Maternal diet during pregnancy, especially in the third trimester, significantly impacts the developing baby. A balanced third-trimester diet helps mothers avoid complications such as low birth weight, childhood obesity, diabetes, and other chronic conditions.
We recommend maintaining the extra 300 calories incorporated into your diet during the second trimester; no further calorie increase is necessary during the third trimester.
It’s also a good time to simplify your routine with maternity skincare for early pregnancy that supports sensitive, changing skin.
What to Eat in the Third Trimester?
The American College of Obstetricians and Gynecologists (ACOG) emphasises that: “Eating well is one of the best things you can do during pregnancy.” The key is focusing on fats from whole foods rather than the processed saturated and trans fats in packaged foods. Look at this table to determine whether your diet plan for the third trimester of pregnancy is providing enough micronutrients for your body and baby:
| Nutrient | Benefits | Dietary Sources |
| Vitamin A/Beta-carotene |
| Dairy, eggs, fish, carrots, sweet potato, spinach, broccoli, small whole fish |
| Calcium |
| Dairy, green vegetables, sesame seeds, salmon, tofu |
| Magnesium |
| Vegetables, nuts, seeds, seafood, legumes |
| Omega-3 Fatty Acids (DHA) |
| Fatty fish (salmon, mackerel), algal oil |
| Folic Acid |
| Green leafy vegetables (fortified cereals, beans, etc.) |
| Zinc |
| Seafood, lean meats, nuts, and seeds |
| Vitamin D |
| Sunlight exposure, eggs, and fish |
| Iron |
| Red meat, spinach, lentils |
| B Vitamins |
| Lean meats, lentils, and whole grains |
| Iodine |
| Seafood, seaweed, iodised salt |
| Vitamin E |
| Nuts, seeds |
| Vitamin C |
| Citrus fruits, tropical fruits |
In a 2022 study, Am J Obstet Gynecol highlighted that “most women in the United States fail to meet guidelines for nutritious eating and maintaining a healthy weight before and during pregnancy.” The study also recommended that pregnant individuals prioritise improving the quality of their diet rather than increasing their food intake.
Foods to Avoid During the Third Trimester Diet
During the third trimester diet, moms should avoid foods that carry a risk of infection, including:
| Foods to Avoid | Reason | Examples |
| High mercury fish | High mercury fish can affect your nervous system, immune system, and kidneys. It also leads to serious developmental problems in children, with adverse effects even in lower amounts. | Shark, swordfish, tilefish, marlin |
| Raw fish/meat | They may contain bacteria or parasites, which cause dehydration and weakness in the mother. | |
| Processed and deli meat | They can become infected with numerous bacteria during processing or storage. Also, processed meats can have high levels of sodium and unhealthy fats. | Hot dogs, lunch meat, pepperoni, and deli meat |
| Organ meat | Provide essential nutrients, but consuming too much preformed vitamin A may cause congenital malformations and pregnancy loss. Limit intake to a few ounces per week. | Liver, kidney |
| Raw Sprouts | The humid environment for sprouting promotes Salmonella growth. | Alfalfa, clover, radish, mung bean sprouts |
| Unpasteurised Dairy Products | They can contain harmful bacteria like Listeria, Salmonella, E. coli, and Campylobacter. | Raw milk, cheese, yoghurt |
| Processed Foods | These low in nutrients and high in unhealthy fats increases the risk of weight gain, delivery complications, and childhood obesity. | Various packaged and fast foods |
| Alcohol and Caffeine | They increase the risk of pregnancy loss, stillbirth, low birth weight, and developmental issues. | Beer, wine, coffee, tea, cocoa |
Overall, to achieve a balanced third-trimester pregnancy diet:
- Incorporate more fruits, vegetables, and whole foods.
- Emphasise fats sourced from whole foods, such as nuts, seeds, avocados, olive oil, eggs, salmon, lean meats, yoghurt, and cheese.
- Reduce intake of processed high-fat items.
- Avoid raw food, alcohol, and caffeine.
Should I Change My Pregnancy Eating Habits?
A shift towards healthier eating habits during pregnancy is beneficial, particularly by reducing processed foods and saturated fats. Remember, stay away from significant calorie restriction. Instead, focus on replacing less nutrient-dense foods with options that provide greater benefits for you and your baby.
For more helpful tips for moms and babies, check out our parent hub, where we cover everything from nutrition and wellness to developmental milestones and parenting advice.
This guide is for informational purposes only and should not be used to diagnose health conditions or make changes to medical treatments. Always consult with your healthcare professional for advice.
