Pregnancy is a beautiful and special time when you create a new life.
During this time, your calorie and nutrient requirements increase to support the baby's growth and development.
It's extremely important to eat nutritious, high-quality foods and avoid foods that may harm your baby.
Here is a detailed guide about what to eat during pregnancy.
How Much Should You Eat?
During pregnancy, gaining weight is normal. In fact, it's the best sign that your baby is growing.
Naturally, this means that you'll need to eat a little more than usual. However, eating for two doesn't mean doubling your portions.
During pregnancy your body becomes more efficient at absorbing nutrients from your food, so you don't actually need any extra calories during the first three months (1).
That said, you do need to eat approximately 340 extra calories per day in the second trimester and an extra 450 calories in the third to support your baby's growth (1).
However, stay mindful of your food choices. It's also important not to overeat, since eating too many calories can be just as harmful as not eating enough.
Overeating during pregnancy increases your baby's obesity risk later in life. Excess calories also make you gain more weight than necessary. This can increase your risk of developing diabetes during pregnancy, termed gestational diabetes (2, 3).
High blood sugar levels during pregnancy can even increase the risk of miscarriage, birth defects and brain development problems.
Excess weight gain also makes it more difficult for you to return to a healthy weight once your baby is born. Extra weight can also make it more challenging to give birth to healthy babies in future pregnancies (6, 7, 8).
Bottom Line: Eating a little more during the second and third trimesters is necessary to help your baby grow. However, you should avoid overeating since this can pose several risks to the health of both you and your baby.
Eat Extra Protein
Protein is an essential nutrient for pregnancy. It is necessary for the proper development of the baby's organs and tissues, as well as the placenta.
Protein is also used to build and maintain many of your own tissues, including muscles (9).
During pregnancy, your need for protein increases by about 25 grams per day, per baby, particularly during the second half of pregnancy. This means that mothers carrying twins should aim to eat an extra 50 grams of protein each day (9).
Failing to meet this recommendation can cause problems.
Protein from your muscles will be used to feed the baby, which can leave you feeling weaker. Not eating enough protein can also delay your baby's growth (9).
Vegetarians and vegans should pay particular attention to varying their protein sources to ensure they get all the essential amino acids they need.
Bottom Line: Extra protein is necessary to support your baby's growth, especially during the second half of pregnancy. An extra 25 grams per day, per baby, is usually sufficient.
Eat Enough Carbs and Fiber
Carbs are a source of calories for your body and the main source of energy for your baby.
This is why your daily carb needs are slightly increased during pregnancy (10).
Make sure you eat enough carbs by including carb-rich foods with your meals.
However, skip the bakery aisle and opt for nutritious whole foods instead.
Make sure to get enough fiber by eating plenty of vegetables and getting your carbs from healthy, whole foods.
Bottom Line: Carbs help provide energy for your baby to grow. Make sure you include whole foods that are rich in healthy carbs and fiber.
Eat Good Fats
Fat is essential for a growing baby because it helps with brain and eye development.
It also makes it easier for your body to produce sufficient quantities of sex hormones and absorb fat-soluble vitamins A, D, E and K.
Omega-3 fats, especially docosahexaenoic acid (DHA), seem particularly beneficial for the baby's brain development. They may also reduce the risk of premature births and may prevent postpartum depression (12, 13).
Small amounts of DHA can be made in your body from the essential fat alpha-linolenic acid (ALA). The Institute of Medicine (IOM) recommends pregnant women aim for 1.4 grams of ALA per day (14).
You can meet this recommendation by consuming about 1.5 tablespoons (22 ml) of walnut oil, 1.5 tablespoons (22 ml) of ground flaxseeds, 1 tablespoon (15 ml) of chia seeds, seven walnut halves or 2/3 of a cup (158 ml) of soy nuts per day.
To be on the safe side, pregnant women should consider adding at least 200 mg of DHA to their diets each day, especially during the third trimester. You can easily get this amount by consuming 5 oz (150 g) of fatty fish per week.
Vegetarians and vegans should consider adding a daily DHA supplement made from algae oil.
Bottom Line: Eating enough omega-3 fats, especially DHA, is important during pregnancy. It supports the baby's brain and eye development, while reducing the risk of miscarriage and postpartum depression.
Get Enough Iron and Vitamin B12
Iron is a mineral that your body needs to carry oxygen to its cells, including the cells of your growing baby.
Vitamin B12 is also needed to produce red blood cells and is important for the growth and function of the nervous system.
During pregnancy, your blood volume increases, which increases the amount of iron and vitamin B12 you need to consume each day.
A diet poor in these nutrients can make you extra tired and more likely to catch infections. It also increases the risk that your baby is born prematurely, with birth defects or with a low birth weight (19).
Meat, eggs, fish and seafood all contain good amounts of both of these nutrients.
You can also find iron in legumes, whole grains, nuts, seeds and dried fruit. Certain vegetables also contain good amounts, particularly spinach, asparagus, snow peas, beet greens, kale and green peas.
It's important to note that iron from plant foods is not easily absorbed by the human body. Improve this absorption by avoiding tea or coffee with meals and make sure to eat iron-rich plant foods together with foods high in vitamin C (22).
Therefore, vegetarians and vegans should either add a daily supplement to their diet or make sure to consume a sufficient amount of foods enriched with B12. Examples include some breakfast cereals, nutritional yeast or plant-based milks (26, 27).
Bottom Line: Getting enough iron and vitamin B12 each day is important to sustain your energy levels and health. It is also necessary for the normal growth and development of your baby.
Get Enough Folate
Folate is a vitamin necessary for cell growth, nervous system development and DNA production (28).
It's also important for the formation of the red blood cells used to transport oxygen to cells.
This vitamin is sometimes better recognized by its synthetic name, folic acid. Folic acid is the form commonly used in supplements.
Foods rich in folate include legumes, dark leafy vegetables and wheat germ. In North America and some parts of Europe, white flour is also enriched with folic acid.
Due to the high risk of birth defects, women who don't get enough folate from foods alone should strongly consider taking a supplement that provides 0.6 mg per day.
Bottom Line: Getting at least 0.6 mg of folate or folic acid each day will help prevent anemia and decrease the risk of birth defects.
Get Plenty of Choline
Choline is an essential nutrient for many processes in the body, including your baby's brain development (31).
Bottom Line: Eating enough foods rich in choline is essential for the development of your baby's brain.
Consume Enough Calcium and Vitamin D
In addition, calcium plays important roles in blood clotting and muscle and nerve function.
The recommended intakes of calcium and vitamin D do not increase during pregnancy, but it's essential you consume enough.
Aim to consume 1,000 mg of calcium and 600 IU (15 mcg) of vitamin D each day. This is especially important during the third trimester, which is the period with the greatest bone and teeth growth (35).
If you fall short of these recommendations, your baby may take calcium from your bones. This can increase your risk of developing a bone disease later in life.
In order to get enough calcium, consume calcium-rich foods such as dairy products and calcium-enriched plant milks and orange juice.
Other good sources include calcium-set tofu, legumes and dark leafy vegetables.
Too little vitamin D can increase your risk of developing diabetes and high blood pressure. It can also increase your chances of giving birth to a low-weight baby (39).
Consider eating vitamin D-rich foods or taking a supplement if you live in a place where sun exposure is limited. Also consider a supplement if you have dark skin or rarely get sun without using sunscreen.
Bottom Line: Calcium and vitamin D are nutrients essential for the development of your baby's bones and teeth. Getting enough may also lower your risk of bone disease, cancer, diabetes and depression.
Foods to Eat
In order meet the nutrition recommendations above, aim to include as many of the following foods in your diet as possible:
- Fruits and vegetables: These are great sources of fiber, which helps prevent constipation. They're also high in vitamin C, which increases iron absorption from foods.
- Spinach, wheat germ and beans: These foods are particularly high in folate, which supports the normal development of your baby's nervous system.
- Meat, fish, eggs, nuts and beans: These provide protein and iron. Meat and fish are also good sources of vitamin B12, while eggs and peanuts are great sources of choline.
- Dairy or calcium-enriched dairy alternatives: Milk, cheese, calcium-set tofu or calcium-enriched orange juice or plant milks are all great sources of calcium.
- Salmon, flaxseeds, chia seeds, walnuts and soy nuts: These foods contain omega-3s. Salmon is rich in DHA, which is good for your baby's brain development.
Additionally, make sure to base most of your diet on whole, unprocessed foods. Here is a list of 50 healthy foods to consider.
Bottom Line: Consuming the nutrient-rich foods above will contribute to your health and the healthy development of your child.
Foods to Avoid
Pregnant women are at higher risk of food poisoning, especially from bacteria and parasites such as Listeria, Salmonella and Toxoplasma.
Below are foods you should avoid or consume very rarely during pregnancy.
Soft Cheeses, Deli Meats and Unpasteurized Foods
Avoid soft cheeses, deli meats and unpasteurized dairy products or juices because they can contain several types of bacteria.
Pasteurization is the most effective way to kill these bacteria. So whenever possible, pick foods and drinks that have been pasteurized (43).
Raw or Undercooked Meat, Fish and Seafood
Sometimes, the bacteria can be passed to the unborn baby without causing symptoms for the mother. One example is Listeria, sometimes found in raw fish (51).
Therefore, make sure all meat and fish is cooked properly (55).
Raw Eggs and Sprouts
The danger with Salmonella is that it sometimes causes cramps in the uterus which can lead to premature birth or stillbirth (59).
The surface of unwashed fruits and vegetables can also be contaminated with bacteria and parasites (62).
Toxoplasma is a particularly dangerous parasite that can be found on the surface of fruits and vegetables. Infants infected with this parasite can be born with serious eye or brain damage or may develop blindness or intellectual disabilities later in life (63).
You can reduce your risk of infection by thoroughly washing, peeling or cooking all fruits and vegetables (64).
Mercury is a very toxic element that can be found in polluted water.
Predatory fish that live in polluted oceans can easily accumulate high amounts of mercury.
This is why consuming fish such as shark, swordfish, mackerel, marlin and tuna should be limited during pregnancy.
Organ meats and meat from organs like liver can be high in retinol, an animal form of vitamin A. Too much retinol can harm your unborn baby.
Organ meat and its related food products also contain very high levels of copper, which can result in birth defects and liver toxicity (69).
Too Much Caffeine
Caffeine is easily absorbed by you and passes very quickly to your baby.
Babies exposed to too much caffeine during pregnancy are at higher risk of poor growth. They're also more likely to develop chronic diseases in adulthood, such as type 2 diabetes and heart disease (73, 74, 75).
Since it's difficult to estimate the lowest safe level of intake, the best approach is for pregnant women to avoid alcohol completely.
Low-Calorie Diet Items and Junk Food
To support your baby's growth, your body needs more calories and nutrients.
However, low-calorie “diet" foods lack the extra calories you need.
On the other hand, junk foods may provide too many calories and encourage overeating. This can lead to excess weight gain, which increases the likelihood of birth complications (3).
Finally, both low-calorie diet foods and junk foods lack the nutrients your body needs to support the normal development of your baby.
Certain Herbal Teas
Certain herbal teas should be avoided during pregnancy because they can stimulate uterine contractions and bleeding, increasing the risk of miscarriage (83).
Bottom Line: Pregnant women should be cautious with unpasteurized foods, uncooked meat, raw eggs, unwashed produce, high-mercury fish, organ meat, caffeine, alcohol, junk food and certain herbal teas.
Drink Enough Fluids
Proper hydration is essential for a healthy pregnancy.
Drinking enough water prevents constipation and helps dissolve waste products so they can be more easily flushed through the kidneys.
The recommended fluid intake from beverages during pregnancy is estimated at 10 cups (2.3 liters) per day (87).
To see if you're drinking enough, check the color of your urine. A light color, closer to the color of lemonade than apple juice, is a good sign that you're drinking enough.
Bottom Line: Drinking enough fluids during pregnancy helps prevent premature contractions and decreases constipation, swelling and fatigue.
What About Supplements?
A prenatal multivitamin can be an easy way to supplement your diet during pregnancy.
That being said, most of your nutrients should come from whole foods, with the multivitamin only filling in the gaps.
If you do opt for a multivitamin, make sure to pick one designed specifically for pregnancy, since the nutrient levels will be better adapted to your needs.
Additionally, some health professionals recommend taking a supplement up to three months before conception, especially if your diet is low in folate.
Bottom Line: Prenatal supplements can help you meet your nutrient needs. However, they are not a replacement for a nutritious diet.
Take Home Message
What you eat during pregnancy has a direct and lasting impact on the health and development of your baby.
Since you need more calories and more nutrients, it's important to eat nourishing foods that help you meet your daily requirements.
It's equally important to pay attention to food hygiene, preparing meals in a way that reduces the risk of bacterial and parasite contamination.
This article was reposted from our media associate Authority Nutrition.
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(Left) Candida yeasts live on parts of the human body. Imbalance of microbes on the body can allow these yeasts, some of which are hybrids, to grow and cause infection. (Right) Cryptococcus yeasts, including ones that are hybrids, can cause life-threatening infections in primarily immunocompromised people. Centers for Disease Control and Prevention<p><a href="https://doi.org/10.1371/journal.ppat.1008315" target="_blank">Why certain <em>Aspergillus</em> species are so deadly</a> while others are harmless remains unknown. This may in part be because <a href="https://doi.org/10.1016/j.fbr.2007.02.007" target="_blank">combinations of traits, rather than individual traits</a>, underlie organisms' ability to cause disease. So why then are hybrids frequently associated with human disease? Hybrids inherit genetic material from both parents, which may result in new combinations of traits. This may make them more similar to one parent in some of their characteristics, reflect both parents in others or may differ from both in the rest. It is precisely this mix and match of traits that hybrids have inherited from their parental species that <a href="https://www.nytimes.com/2010/09/14/science/14creatures.html" target="_blank">facilitates their evolutionary success</a>, including their ability to cause disease.</p>