Eating for Fertility: How to Improve Your Egg Quality After 40

Eating for Fertility: How to Improve Your Egg Quality When over 40: 

It's true ladies! Our fertility starts to tank as we age, especially as we near the age of 35 and older! But it doesn’t mean we can’t beat the odds through a healthy lifestyle. There are several things you can do today that can help you preserve your eggs and your overall fertility for as long as possible EVEN if you are over 40!

So here are 5 tips to keep in mind:

1. Minimize Oxidative Stress:  

Oxidative stress is one of the primary ways you can wreak havoc on your egg quality.

You have probably seen oxidization take place outside of the body before. For example, when you slice an apple and expose it to oxygen you notice that it begins to age quickly. This is due to oxygen coming in contact with the apple and causing it to brown via a chemical reaction called oxidation.

These types of chemical reactions happen in the body every day except they are ALOT more complex.

Just like an apple naturally browns when it touches the air, our cells naturally release oxidative compounds as a result of everyday cellular function. However, you can expose your body to specific conditions largely through your lifestyle that encourage excess oxidation.

Excess oxidative stress leads to systemic inflammation and accelerated "aging" of cells including those that make up our reproductive organs. This is why it is no surprise that emerging research is supporting that oxidative stress may damage your egg cells and ovaries (1).

Lifestyle Factors that Have Been Shown to Increase Oxidative Stress:

-Excessive physical and emotional stress

-A lack of physical activity

-High consumption of processed foods,

-Exposure to endocrine-disrupting compounds like pesticides and heavy metals

This is why it is important to act preventatively to reduce the oxidative load your body has to handle.

However, there are several things we can do to combat oxidative byproducts in the body such as consuming plenty of ANTI-oxidants through eating a diet rich in fruits, vegetables, and whole grains, and improving our macro and micro-nutrient intake.

This leads me to my next few tips:

2. Take a Mineral Rich Multivitamin:

God has equipped our body with the ability to make its own ANTI-oxidants to combat the natural oxidation that takes place.

Some of these antioxidants include glutathione and superoxide dismutase. These antioxidants are largely dependent on minerals to function and operate, especially minerals such as zinc, selenium, copper, iron, and manganese (2).

Minerals are also vital for regulating the hormones that are critical to ovulation. However, it can be challenging to obtain many of these nutrients through diet alone. This is where a well-designed prenatal or multivitamin supplement can help ensure adequate intake of key nutrients for fertility.

Also, prenatal vitamins typically provide adequate amounts of Iron, B12, and folate which are 3 nutrients associated with increased live birth rates. 

I typically recommend my clients take a vitamin that has at least 50% or more of their daily value of zinc, selenium, copper, manganese vitamin C, Vitamin E, and 100% of their daily value of B12 and iron to ensure they are supporting their antioxidant pathways and optimal fertility all around.

It's also important to note that the CDC recommends that you have an intake of at least 400mcg of folate starting at least 3 months prior to trying to conceive due to its vital role in DNA replication and it's role in preventing neural tube defects during pregnancy.

Take Coenzyme Q10 :

Coenzyme Q10, also known as CoQ10,  is an antioxidant that helps protect our tissue from oxidative stress and inflammation but it, unfortunately, declines as we age.

Some studies have shown that decreased levels of CoQ10 reduce oocyte (egg) quality and encourage age-related declines in fertility. However, supplementation with Coq10 has been shown to slow down cellular aging. It has also been shown to increase conception rates in multiple randomized controlled research trials, even in women with impaired ovulation (1).

This is why supplementation with this antioxidant is often recommended by medical practitioners for women who are nearing the age of 35 and wish to conceive. 

Most medical practitioners recommend between 100-600mg of CoQ10 daily however it is important to talk to your doctor or dietitian about which dose is best for you. I personally base CoQ10 supplementation on my patient's medical history, lifestyle factors, my understanding of their oxidative load, and my assessment of my patient’s dietary antioxidant intake.

4. Avoid a High Fat Diet:

Thanks to today’s diet culture, there seems to be a myth going around that you can eat as much fat as you desire without health consequences, but this is very far from the truth, especially when it comes to fertility!

We definitely want to ensure adequate fat intake when trying to conceive but excess fat intake beyond your body's needs can result in a dangerous environment for your eggs and hormones, even if the fat you eat comes from “healthy" sources.

Excess fat intake can encourage suboptimal egg quality and overall fertility in two ways: 

Promotes Excess Adipose Tissue: 

Even if you are on a keto diet or a low-carb diet, your body will store the excess fat it doesn’t need directly as body fat. This is why a high-fat diet causes excess fat mass in many people, especially those who are genetically susceptible. 

Eventually, excess fat gain results in poor oxygenation of tissues, accelerated tissue cell death, and the subsequent release of inflammatory compounds. These compounds and the damaging effect they have on the body are collectively referred to as oxidative stress which we will talk about later.

This oxidative stress can damage your eggs by interfering with the DNA process needed for eggs to mature. These inflammatory compounds also interfere with the ability of hormones like insulin to communicate with the cells which eventually causes insulin resistance. Insulin resistance can create an imbalance in hormones like testosterone and estrogen and block ovulation (1,3,4).

So not only can excess fat reduce your egg quality, but it can also prevent your body from releasing an egg properly every month.

Interferes with organ-to-organ hormone signaling:

Excess dietary fat regardless of increases in body fat can still affect fertility by interfering with what we call the Hypothalamic pituitary axis (HPO axis) which describes the complex synergy of hormones that are essential for ovulation. (3).

This may be in part why some studies have associated excess fat intake with the early onset of menopause though more studies are needed (5).

How much fat should you eat when trying to conceive?

Women should consume no more than 35-30% of their calories from fat when trying to conceive can range from about 65-80 grams of fat daily for most women. As a side note, most of the women who see me for infertility or impaired ovulation are eating about 30 or more grams over their needs for dietary fat, and see a return to normal ovulatory patterns once they improve their fat intake and composition.

5. Prevent Spikes in Blood Sugar:

Last but not least, one of the most crucial factors in maintaining healthy eggs and slowing down age-related fertility decline is maintaining proper blood glucose levels even if you do not have diabetes!

High blood glucose levels can disrupt hormone signaling and reproductive processes such as ovulation (6,7).

However, many women do not pay attention to their blood sugar until they are facing a scary diagnosis like prediabetes or diabetes, which is a BIG mistake, especially if you are over the age of 35.

Having spikes in blood glucose constantly throughout the day requires your body to secrete more insulin. Insulin is our storage hormone, so the longer it is on the scene, the more fat your body stores, which, as we discussed earlier, can play a role in the hormone imbalances, oxidative stress, and impaired ovulation that we see follow insulin resistance (3,6,7).

To prevent this, it is essential to adopt an active lifestyle and a balanced diet that minimizes blood glucose spikes and improves insulin response. 

Here are 3 easy tips I give all my patients to promote blood sugar balance:

  1. Eliminate simple sugars: opt for whole, high-fiber sources of sugar such as whole grains and fruit.
  2. Walk after eating: You can lower your blood glucose after meals by 1-3 points for every 1 minute you walk. This means that Even just a 15-minute walk after meals can significantly reduce blood glucose and curb insulin spikes.
  3. Do not eat more than 3-4x per day: There are exceptions to this, but most women do not need to eat more than 3 evenly spaced meals per day.  This gives the body adequate time to clear out excess blood glucose levels and lower insulin which promotes blood sugar balance and weight maintenance. 

Besides preventing blood glucose spikes, it is also essential that you keep an eye on your blood glucose levels by checking them regularly. A great way to do this is by asking your doctor to check your HbA1c, this is a blood test that indicates what your average blood glucose levels have been over a 3-month period.

If your HbA1c is 5.7 or higher, then you may have prediabetes or diabetes and you may need to work with a healthcare professional before trying to conceive. 

How long does it take to improve your egg quality?

If you read this far, you might be asking yourself " Just how long would it take me to improve my egg quality by improving my lifestyle?

The short answer is that it can take about 3 months to see improvements in your egg quality.

This is because each month your body chooses a batch of egg cells to mature and enter your menstruation cycle.

Out of this batch, only 1 egg will be released for ovulation. However, prior to ovulation, it takes 85-90 days or approximately 3 months for each of these eggs to mature. This means that the lifestyle choices you make during that period can greatly affect the overall odds that the egg your body chooses during ovulation will be healthy and well-developed.

It also means that you need at least 3 full months for an entirely new batch of egg cells to enter your menstrual cycle.

This is why I often recommend consistent dietary and lifestyle changes for at least "2 egg cycles" or 6 months prior to conception so we can make sure you have the healthiest egg possible when trying to conceive.


So what should you do if you are over 40 and want to have the best egg quality possible? The simple answer is to change your lifestyle now before it is too late! Adopting an active lifestyle and a balanced diet, especially a diet that is rich in antioxidants, low in simple sugars, and not too high in fat, may be vital to prolonging your fertility. 

Do you need 1 on 1 support?

Working on all the areas that affect fertility can sometimes feel overwhelming, but that is because it isn't realistic to work on each of these areas all at once! That is where I offer support. As a fertility dietitian, I help you implement lifestyle changes that support fertility through realistic and achievable goals, while also monitoring various fertility and metabolic markers to ensure you are moving in the right direction.

If you are 35 or older and wish to do everything in your power to prolong your fertility, I invite you to book a free Fertility discovery call with me so we can discuss what a fertility-promoting lifestyle would look like for you.


1. Florou P, Anagnostis P, Theocharis P, Chourdakis M, Goulis DG. Does coenzyme Q10 supplementation improve fertility outcomes in women undergoing assisted reproductive technology procedures? A systematic review and meta-analysis of randomized controlled trials. J Assist Reprod Genet. 2020 Oct;37(10):2377-2387. doi: 10.1007/s10815-020-01906-3. Epub 2020 Aug 7. PMID: 32767206; PMCID: PMC7550497.

2.Wołonciej M, Milewska E, Roszkowska-Jakimiec W. Trace elements as an activator of antioxidant enzymes. Postepy Hig Med Dosw (Online). 2016 Dec 31;70(0):1483-1498. doi: 10.5604/17322693.1229074. PMID: 28100855.

3.Hohos NM, Skaznik-Wikiel ME. High-Fat Diet and Female Fertility. Endocrinology. 2017 Aug 1;158(8):2407-2419. doi: 10.1210/en.2017-00371. PMID: 28586412; PMCID: PMC6283234.

4. Snider AP, Wood JR. Obesity induces ovarian inflammation and reduces oocyte quality. Reproduction. 2019 Sep;158(3):R79-R90. doi: 10.1530/REP-18-0583. PMID: 30999278.

5..Biela U. Czynniki determinujace wiek naturalnej menopauzy [Determinants of the age at natural menopause]. Przegl Lek. 2002;59(3):165-9. Polish. PMID: 12184031.

6. Chavarro JE, Rich-Edwards JW, Rosner BA, Willett WC. A prospective study of dietary carbohydrate quantity and quality in relation to risk of ovulatory infertility. Eur J Clin Nutr. 2009 Jan;63(1):78-86. doi: 10.1038/sj.ejcn.1602904. Epub 2007 Sep 19. PMID: 17882137; PMCID: PMC3066074.

7.Liao, X., Xie, X., Wang, X., Luo, X., Wang, Y., & Yang, X. (2018). The impact of blood glucose fluctuations on ovarian reserve in patients with type 2 diabetes mellitus. Gynecological endocrinology, 34(3), 205-209. doi:

Written by
Ciara Dove-Reid, RDN
Registered Dietitian Nutritionist

Ready to Eat Wisely the way God intended?

Give us a call for a free 15-minute discovery consultation or view our programs.