Prenatal Nutrition: What to Eat (and Avoid) During Pregnancy

Growing a human is the most nutritionally demanding thing your body will ever do. Your baby’s brain, bones, organs, and immune system are all being built from what you eat and drink over the next nine months. But here’s the good news: prenatal nutrition doesn’t have to be complicated. You don’t need a degree in dietetics to eat well during pregnancy — you just need to know the basics.

Let’s break down exactly what your body needs, where to find it, and what to stay away from.

The Essential Nutrients for Pregnancy

Your daily nutrient needs increase during pregnancy, but the old saying “eating for two” is misleading — you really only need about 340 extra calories per day in the second trimester and 450 extra in the third. The first trimester doesn’t require any additional calories at all, according to ACOG guidelines. What matters more than quantity is quality.

Here are the nutrients that deserve your attention:

Folic Acid (Folate)

Why it matters: Folic acid is critical for neural tube development — the structure that becomes your baby’s brain and spinal cord. Adequate folic acid intake significantly reduces the risk of neural tube defects like spina bifida and anencephaly.

How much: ACOG recommends 600 micrograms (mcg) of dietary folate equivalents daily during pregnancy. Your prenatal vitamin should provide at least 400 mcg, and the rest can come from food. Supplementation should ideally begin at least one month before conception.

Where to find it:

Dark leafy greens (spinach, kale, romaine lettuce)
Legumes (lentils, black beans, chickpeas)
Fortified cereals and breads
Asparagus and Brussels sprouts
Citrus fruits and orange juice

Iron

Why it matters: Your blood volume increases by about 45% during pregnancy, and iron is essential for making hemoglobin — the protein in red blood cells that carries oxygen to your baby. Iron deficiency anemia during pregnancy is linked to preterm birth and low birth weight.

How much: The recommended intake during pregnancy is 27 milligrams per day, nearly double the non-pregnant recommendation of 18 mg. Many people need supplemental iron in addition to their prenatal vitamin.

Where to find it:

Lean red meat (one of the most efficient sources of easily absorbed heme iron)
Poultry and fish
Beans, lentils, and tofu
Fortified cereals
Spinach and other dark leafy greens

Absorption tip: Pair iron-rich foods with vitamin C sources (like bell peppers, strawberries, or a squeeze of lemon) to boost absorption. Avoid taking iron supplements with coffee, tea, or calcium-rich foods, as these can reduce absorption.

Calcium

Why it matters: Your baby needs calcium to build strong bones and teeth, to develop a healthy heart, nerves, and muscles, and for blood clotting. If you don’t consume enough calcium, your body will pull it from your own bones to give to your baby.

How much: 1,000 milligrams per day for pregnant adults (1,300 mg for those under 19), according to the National Institutes of Health.

Where to find it:

Dairy products (milk, yogurt, cheese)
Fortified plant milks (soy, almond, oat — check labels)
Calcium-set tofu
Sardines and canned salmon (with bones)
Broccoli and kale

DHA (Omega-3 Fatty Acids)

Why it matters: DHA (docosahexaenoic acid) is essential for your baby’s brain and eye development. Research suggests that adequate omega-3 intake during pregnancy may also reduce the risk of preterm birth.

How much: At least 200 to 300 milligrams of DHA daily, per ACOG guidance.

Where to find it:

Fatty fish (salmon, sardines, herring, anchovies) — aim for 2 to 3 servings per week of low-mercury fish
DHA-fortified eggs
Walnuts and flaxseed (these contain ALA, which your body partially converts to DHA)
DHA supplements (especially important if you don’t eat fish)

Vitamin D

Why it matters: Vitamin D works with calcium to build your baby’s bones and teeth. Deficiency during pregnancy has been linked to preeclampsia and gestational diabetes.

How much: 600 IU per day is the standard recommendation, though many healthcare providers suggest higher amounts. Your doctor can check your levels with a simple blood test.

Where to find it:

Fortified milk and orange juice
Fatty fish
Egg yolks
Sunlight exposure (your body produces vitamin D when skin is exposed to UV rays, though this depends on latitude, season, and skin tone)

Choline

Why it matters: Choline supports brain development and helps prevent certain birth defects. It’s one of the most commonly under-consumed nutrients during pregnancy — many prenatal vitamins don’t contain enough.

How much: 450 milligrams per day during pregnancy.

Where to find it:

Eggs (especially the yolk — one large egg provides about 150 mg)
Lean beef and chicken
Fish
Beans and cruciferous vegetables

Iodine

Why it matters: Iodine is essential for thyroid function, and your thyroid activity increases during pregnancy. Inadequate iodine can affect your baby’s brain development.

How much: 220 micrograms per day during pregnancy, per WHO recommendations.

Where to find it:

Iodized salt
Dairy products
Seafood
Seaweed (in moderation — some varieties contain very high amounts)

What to Eat: Building Your Pregnancy Plate

Rather than fixating on individual nutrients, think about building balanced meals from whole food groups:

Fruits and vegetables (aim for 5+ servings daily): Choose a variety of colors for a wide range of vitamins and minerals. Frozen produce is just as nutritious as fresh and is often more affordable.

Whole grains (6 to 8 servings daily): Brown rice, oats, whole wheat bread, and quinoa provide B vitamins, fiber, and sustained energy. Fiber is especially important for preventing constipation, which is very common during pregnancy.

Protein (aim for 71 grams daily): Your protein needs increase during pregnancy to support your baby’s rapid growth. Good sources include lean meats, poultry, fish, eggs, beans, lentils, nuts, and dairy. If you’re vegetarian or vegan, pay extra attention to combining protein sources throughout the day.

Dairy or calcium-rich alternatives (3 servings daily): Milk, yogurt, and cheese are excellent for calcium. If you’re lactose intolerant or vegan, choose fortified plant-based alternatives.

Healthy fats: Avocados, nuts, seeds, olive oil, and fatty fish. These support your baby’s brain development and help your body absorb fat-soluble vitamins (A, D, E, K).

Foods to Avoid During Pregnancy

Not everything in the fridge is pregnancy-friendly. Here are the key foods to skip and why:

Raw or Undercooked Animal Products

Raw fish and sushi (with raw seafood) — risk of parasites and bacteria
Raw or undercooked eggs — risk of Salmonella. Avoid homemade mayonnaise, mousse, and cookie dough made with raw eggs
Undercooked meat — cook all meat to safe internal temperatures (74°C/165°F for poultry, 71°C/160°F for ground meat)
Raw sprouts (alfalfa, bean, clover) — frequently linked to Salmonella and E. coli outbreaks

High-Mercury Fish

The FDA and ACOG recommend avoiding fish with high mercury levels:

Shark
Swordfish
King mackerel
Tilefish
Bigeye tuna
Marlin

Mercury can damage your baby’s developing nervous system. Stick to low-mercury options like salmon, shrimp, pollock, tilapia, and catfish.

Unpasteurized Products

Unpasteurized milk and juices — risk of Listeria, E. coli, and Salmonella
Soft cheeses made from unpasteurized milk (feta, brie, Camembert, blue-veined cheeses) — risk of Listeria. Pasteurized versions are safe.

Deli Meats and Hot Dogs

Unless heated until steaming hot (74°C/165°F), deli meats and hot dogs can harbor Listeria monocytogenes, a bacterium that can cross the placenta and cause serious complications including miscarriage.

Liver and Excessive Vitamin A

Liver is very high in preformed vitamin A (retinol). Excessive intake — above 10,000 IU per day — has been associated with birth defects. Occasional small portions are generally fine, but avoid eating liver frequently or taking supplements with high doses of retinol.

Alcohol

There is no known safe amount of alcohol during pregnancy, according to ACOG, the CDC, and the WHO. Alcohol crosses the placenta and can interfere with fetal development at any stage, potentially causing fetal alcohol spectrum disorders.

Caffeine

ACOG recommends limiting caffeine intake to less than 200 milligrams per day — roughly equivalent to one 12-ounce (350 ml) cup of brewed coffee. Remember that caffeine is also found in tea, chocolate, soft drinks, and some medications.

Trimester-by-Trimester Nutrition Focus

First Trimester

Your calorie needs don’t change yet, but nutrient quality is crucial. Folic acid is the star nutrient of these early weeks, supporting neural tube closure (which occurs around week 4–6 — often before many people even know they’re pregnant).

If morning sickness is making it hard to eat, don’t panic. Focus on staying hydrated, eat what you can tolerate, and take your prenatal vitamin at whatever time of day it’s easiest to keep down. Check our morning sickness guide for practical coping strategies.

Second Trimester

This is when your baby’s growth really accelerates. You need about 340 extra calories per day — think a banana with almond butter, or a bowl of Greek yogurt with granola. Focus on:

Calcium for bone development
Iron to keep up with your expanding blood volume
Protein for your baby’s rapidly growing muscles and tissues
Omega-3 fatty acids for brain development

Third Trimester

Calorie needs increase to about 450 extra per day. Your baby is gaining weight rapidly — about 200 grams (half a pound) per week in the final months. Key nutrients:

Iron remains critical (many people become anemic in the third trimester)
DHA for continued brain development (the brain grows most rapidly in the third trimester)
Vitamin K for blood clotting (found in leafy greens)
Fiber and water — constipation and heartburn tend to worsen as your baby takes up more space

Special Dietary Considerations

Vegetarian and Vegan Pregnancies

Well-planned vegetarian and vegan diets can absolutely support a healthy pregnancy. Pay special attention to:

Vitamin B12 — found almost exclusively in animal products. Vegans must supplement.
Iron — plant-based iron (non-heme) is less easily absorbed, so aim for higher intake and pair with vitamin C
DHA — consider an algae-based DHA supplement if you don’t eat fish
Protein — combine legumes, grains, nuts, and soy products throughout the day
Zinc and calcium — plan food sources carefully

Discuss supplementation with your healthcare provider. A blood test in early pregnancy can identify any deficiencies before they become a problem.

Gestational Diabetes

If you’re diagnosed with gestational diabetes (typically screened between weeks 24–28), dietary management becomes a central part of treatment. This generally involves:

Spreading carbohydrates evenly across meals and snacks
Pairing carbs with protein and fat to stabilize blood sugar
Choosing complex carbohydrates over refined ones
Monitoring blood glucose levels regularly

Your healthcare team will provide personalized guidance — gestational diabetes is very manageable with the right support.

Food Aversions and Cravings

Pregnancy hormones can make your favorite foods repulsive and make you desperately want things you never normally eat. This is normal. If you’re craving ice cream at midnight, it’s not because your baby “needs” calcium — it’s hormones being hormones.

That said, some cravings for non-food items (ice, dirt, chalk, laundry starch) — a condition called pica — can signal nutritional deficiencies (often iron). If you experience this, tell your doctor.

Hydration Matters

Water is arguably the most overlooked nutrient in pregnancy. Aim for 8 to 12 cups (about 2.3 liters) per day. Adequate hydration:

Helps form amniotic fluid
Carries nutrients to your baby via increased blood volume
Reduces constipation, hemorrhoids, and urinary tract infections
Prevents swelling and overheating

If plain water is unappealing, try adding slices of lemon, cucumber, or berries. Herbal teas (check with your doctor about specific herbs) and water-rich foods like watermelon and cucumber also count toward your intake.

Prenatal Vitamins: A Safety Net, Not a Substitute

Think of your prenatal vitamin as insurance — it covers the gaps, but it shouldn’t replace a balanced diet. Key things to look for in a prenatal:

At least 400 mcg folic acid (ideally 600 mcg or methylfolate)
27 mg iron
200–300 mg DHA
150 mcg iodine
1,000 mg calcium (or supplement separately if not included)
Choline (many prenatals don’t include enough — check the label)

If your prenatal vitamin makes you nauseous, try taking it with food, at bedtime, or ask your doctor about switching brands. A gummy version might be easier on your stomach, though gummies often have less iron.

Frequently Asked Questions

Can I eat sushi during pregnancy?

Sushi made with raw fish should be avoided due to the risk of parasites and bacteria. However, sushi made with cooked seafood (shrimp tempura, crab), vegetables, or smoked salmon that’s been commercially prepared is generally considered safe. When in doubt, opt for cooked options.

How much weight should I gain during pregnancy?

ACOG guidelines for total weight gain based on pre-pregnancy BMI:

Underweight (BMI < 18.5): 12.5–18 kg (28–40 lbs)
Normal weight (BMI 18.5–24.9): 11.5–16 kg (25–35 lbs)
Overweight (BMI 25–29.9): 7–11.5 kg (15–25 lbs)
Obese (BMI ≥ 30): 5–9 kg (11–20 lbs)

These are general guidelines — your provider will give personalized recommendations.

Is it safe to eat spicy food during pregnancy?

Yes. Spicy food is perfectly safe during pregnancy. It won’t harm your baby. However, it may worsen heartburn or indigestion, which are already common in later pregnancy. Eat what you enjoy and adjust based on how you feel.

Should I take additional supplements beyond my prenatal vitamin?

This depends on your individual needs. Common additional supplements during pregnancy include iron (if anemic), vitamin D (if deficient), DHA (if your prenatal doesn’t contain enough), and calcium. Always discuss supplements with your healthcare provider rather than self-prescribing — more isn’t always better, and some nutrients can be harmful in excess.

Can I follow a keto or low-carb diet during pregnancy?

Restrictive low-carb or ketogenic diets are generally not recommended during pregnancy. Your baby’s brain runs primarily on glucose, and ketosis during pregnancy is not well-studied. A balanced diet with complex carbohydrates, protein, and healthy fats is the safest approach. Talk to your doctor before following any restrictive eating pattern during pregnancy.

Sources

American College of Obstetricians and Gynecologists (ACOG). “Nutrition During Pregnancy.” FAQ001, 2022.
ACOG. “Healthy Eating.” FAQ, updated 2023.
World Health Organization (WHO). “WHO Recommendations on Antenatal Care for a Positive Pregnancy Experience.” 2016.
NHS. “Vitamins, Supplements and Nutrition in Pregnancy.” 2024.
U.S. Food and Drug Administration (FDA). “Advice About Eating Fish.” 2024.
National Institutes of Health. “Dietary Supplement Fact Sheets: Iron, Calcium, Folate, Vitamin D.” Office of Dietary Supplements, 2024.
ACOG. “Moderate Caffeine Consumption During Pregnancy.” Committee Opinion No. 462, reaffirmed 2020.