Gaining weight during pregnancy is both natural and essential. But limiting the weight gained during pregnancy to a healthy amount is a whole other story, and the old adage “eating for two” certainly doesn’t help.

Women may think that “being pregnant gives them the license to eat anything,” said Katherine Tallmadge, a registered dietitian and an op-ed contributor to Live Science. But gaining too much weight during pregnancy can have long-term health consequences for moms, she said.

That’s because it can be really, really hard to lose that extra fat after delivering, she said.

Indeed, studies show that the amount of weight a woman gains during pregnancy plays a major role in how much she’ll lose after giving birth. [The Best Ways to Lose Weight After Pregnancy]

So, with that in mind, here’s how to gain weight during pregnancy in a healthy way.

300 calories

How to put on weight during pregnancy in a wholesome wayTo gain at the rate of 1 lb. (0.45 kilograms) a week — which is the recommendation for most women in their second and third trimesters — it takes only 300 extra calories a day, on average, Tallmadge told Live Science.

A woman could easily get those extra calories, for instance, by drinking two cups of milk (around 100 calories from fat each) and consuming one extra serving of a complete grain (around 100 calories from fat), Tallmadge said. Adding a serving of yogurt or fatty fish is an excellent idea also, she said. (Girls who are obese or obese before being pregnant are recommended to get significantly less than 1 lb. weekly, so they want even fewer extra calorie consumption.)

In any full case, the approach ought to be about eating nutritious meals, Tallmadge said, noting these guidelines aren’t much not the same as other health guidelines, other than women that are pregnant need more calcium somewhat, iron and folic acid than other parents do. (These will come from a prenatal multivitamin, she added.)

Dr. Jacinda Nicklas, an assistant professor of inner remedies at the University of Colorado Institution of Medicine, explained that women should boost their calories with healthy and balanced fats also, such as for example nuts or avocados, not junk food.

Of course, weight-gain requirements change as pregnancy progresses, with the recommended number of calories increasing with each trimester.

Small meals

Although it’s relatively common for women to gain too much weight in the first trimester, for some, it may actually be difficult to get enough calories later in pregnancy.

During the third trimester, the developing fetus gains a lot of fat, and it’s important for a pregnant woman to consume enough calories for the fetus to do so, said Kathleen Rasmussen, a professor of maternal and child nutrition at Cornell University.

But because of the growing size of the baby, and increasingly limited space in a woman’s midsection, it can be difficult for women to eat large meals later in their pregnancy, Rasmussen told Live Science.

As such, Rasmussen recommends that, unless a woman is eating very-high-calorie foods, she should eat several small meals a day.