Iron in Pregnancy: Why Your Blood Needs a Promotion Here is something nobody tells you clearly enough: during pregnancy, your blood volume increases by approximately 50%. FIFTY PERCENT. You are not just growing a baby. You are growing an entirely new blood supply to go with it. And iron is what makes that blood work. Without enough iron, your body cannot produce adequate haemoglobin — the protein in red blood cells that carries oxygen from your lungs to the rest of your body and, critically, to your baby. Iron-deficiency anaemia in pregnancy is the most common nutritional deficiency in the world. It affects around 40% of pregnant women globally, according to the World Health Organisation. In some regions, that figure is over 50%. It is not a minor inconvenience. Untreated anaemia in pregnancy is associated with preterm birth, low birth weight, maternal fatigue so severe it impairs daily function, and increased risk of haemorrhage after delivery. ## How Much Do You Actually Need Before pregnancy, an adult woman needs 18mg of iron per day. During pregnancy, that requirement rises to 27mg per day — a number that is genuinely difficult to reach through diet alone, which is exactly why iron supplements are included in antenatal care packages in most countries. Your body partially compensates by absorbing iron more efficiently during pregnancy, but this adaptation is not sufficient on its own for most women. ## The Two Types of Iron and Why It Matters Haem iron — found in red meat, poultry, and fish — is absorbed at 15-35% efficiency. Your body takes it up readily and does not require much assistance. Non-haem iron — found in plant foods: spinach, lentils, beans, tofu, fortified cereals — is absorbed at only 2-20% efficiency. It is abundant in the diet of many pregnant women globally, but the low absorption rate means you need significantly more of it to meet your needs. The critical rule for non-haem iron: always pair it with vitamin C. Vitamin C (ascorbic acid) converts non-haem iron into a more absorbable form, roughly tripling its uptake. A squeeze of lemon on lentil soup. Tomatoes with leafy greens. Orange juice with fortified cereal. These combinations are not just pleasant — they are clinically meaningful. ## What Blocks Iron Absorption Tea and coffee — specifically the tannins they contain — bind to iron in the gut and prevent absorption. This is clinically significant. Drinking tea or coffee within one hour of an iron-rich meal or supplement can reduce iron absorption by 60-80%. Calcium also competes with iron for absorption. If you take calcium supplements, take them at a different time of day from your iron supplement. Phytates — found in whole grains and legumes — also reduce iron absorption, though soaking, sprouting, or fermenting these foods (as done in many traditional cuisines globally) significantly reduces phytate content. ## Best Food Sources Haem iron (most bioavailable): - Beef liver: 6.5mg per 85g — the highest food source - Beef, lean: 3mg per 85g - Chicken or turkey: 1-1.5mg per 85g - Oysters: 8mg per 85g (ensure fully cooked) Non-haem iron (pair with vitamin C): - Cooked lentils: 3.3mg per 180g - Cooked kidney beans: 3.9mg per 180g - Spinach: 3.2mg per 180g cooked - Tofu: 3mg per 120g - Fortified breakfast cereal: 4-18mg per serving (check label) - Dark chocolate (70%+): 3.4mg per 28g ## Signs You May Be Anaemic - Unusual tiredness that rest does not fully resolve - Pale skin, pale inner eyelids, pale nail beds - Shortness of breath on mild exertion - Rapid heartbeat - Dizziness - Difficulty concentrating If you have these symptoms, tell your midwife or health worker. A full blood count (FBC) is a standard antenatal test and will confirm your haemoglobin level. Do not self-diagnose or self-treat with high-dose supplements without medical guidance — iron overload is also a medical problem. ## Your Iron Supplement If prescribed an iron supplement (ferrous sulfate is the most common), take it on an empty stomach with a glass of orange juice for maximum absorption. The main side effects are constipation and dark stools — both normal, not alarming. If constipation is severe, speak to your midwife about switching to a gentler form (ferrous gluconate or ferrous bisglycinate causes fewer GI symptoms).

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Foods to Avoid in Pregnancy: The Complete No-Nonsense List

Raw fish, soft cheese, deli meat — a clear, medically grounded explanation of what to avoid and exactly why, with no unnecessary panic.

5 min read

Iron in Pregnancy: Why Your Blood Needs a Promotion Here is something nobody tells you clearly enough: during pregnancy, your blood volume increases by approximately 50%. FIFTY PERCENT. You are not just growing a baby. You are growing an entirely new blood supply to go with it. And iron is what makes that blood work. Without enough iron, your body cannot produce adequate haemoglobin — the protein in red blood cells that carries oxygen from your lungs to the rest of your body and, critically, to your baby. Iron-deficiency anaemia in pregnancy is the most common nutritional deficiency in the world. It affects around 40% of pregnant women globally, according to the World Health Organisation. In some regions, that figure is over 50%. It is not a minor inconvenience. Untreated anaemia in pregnancy is associated with preterm birth, low birth weight, maternal fatigue so severe it impairs daily function, and increased risk of haemorrhage after delivery. ## How Much Do You Actually Need Before pregnancy, an adult woman needs 18mg of iron per day. During pregnancy, that requirement rises to 27mg per day — a number that is genuinely difficult to reach through diet alone, which is exactly why iron supplements are included in antenatal care packages in most countries. Your body partially compensates by absorbing iron more efficiently during pregnancy, but this adaptation is not sufficient on its own for most women. ## The Two Types of Iron and Why It Matters Haem iron — found in red meat, poultry, and fish — is absorbed at 15-35% efficiency. Your body takes it up readily and does not require much assistance. Non-haem iron — found in plant foods: spinach, lentils, beans, tofu, fortified cereals — is absorbed at only 2-20% efficiency. It is abundant in the diet of many pregnant women globally, but the low absorption rate means you need significantly more of it to meet your needs. The critical rule for non-haem iron: always pair it with vitamin C. Vitamin C (ascorbic acid) converts non-haem iron into a more absorbable form, roughly tripling its uptake. A squeeze of lemon on lentil soup. Tomatoes with leafy greens. Orange juice with fortified cereal. These combinations are not just pleasant — they are clinically meaningful. ## What Blocks Iron Absorption Tea and coffee — specifically the tannins they contain — bind to iron in the gut and prevent absorption. This is clinically significant. Drinking tea or coffee within one hour of an iron-rich meal or supplement can reduce iron absorption by 60-80%. Calcium also competes with iron for absorption. If you take calcium supplements, take them at a different time of day from your iron supplement. Phytates — found in whole grains and legumes — also reduce iron absorption, though soaking, sprouting, or fermenting these foods (as done in many traditional cuisines globally) significantly reduces phytate content. ## Best Food Sources Haem iron (most bioavailable): - Beef liver: 6.5mg per 85g — the highest food source - Beef, lean: 3mg per 85g - Chicken or turkey: 1-1.5mg per 85g - Oysters: 8mg per 85g (ensure fully cooked) Non-haem iron (pair with vitamin C): - Cooked lentils: 3.3mg per 180g - Cooked kidney beans: 3.9mg per 180g - Spinach: 3.2mg per 180g cooked - Tofu: 3mg per 120g - Fortified breakfast cereal: 4-18mg per serving (check label) - Dark chocolate (70%+): 3.4mg per 28g ## Signs You May Be Anaemic - Unusual tiredness that rest does not fully resolve - Pale skin, pale inner eyelids, pale nail beds - Shortness of breath on mild exertion - Rapid heartbeat - Dizziness - Difficulty concentrating If you have these symptoms, tell your midwife or health worker. A full blood count (FBC) is a standard antenatal test and will confirm your haemoglobin level. Do not self-diagnose or self-treat with high-dose supplements without medical guidance — iron overload is also a medical problem. ## Your Iron Supplement If prescribed an iron supplement (ferrous sulfate is the most common), take it on an empty stomach with a glass of orange juice for maximum absorption. The main side effects are constipation and dark stools — both normal, not alarming. If constipation is severe, speak to your midwife about switching to a gentler form (ferrous gluconate or ferrous bisglycinate causes fewer GI symptoms).

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