Women have higher protein requirements during pregnancy to support fetal development. Sometimes, getting enough protein is a challenge, and eating protein bars while pregnant can be a convenient way to pack more in. However, some protein bars aren't healthy and could even pose health risks.
Protein bars that are high in sugar or contain caffeine or herbal ingredients should be avoided during pregnancy.
Protein During Pregnancy
Every cell in the human body contains protein. One of the three macronutrients in addition to carbohydrate and fats, protein is responsible for building and repairing all the cells in your body and that of your baby.
Protein plays a crucial role in numerous body processes, including blood clotting, fluid balance, immunity, vision and creation of hormones and enzymes. It's a primary part of skin, hair, nails, muscle, bone and internal organs, and it is also found in nearly all body fluids, according to the Food and Drug Administration.
In addition to supporting your body's own protein needs, you must get enough to support those of your growing fetus. Therefore, during pregnancy, the dietary reference intake established by the Food and Nutrition Board (FNB) of the National Academies of Medicine for women is 71 grams daily, up from the normal average amount for women of 46 grams. The DRI is based on an average of .8 grams of protein per kilogram of ideal body weight.
However, according to an article published in Advances in Nutrition in July 2016, the FNB's recommendation may be not be enough, at least in certain stages of pregnancy. The review authors state that the current DRI doesn't take into account that protein needs change during gestation, increasing for both mother and baby as the pregnancy progresses. Their estimates put actual pregnancy protein needs at 1.2 grams per kilogram of body weight in early pregnancy and 1.52 grams per kilogram in later stages of pregnancy.
Protein Bars While Pregnant
While it's not difficult to get all the protein you need from whole foods, it's not always convenient. If it's a choice between grabbing a donut or muffin from a coffee shop or digging in your bag for a protein bar, definitely go for the bar!
However, don't fall prey to believing that these bars are "health foods" or offer complete nutrition. Protein bars are supplements, and manufacturers make grand claims about their ingredients and benefits. These claims are often overblown or false, but manufacturers can get away with it because the Food and Drug Administration doesn't regulate supplements in the same way it does drugs.
One of the biggest problems with protein bars while pregnant is their sugar content. Protein bars are promoted as healthy alternatives to snack foods, but they can contain as much sugar as a candy bar — or more! For example, one popular brand of protein bar contains 26 grams of sugar per bar, which is more than the 24 grams provided by a candy bar, per USDA data.
Looking at a typical protein bar's ingredients list, it's easy to see where all this sugar comes from. The first ingredient is a proprietary "carbohydrate blend," that is actually just several forms of refined sugar. These are the bars you definitely want to avoid.
But even some bars made with whole food ingredients are still high in sugar. One brand contains blueberry juice concentrate, which is just a concentrated source of sugar, for a total of 17 grams of sugar. This type of bar is a better choice, but still not the best protein source you should be eating on a regular basis.
That's not to say you can't have any sugar when you're pregnant, but excess sugar intake can be harmful to you and your baby in various ways. For example, a study published in June 2018 in the American Journal of Preventive Medicine found that high sugar intake during pregnancy could negatively affect child cognition.
Another study published in 2017 in the European Respiratory Journal concluded that higher sugar intakes during pregnancy were associated with atopy, or the genetic tendency toward developing allergic diseases.
Read more: Best Healthy Protein Bars
Other Protein Bar Problems
Bars may contain other ingredients that pregnant women should avoid, including caffeine. Caffeine crosses the placenta and takes longer to be metabolized in pregnant women, according to authors of a meta-analysis published in Human Reproduction in May 2015. After reviewing data from the Snart-Gravid study involving 5,132 Danish women, the researchers found that higher caffeine intakes in early pregnancy were associated with a higher risk of miscarriage.
Another study in BMC Medicine in February 2013 found that caffeine intake during pregnancy was associated with low birth weight and babies being small for gestational age. In fact, the intake levels at which the risk increased were lower than the generally recommended "safe" levels for pregnant women in the U.S. of 200 milligrams per day, according to the American College of Obstetricians and Gynecologists (ACOG). Caffeine can come from many sources besides coffee, including cocoa, guarana, kola nut, yerba mate and tea, reports the USDA.
Finally, pregnant women are warned to avoid some herbal ingredients in protein bars because their effects haven't been studied in pregnant women. Mayo Clinic even warns women to avoid drinking herbal tea — including those marketed to pregnant women — without a doctor's consent, because there is not enough evidence to say these ingredients are 100 percent safe.
Healthy Snacks for Pregnant Women
Being on the go doesn't necessarily mean you have to rely on protein bars. As often as possible, get your nutrition from unprocessed, fresh whole foods. This includes lean protein from fish, eggs, chicken, beans and low-fat dairy, carbohydrates from whole grains, fruits and vegetables, and healthy fats from nuts, seeds, olive oil and avocado.
It's easy to prepare healthy snacks for pregnant women that are high in protein and convenient to carry with you to work or while running errands. Nuts are a top choice for protein and healthy fats, easy to pack in your purse or even keep in the glove compartment of your car. Hard-boiled eggs, hummus, and carrot sticks and cheese are also portable protein snacks.
You can also make your own homemade pregnancy nutrition bars without too much trouble. This gives you total control over what goes into your snack, and it allows you to focus on ingredients that are not only rich in protein, but also good sources of the other nutrients crucial to a healthy pregnancy, including calcium, iron and folate, according to the ACOG.
For a bar that you don't even have to bake, combine almond butter, flax meal and a natural alternative sweetener such as monk fruit or stevia. Mix it all together, pop it in a pan in the refrigerator and cut into bars when cold. Preparing them in large batches and freezing them until you need them makes for a no-mess, no-stress snacking option.
- Food and Drug Administration: "Protein"
- National Academies of Medicine: "Summary Tables, Dietary Reference Intakes"
- Advances in Nutrition: "Protein and Amino Acid Requirements during Pregnancy"
- USDA: "Basic Report: 19142, Candies, Mounds Candy Bar"
- American Journal of Preventive Medicine: "Associations of Prenatal and Child Sugar Intake With Child Cognition"
- European Respiratory Journal: "Maternal Intake of Sugar During Pregnancy and Childhood Respiratory and Atopic Outcomes"
- American Academy of Allergy, Asthma & Immunology: "Atopy Definition"
- Human Reproduction: "Caffeine and Caffeinated Beverage Consumption and Risk of Spontaneous Abortion"
- BMC Medicine: "Maternal Caffeine Intake During Pregnancy Is Associated With Birth Weight but Not With Gestational Length: Results From a Large Prospective Observational Cohort Study"
- American College of Obstetricians and Gynecologists: "Nutrition During Pregnancy"
- USDA: "Caffeine-Containing Ingredients in Dietary Supplements: Guarana, Kola Nut, Yerba Mate, Tea, and Cocoa"
- March of Dimes: "Foods to Avoid or Limit During Pregnancy"
- Mayo Clinic: "Pregnancy Nutrition: Foods to Avoid During Pregnancy"
- NCBI: American Journal of Public Health: "Too Little, Too Late: Ineffective Regulation of Dietary Supplements in the United States"