Although you need about 300 extra calories a day especially later in your pregnancy, when your baby grows quickly those calories should come from nutritious foods so they can contribute to your baby's growth and development.
Why it's Important to Eat Well When You're Pregnant
Do you wonder how it's reasonable to gain 25 to 35 pounds (on average) during your pregnancy when a newborn baby weighs only a fraction of that? Although it varies from woman to woman, this is how those pounds may add up:
7.5 pounds: average baby's weight
2 pounds: breast enlargement
7 pounds: your body's extra stored protein, fat, and other nutrients
1.5 pounds: the placenta
2 pounds: enlargement of your uterus
2 pounds: amniotic fluid surrounding your baby
4 pounds: your extra blood
4 pounds: your other extra body fluids
Of course, patterns of weight gain during pregnancy vary. It's normal to gain less if you start out heavier and more if you're having twins or triplets or if you were underweight before becoming pregnant. More important than how much weight you gain is what makes up those extra pounds.
When you're pregnant, what you eat and drink is the main source of nourishment for your baby. In fact, the link between what you consume and the health of your baby is much stronger than once thought. That's why doctors now say, for example, that no amount of alcohol consumption should be considered safe during pregnancy.
The extra food you eat shouldn't just be empty calories it should provide the nutrients your growing baby needs. For example, calcium helps make and keep bones and teeth strong.
While you're pregnant, you still need calcium for your body, plus extra calcium for your developing baby. Similarly, you require more of all the essential nutrients than you did before you became pregnant.