During the first trimester, you don’t need any extra calories, but you do need more of specific nutrients that support your baby’s earliest development. The focus should be on nutrient-dense foods, managing nausea, and avoiding a short list of foods that carry real safety risks.
You Don’t Need Extra Calories Yet
One of the most common misconceptions about early pregnancy is that you’re “eating for two” from day one. The CDC is clear on this: the first trimester requires no additional calories. Your body is building the placenta and your baby is still tiny, so your energy needs haven’t meaningfully changed. What has changed is your need for certain vitamins and minerals, which means the quality of what you eat matters far more than the quantity.
Key Nutrients for the First Trimester
Folic Acid
Folic acid is the single most important nutrient in early pregnancy. You need 400 micrograms daily to help prevent neural tube defects, which are serious conditions affecting your baby’s brain and spine. The neural tube forms very early, often before many women even know they’re pregnant, so this one is urgent. Folic acid (the synthetic form of folate, or vitamin B9) is the only form proven to reduce this risk. You’ll find it in prenatal vitamins, fortified cereals, fortified breads, and leafy greens like spinach. Many of the bland comfort foods that appeal during morning sickness, like cereal, crackers, and toast, are actually fortified with folic acid, which is a lucky coincidence.
Choline
Choline is less talked about than folic acid, but it plays a surprisingly large role in the same early developmental window. It supports neural tube formation, brain development, and the creation of neural connections. The recommended intake during the first trimester is 450 milligrams per day. Research suggests that higher choline levels during pregnancy may improve a child’s cognitive function, memory, and attention later in life. Eggs are one of the richest food sources, with two large eggs providing roughly 300 milligrams. Beef liver, chicken, fish, and soybeans are also good sources. Most prenatal vitamins contain little or no choline, so food sources are especially important here.
Iron
Your iron needs in the first trimester are relatively modest compared to later in pregnancy, around 0.8 milligrams of absorbed iron per day. That number jumps to 4 to 5 milligrams in the second trimester and over 6 milligrams in the third, so building good iron habits early helps. Red meat, poultry, beans, lentils, spinach, and fortified cereals are all solid sources. Pairing iron-rich foods with something containing vitamin C (like tomatoes or citrus) helps your body absorb more of it.
Omega-3 Fatty Acids
Your baby’s brain and eye development depend on DHA, a type of omega-3 fat. The goal during pregnancy is about 300 milligrams of DHA daily. The best food sources are low-mercury fish: salmon, sardines, shrimp, pollock, catfish, scallops, and light canned tuna. Two to three servings of these fish per week will typically cover your needs. If you don’t eat fish, a DHA supplement made from algae is an alternative.
Foods to Avoid
The list is shorter than most people expect, but the risks are real. Two concerns drive most of the restrictions: mercury and listeria.
High-mercury fish can damage your baby’s developing nervous system. The fish to skip entirely are shark, swordfish, king mackerel, and tilefish. Stick with the low-mercury options listed above and you’ll get the omega-3 benefits without the risk.
Listeria is a type of bacteria that can cause miscarriage, stillbirth, or serious illness in newborns. It’s particularly dangerous because it can grow even in refrigerated foods. The CDC recommends avoiding unheated deli meats, cold cuts, hot dogs, and fermented or dry sausages unless you heat them until steaming. Soft cheeses made from unpasteurized milk are also a risk. This includes queso fresco, brie, camembert, blue-veined cheese, and similar fresh soft cheeses. Hard cheeses and pasteurized soft cheeses are fine.
Caffeine: How Much Is Safe
You don’t have to give up coffee entirely. The recommended maximum is 200 milligrams of caffeine per day, which works out to roughly two standard cups of coffee. Keep in mind that caffeine also shows up in tea, chocolate, some sodas, and energy drinks, so those count toward your daily total. If your morning sickness has you reaching for ginger ale, check whether it contains caffeine (most don’t, but some do).
Eating Through Morning Sickness
Nausea affects up to 80% of pregnant women in the first trimester, and it can make even thinking about nutrition feel impossible. The good news is that both ginger and vitamin B6 have solid clinical evidence behind them for reducing nausea. Multiple studies have tested around 1 gram of ginger daily (split into smaller doses throughout the day) and found it significantly reduces nausea, retching, and vomiting. Vitamin B6 at various doses has shown similar effectiveness. Many prenatal vitamins include B6, and ginger can come from capsules, ginger tea, or even ginger chews.
Beyond supplements, a few practical strategies help. Cold foods tend to be easier to tolerate than warm ones because they have weaker smells, and strong smells are a common nausea trigger. Bland, starchy foods like crackers, toast, cereal, and bananas are easier on the stomach. Adding peanut butter to a banana or toast is a simple way to sneak in some protein, which helps stabilize blood sugar and may keep nausea from getting worse. Fried and fatty foods take longer to leave your stomach, which tends to make nausea worse, so they’re worth avoiding when you’re feeling queasy.
Eating small amounts frequently, rather than three large meals, is one of the most consistently helpful strategies. Keeping crackers on your nightstand to eat before getting out of bed can head off the wave of nausea that hits many women first thing in the morning.
Staying Hydrated
The general recommendation during pregnancy is 8 to 10 glasses of water per day. In the first trimester, dehydration can sneak up on you if morning sickness involves vomiting. Sipping water throughout the day rather than drinking large amounts at once is usually easier to tolerate. If plain water triggers your nausea, try adding a slice of lemon, drinking it cold, or eating water-rich fruits like watermelon and cucumber. Popsicles and broth-based soups also count toward your fluid intake.
A Practical First Trimester Plate
Putting all of this together, a typical day might look like this: eggs for breakfast (choline and protein), a handful of fortified cereal as a snack (folic acid and iron), a salmon salad for lunch (DHA and protein), fruit and peanut butter in the afternoon, and chicken with spinach and tomatoes at dinner (iron, folate, vitamin C). That combination covers your major nutrient needs without requiring anything exotic or elaborate.
On days when nausea makes that kind of variety impossible, do what you can. A few crackers with peanut butter, a prenatal vitamin, and plenty of fluids will carry you through. The first trimester is temporary, and most women find their appetite and food tolerance improve significantly by weeks 12 to 14.