Brazil Nuts & Fertility: Fact or Fiction?

If you dream of starting a family soon, you’re probably looking for a diet that increases your chances of getting pregnant. There are many foods that can help with implantation. In fact, fertility food fads are a dime a dozen these days, and it can be grueling to determine which foods actually prepare your body for conception. 

Case in point: Brazil nuts, a nutrient-dense professed superfood lauded for its fertility-boosting properties. Is there empirical data to back up claims about Brazil nuts’ benefits for fertility?

On their own, there’s no evidence to suggest that eating Brazil nuts enhances your ability to conceive—but they can play a supporting role in a holistic pregnancy-supporting diet.

In this article, we’ll separate the science of Brazil nuts from the pop science to help you build a diet plan that supports your pregnancy journey every step of the way.

Brazil Nuts Nutrition 101 

Native to the Amazon forest in South America, Brazil nuts are a micronutrient powerhouse. Brazil nuts are rich in:

• Copper
• Magnesium
• Phosphorus
• Manganese
• Zinc
• Thiamine
• Vitamin E

To top it all off, Brazil nuts are one of the most selenium-dense foods in the world. This is mineral at the root of this nut’s fertility-enhancing properties.

Brazil Nuts Fertility Benefits 

Selenium is intimately involved in several reproductive dynamics in the body. Numerous studies have highlighted the following roles it may play in fertility:

• In one study, women with unexplained infertility had lower levels of selenium in the fluid surrounding their eggs.
• Another study showed that supplementing with selenium for 8 weeks reduced inflammation and symptom severity in women with polycystic ovary syndrome (PCOS)—a hormonal imbalance that’s responsible for many cases of female infertility. In fact, supplementing with selenium even positively influenced reproductive outcomes for women with PCOS.
• Maintaining proper levels of selenium may support both maternal health and fetal development, promoting immune system development and helping newborns reach a healthy birth weight.
• Selenium may also play a major part in male fertility, stimulating testosterone production and improving sperm quality as well as sperm count. 

Pre-conception: fertility foods  

While research into the specific reproductive actions of selenium is ongoing, it’s clear that this essential trace nutrient will foster a supportive environment for the growth of your baby.

How much selenium should I eat? 

The recommended amount of selenium intake for men and women is the same: 55 micrograms per day. When pregnant, women are advised to increase their dosage to 60 micrograms per day.

A single Brazil nut contains an average of 96 micrograms of selenium, well over the recommended daily intake (RDI) for both men and women. Though no other food compares to the punch Brazil nuts pack, you can find selenium in:

• Fish, like halibut, Yellowfin tuna, and sardines
• Meat, like turkey, ham, and beef steak
• Dairy, like cottage cheese and eggs

Does selenium help during pregnancy? 

Complementing your diet with selenium may be advantageous when you’re pregnant as well beforehand.

During gestation, selenium supplementation has been shown to:

• Increase levels of estradiol, progesterone, and T4—three hormones that play a crucial role in maintaining a healthy pregnancy.
• Support the body in processing vital nutrients obtained from the rest of your diet.
• Promote antioxidant activity to keep the body’s cells healthy.

Antioxidants play an essential role in the body by fighting against oxidative stress—a state of instability in the body’s cells. In pregnant women, oxidative stress may contribute to poorer pregnancy outcomes.

While the specific role selenium plays during pregnancy is still under investigation, research suggests that preventing low selenium levels can help you to avoid pregnancy complications and miscarriage.

Can You Eat Too Many Brazil Nuts? 

Are there any downsides to downing Brazil nuts for a fertility boost? Given Brazil nuts’ astronomical selenium content, it is possible to go overboard and develop selenium toxicity. 

One tell-tale sign of selenium poisoning is a pungent, metallic, or garlicky taste in the mouth. Selenium toxicity can result in:

• Fragile hair and nails (or loss of both)
• Teeth discoloration
• Rashes
• Gastrointestinal issues, like nausea, diarrhea, and bowel discomfort
• Nervous system issues

If persistent, selenium poisoning can also have severe consequences, like breathing difficulty, kidney failure, and even heart attack. Teenagers and adults are not advised to consume more than 400 micrograms of selenium per day—so trim your nut count to no more than a few per day.

How To Eat For Fertility

As it turns out, what nutrients you consume or supplement with may be just as important as when you consume them in your pregnancy journey.

The majority of selenium and fertility-related studies demonstrate the most positive results during follicular development and fetal gestation—the earlier stages of pregnancy, when your baby is just beginning to grow.

Let’s take a closer look at how to build your fertility and pregnancy-supporting diet at every stage of your future baby’s development.

Pre-conception: fertility foods for fertility 

Two B vitamins, Folate (vitamin B9) and vitamin B12, are associated with A-grade results when it comes to increasing your likelihood of getting pregnant. Here’s what to know about these two nutrients if you’re trying to conceive:

• Folate – Folate is a star nutrient when it comes to improving fertility outcomes, and has been linked to improved fertilization rates. To reap the pregnancy-boosting benefits of folate, you can crunch on cruciferous veggies like broccoli and brussels sprouts (or your morning avocado toast). You can also take a folic acid supplement to reap some benefits.
• Vitamin B12 – The second “B” vitamin to focus on is vitamin B12. In one study, women who maintained recommended levels of B12 were 2.04x more likely to successfully carry a pregnancy to term than women with a B12 deficiency. So, taking a daily B12 supplement or boosting your breakfast with salmon, fortified cereal, or eggs may increase your odds of conceiving.

As for guys? While antioxidant-rich foods don’t appear to influence female fertility, using them to supplement men’s diets may enhance fertility in males. This means that individuals eager to start Dad-life should load up on blueberries, kidney beans, and dark leafy greens.

Nutrients for your first trimester 

In your first trimester—up to your 12th week of pregnancy—keep your B vitamin levels boosted. In addition, it’s beneficial to integrate the following foods into your fertility diet:

• Calcium – Calcium is essential for developing a strong skeletal system. It also fosters tenacious muscular, circulatory, and nervous systems in your baby. You can get calcium from dairy products like cheese and yogurt, as well as a refreshing cup of OJ. Be sure to eat vitamin D-rich foods (like salmon, tuna fish, and eggs) at the same time to aid calcium absorption and ensure your growing baby reaps the bone-strengthening benefits.
• Omega-3 fatty acids – Omega-3s, which are mostly found in fish, are critical for healthy brain and eye development in growing fetuses. They also may help offset the low moods that many women can experience during pregnancy. To improve your levels, it’s recommended you enjoy at least 2 servings of low-mercury seafood per week (6 oz. each) or take a fish oil supplement alongside your prenatal multivitamin.

Those first few weeks with your embryo are all about balance, aiming for the recommended ratios of key macronutrients at every meal. Ideally, your plate would reflect around 50% carbohydrates (load up on the veggies!), 25-35% good-for-you fats, and 20-25% protein.

Nutrients for your second and third trimester 

Rather than adding more nutrients, this stage of your pregnancy is all about knowing what foods to avoid to help your baby to a healthy birth. 

Here’s what to nix from your fridge and pantry:

• Seafood – While consuming fatty fish can work to you and your baby’s benefit early on, it’s not ideal when you’re further along in your pregnancy. Many types of fish are known to carry substantial amounts of mercury, so aim to limit your seafood intake to low-mercury sources like shrimp, canned light tuna, and sardines.
• Unpasteurized foods – Wondering if you can have blue cheese while pregnant? Well, pasteurization is the process of making certain foods, particularly dairy, suitable for consumption by treating them with heat. Unpasteurized foods, like blue cheese, are more likely to contain bacteria, which may cause infections that can be damaging to a developing baby. If you’re a dairy fan, save unpasteurized cheeses like feta, blue cheese, and brie for after you’ve given birth.

And as for those selenium-rich Brazil nuts? You’re free to keep munching on 1 or 2 a day to set you and your baby up for a happy birth (and beyond).

Optimize Your Future Baby’s Nutrition with SneakPeek 

Food plays an enormously important role in preparing your body for a baby, keeping your prenatal health on solid footing as you begin the path towards motherhood. It’s also important to understand which foods to avoid when trying to get pregnant, which we’ve written about in detail on our blog! 

Now that you’ve cracked the nut on if Brazil nuts can boost your fertility—don’t let the spirit of investigation fall to the wayside! Kick off your pregnancy informed and empowered with the SneakPeek At-Home Early Gender Blood Test. 

Using your baby’s DNA found in an easy-to-collect sample of your blood, SneakPeek can determine the sex of your baby as early as 6 weeks into your pregnancy. In fact, with over 99% clinically-proven accuracy¹, it’s the #1 OBGYN-recommended at-home gender test on the market. Plus, both your data and results are privacy-protected, giving you answers and peace of mind. 

Join the 1 million moms who’ve harnessed the power of science to learn more about their little ones by choosing SneakPeek Test.

Sources:

1. Food Research International. Brazil nuts: Nutritional composition, health benefits and safety aspects. https://www.sciencedirect.com/science/article/abs/pii/S096399691730474X?via%3Dihub
2. National Institute of Health. Selenium dependent glutathione peroxidase activity in human follicular fluid. https://pubmed.ncbi.nlm.nih.gov/7554284/
3. National Institute of Health. Selenium Supplementation and the Effects on Reproductive Outcomes, Biomarkers of Inflammation, and Oxidative Stress in Women with Polycystic Ovary Syndrome. https://pubmed.ncbi.nlm.nih.gov/26267328/
4. National Institute of Health. The role of selenium in human conception and pregnancy. https://pubmed.ncbi.nlm.nih.gov/25175508/
5. National Institute of Health. Maternal Selenium, Copper and Zinc Concentrations in Early Pregnancy, and the Association with Fertility. https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC6683068/
6. National Institute of Health. Selenium, Selenoproteins, and Female Reproduction: A Review. https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC6321086/
7. Healthline. 7 Proven Health Benefits of Brazil Nuts. https://www.healthline.com/nutrition/brazil-nuts-benefits#:~:text=Brazil%20nuts%20are%20rich%20in,%2C%20on%20average%20(3).
8. National Institute of Health. Selenium. https://ods.od.nih.gov/factsheets/Selenium-HealthProfessional/#h4
9. National Institute of Health. Dietary Folate and Reproductive Success Among Women Undergoing Assisted Reproduction. https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC4172634/
10. National Institute of Health. Diet and Fertility: A Review. https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC5826784/
11. National Institute of Health. Omega-3 Fatty Acids and Pregnancy. https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC3046737/
12. University of California San Francisco. Eating Right Before and During Pregnancy. https://www.ucsfhealth.org/education/eating-right-before-and-during-pregnancy
13. Healthline. Eating Well in Your Second Trimester. https://www.healthline.com/health/pregnancy/second-trimester-diet-nutrition#tips-for-healthy-eating