets can often cause constipation. If you find you are struggling with constipation, please check out this link which will provide some gestational diabetes friendly remedies.

constipation and gestational diabetes


  1. 1.
    SACN Iron & Health Report. Public Health England. Published February 25, 2011. Accessed February 10, 2020.
  2. 2.
    Food Fact Sheet: Iron. BDA: Food Fact Sheet. Published 2021. Accessed April 23, 2021.
  3. 3.
    Hurrell R, Egli I. Iron bioavailability and dietary reference values. The American Journal of Clinical Nutrition. Published online March 3, 2010:1461S-1467S. doi:10.3945/ajcn.2010.28674f
  4. 4.
    Hallberg L, Hulthén L. Prediction of dietary iron absorption: an algorithm for calculating absorption and bioavailability of dietary iron. The American Journal of Clinical Nutrition. Published online May 1, 2000:1147-1160. doi:10.1093/ajcn/71.5.1147
  5. 5.
    Zijp IM, Korver O, Tijburg LBM. Effect of Tea and Other Dietary Factors on Iron Absorption. Critical Reviews in Food Science and Nutrition. Published online September 2000:371-398. doi:10.1080/10408690091189194
  6. 6.
    Hallberg L, Brune M, Erlandsson M, Sandberg AS, Rossander-Hultén L. Calcium: effect of different amounts on nonheme- and heme-iron absorption in humans. The American Journal of Clinical Nutrition. Published online January 1, 1991:112-119. doi:10.1093/ajcn/53.1.112