Five pregnancy nutrition myths—from food cravings to fish safety—with clear answers.

Should you eat for two? Drink up even if it makes you sprint to the bathroom? It’s time to clear up some common myths about pregnancy nutrition.

Giving in to your cravings, cutting down the number of glasses of water you drink, and taking in too many calories are just a few bits of common “wisdom” you hear when you’re pregnant. Which of these are myths and which are truths?

Pregnancy Nutrition Myths Versus Truths

Myth: “Eating for two” during pregnancy means eating twice as much.

Truth: Most moms-to-be carrying one baby only need about 340 additional calories a day beyond their pre-pregnancy diet in the second trimester—about the amount in 4 ounces of 1 percent milk and half a peanut butter sandwich. In the third trimester, the calorie recommendation increases to 450 extra or the amount in an ounce of cheddar cheese, 8 whole grain crackers, 1 cup of grapes, and 6 ounces of 1% milk. The key: Make sure you’re meeting that number through healthy choices—fruits and vegetables, nonfat yogurt or milk, and lean proteins—instead of empty calories.

Myth: Forget fish during pregnancy because of safety concerns.

Truth: Many kinds of seafood are great sources of docosahexaenoic acid (DHA)—an omega-3 fatty acid that plays an important role in supporting your baby’s developing brain and vision. In fact, experts have updated their pregnancy nutrition recommendations regarding how much seafood pregnant women should include in a healthy pregnancy diet, thanks to its good-for-baby benefits. Worried about mercury intake? Stick with low-mercury choices like salmon and tilapia, which you can enjoy up to twice a week. Steer clear of fish that are high in mercury, like swordfish, mackerel, and shark. Make sure your prenatal supplement and your diet include important DHA. Experts recommend 200 milligrams of DHA per day for pregnant or lactating women.

Myth: Limit water intake to avoid frequent bathroom trips and retaining water.

Truth: While it might be annoying, those frequent bathroom urges are a common pregnancy symptom—due to increasing pressure from your baby on your bladder. But just because you have to hit the ladies’ room regularly doesn’t mean you should cut back on how much water you’re drinking. In fact, pregnant women should be sipping more frequently than their non-pregnant counterparts. That’s because water delivers nutrients to your baby through your blood. How much should you drink? About 10 cups a day—though this also includes liquid intake from other beverages like juice.

Myth: Always give in to pregnancy cravings—they’re your body’s way of letting you know what it needs.

Truth: Whether it’s a cookie or chips, it’s OK to indulge in your favorite treats—in moderation. Just be careful that they’re not edging out healthier choices with nutrients you and your baby need. There’s no evidence to suggest that cravings are a sign of what your body needs, as was previously believed. And if your cravings are for things other than food (such as ice, clay, or sand)—a condition known as pica—discuss it with your doctor.

Myth: All fats are bad for you and should be avoided during pregnancy.

Truth: Many fats are, indeed, not healthy, but it’s smart to stick with good-for-you fats from foods like avocados, nuts, low-mercury seafood, and oils like olive or flaxseed. Fats from omega-3s (a polyunsaturated fat) are an important part of a healthy pregnancy diet for your growing baby, helping with brain development. But while it’s important to get enough of these fats, it’s best to limit (or eliminate) trans fats and limit saturated fats—the kinds that come from foods like butter, French fries, or cookies. Check that your prenatal supplement is helping you reach the daily expert recommended amount of 200 milligrams of DHA, an important omega-3.