All diets / Pregnancy and breastfeeding

Drawing for Pregnancy and breastfeeding: the healthen mark with the word PREGNANCY, beans, orange, cheese, spinach, glass of milk, rye bread and salmon.
What you eat on pregnancy and breastfeeding: beans, orange, cheese, spinach and glass of milk.

Eating in pregnancy and breastfeeding: you're not eating for two. You're eating for one, very carefully.

Pregnancy isn't the time to diet, fast or detox. It's the time to eat well, take two cheap supplements and learn a short list of foods to skip. Here's the list, without the scaremongering.

The short version

What it is
Normal healthy eating, a little more of it later on, plus folic acid and vitamin D, minus a short list of risky foods.
Good for
Your baby's development, your own energy and recovery, and making breastfeeding easier.
Bad at
Weight loss. Not the time. Not the goal.
Evidence
Strong. Folic acid is one of the best-proven things in all of nutrition.
Our take
No fasting, no low-carb experiments, no detoxes. Real food, two supplements, a midwife who knows you.

What a pregnancy diet actually is

It's not a special diet. It's ordinary good eating with three twists: you add two supplements, you cut a few foods that carry an infection or toxin risk, and you eat a bit more in the later months and while breastfeeding.

The rules below follow the NHS and the European Food Safety Authority (EFSA). Your country may differ in the details, and your midwife or doctor always wins over this page.

How it works in your body

In the first weeks, often before you know you're pregnant, the baby's spine and brain start forming from a structure called the neural tube. Folate (vitamin B9) is critical for it to close properly. That's why folic acid matters before pregnancy, not after the test turns positive.

Energy needs barely change at first. EFSA estimates the extra need at roughly 70 kcal a day in the first trimester, 260 in the second and 500 in the third, and about 500 a day while exclusively breastfeeding.6 For scale: 260 kcal is a yoghurt with fruit and a handful of nuts. Not a second dinner.

Your immune system also shifts during pregnancy, which makes some food infections more dangerous, listeria in particular. That's where most of the "avoid" list comes from.

Breastfeeding is the hungrier phase. Making milk takes energy, which is why the extra need is bigger than in most of pregnancy.6 Most of the pregnancy food rules relax after birth: soft cheese, rare steak and sushi are back. Keep taking 10 micrograms of vitamin D a day,2 keep caffeine moderate (it reaches the milk),5 drink to thirst, and keep a glass of water and a proper snack within reach of where you feed. This isn't the moment for a weight-loss diet either: slow, natural change beats a crash diet that leaves you exhausted.

What you eat, what you don't

Eat

  • Vegetables, fruit, beans and lentils, lots
  • Wholegrains: oats, brown rice, wholegrain bread
  • Protein: well-cooked meat, chicken, eggs, tofu, beans
  • Oily fish like salmon or sardines, up to 2 portions a week
  • Pasteurised milk, yoghurt and hard cheese
  • Peanuts and nuts, unless you're allergic

Forget it

  • Alcohol
  • Liver, liver pâté, cod liver oil, vitamin A supplements
  • Shark, swordfish, marlin; raw fish and raw shellfish
  • Unpasteurised milk; uncooked mould-ripened or soft blue cheese
  • Raw or undercooked meat; cold cured meats unless cooked
  • Game meats like pheasant and venison

That list is from the NHS.1 Tuna is limited to four cans or two steaks a week because of mercury, and raw or runny eggs are only fine in the UK if they carry the British Lion stamp. Elsewhere, cook them well.1

Alcohol in pregnancy and breastfeeding

Alcohol is out during pregnancy: there's no known safe amount, and the NHS advises avoiding it completely.1 While breastfeeding, ask your midwife before drinking anything. Our alcohol guide covers the rest of life.

What it's good for, with proof

Folic acid prevents serious birth defects

This is as close to certain as nutrition gets. A large British trial in 1991 showed that folic acid cut the risk of a repeat neural tube defect, like spina bifida, by about 70%.4 A Cochrane review pooling trials found daily folic acid around conception lowered the risk of these defects by about two-thirds.3 The NHS advice: 400 micrograms a day from when you start trying (ideally three months before) until week 12, and a higher 5 mg dose on prescription for people at higher risk, such as those with diabetes or on certain epilepsy medicines.2

Vitamin D for bones, yours and theirs

The NHS recommends 10 micrograms of vitamin D a day from October to March, and all year for people who rarely get sun on their skin, cover up outdoors, or have darker skin. Don't go above 100 micrograms a day.2

Fish: the good outweighs the scary

In a large British cohort, children of mothers who ate less than about 340 g of seafood a week in pregnancy were more likely to have lower verbal IQ and behaviour problems.7 Observational, so not proof of cause. But it's a good reason not to drop fish out of mercury fear. Pick lower-mercury fish and stick to the limits.

The uncomfortable truth

"You're eating for two now." You're not. For most of pregnancy the extra need is small, and in the first trimester close to nothing.6 Eating for two mostly means gaining weight that's hard to lose later.

"Avoid peanuts in pregnancy so the baby won't get allergies." Old advice, now dropped. The NHS says peanuts are fine in pregnancy unless you're allergic or told otherwise.1 In babies at high risk, a large trial found that introducing peanut early in the first year cut peanut allergy dramatically.8 Talk to your health visitor or doctor before trying that at home.

"Coffee is banned." It isn't. EFSA concluded that up to 200 mg of caffeine a day in pregnancy doesn't raise safety concerns for the baby.5 That's about two mugs of instant coffee. Remember tea, cola and energy drinks count too.1

The risks

Allergies: watch the staples

StapleAllergen (EU list of 14)9Swap
Milk, yoghurt, hard cheeseMilkCalcium-fortified soy or oat drink
Well-cooked eggsEggsTofu, beans, meat
Salmon, sardinesFishAlgae-based omega-3 (ask first), walnuts, flax
Wholegrain bread, oatsCereals containing glutenBrown rice, quinoa, buckwheat
Peanuts, peanut butterPeanutsSunflower seed butter
Tofu, soy drinkSoyLentils, chickpeas

Don't do pregnancy eating without your midwife or doctor if you…

  • have diabetes, including gestational diabetes
  • have had a baby with a neural tube defect before
  • take epilepsy medication or other long-term medicines
  • are vegan or have food allergies
  • have had weight-loss surgery
  • have ever had an eating disorder

Healthen me asks about all of these and gives you a different plan if any apply.

How we use pregnancy eating in your plan

If you tell us you're pregnant or breastfeeding, you're screened out of every fasting and low-carb element. No eating windows, no Rebel Day fasting the day after, no keto first meal.

You get a gentle plan instead: three regular meals, the NHS list of foods to avoid built into every recipe, oily fish within the limits, and plenty of plants in the style of the Mediterranean diet. If you have allergies, our allergen-free filters apply on top. And every page reminds you that your midwife beats our app.

This article is general information, not medical advice. If you have a medical condition or take medication, talk to your doctor before changing how you eat.

Sources

  1. NHS. Foods to avoid in pregnancy. Accessed November 2026. www.nhs.uk/pregnancy/keeping-well/foods-to-avoid
  2. NHS. Vitamins, supplements and nutrition in pregnancy. Accessed November 2026. www.nhs.uk/pregnancy/keeping-well/pregnancy-vitamins-and-supplements
  3. De-Regil LM et al. Effects and safety of periconceptional oral folate supplementation for preventing birth defects. Cochrane Database of Systematic Reviews 2015;(12):CD007950. doi.org/10.1002/14651858.CD007950.pub3
  4. MRC Vitamin Study Research Group. Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. Lancet 1991;338(8760):131–137. pubmed.ncbi.nlm.nih.gov/1677062
  5. EFSA Panel on Dietetic Products, Nutrition and Allergies. Scientific Opinion on the safety of caffeine. EFSA Journal 2015;13(5):4102. doi.org/10.2903/j.efsa.2015.4102
  6. EFSA Panel on Dietetic Products, Nutrition and Allergies. Scientific Opinion on Dietary Reference Values for energy. EFSA Journal 2013;11(1):3005. doi.org/10.2903/j.efsa.2013.3005
  7. Hibbeln JR et al. Maternal seafood consumption in pregnancy and neurodevelopmental outcomes in childhood (ALSPAC study): an observational cohort study. Lancet 2007;369(9561):578–585. doi.org/10.1016/S0140-6736(07)60277-3
  8. Du Toit G et al. Randomized trial of peanut consumption in infants at risk for peanut allergy (LEAP). New England Journal of Medicine 2015;372(9):803–813. doi.org/10.1056/NEJMoa1414850
  9. Regulation (EU) No 1169/2011 on food information to consumers, Annex II (the 14 allergens). eur-lex.europa.eu/eli/reg/2011/1169/oj