Diet currently accounts for nearly a tenth of the global burden of disease and is linked to reproductive outcomes in men and women. A recent literature review found that a higher adherence to the Mediterranean diet, a ‘profertility’ diet, or a Dutch ‘preconception’ diet was associated with better pregnancy or live birth  outcomes after IVF treatment. While showing positive associations, further research is necessary to confirm these results.

Fertility diets

The Mediterranean diet is generally comprised of high intake of whole grains, vegetables, fruits, nuts, legumes and/or pulses, and olive oil; moderate intake of non-fat or low-fat dairy products, seafood, and wine; and low consumption of poultry and red meat.

The ‘profertility’ diet is based on findings from the EARTH study and comprises higher intake of supplemental folic acid, vitamin B12, vitamin D, low-pesticide fruits and vegetables, whole grains, seafood, dairy, and soy foods; and lower intake of high pesticide fruits and vegetables.

The Dutch ‘preconception’ diet is comprised of: high daily intake of whole grains, vegetables, and fruit; weekly intake of at least three servings of meat or meat replacers and one serving of fish; and use of monounsaturated or polyunsaturated oils.

In comparison, the Western dietary pattern is characterised by a high intake of red and processed meats, high-fat foods, refined grains, and high-sugar drinks and desserts, and is relatively low in fruits, vegetables, whole-grain foods, poultry, and fish. This diet has been shown in animal studies to be detrimental to fertility.

Do pesticide residues make a difference?

Pesticides are commonly applied to fruit and vegetable crops (FVs) worldwide. Conventionally-grown FVs are a major source of pesticide exposure in the general population with common detection in the urine and bloodstream. It is also known that switching from eating conventionally grown produce to eating organic produce can substantially decrease the quantity of pesticides in human samples in a short period of time (even one week).

We know that being exposed to pesticides at work or living in close proximity to agricultural areas that frequently use pesticides, is related to adverse reproductive outcomes. However, is dietary pesticide exposure (within the range of typical human exposure) associated with adverse reproductive consequences?

For men

Recent studies have demonstrated that consumption of FVs with high levels of pesticide residues have been associated with a lower total sperm count and a lower percentage of morphologically normal sperm among men presenting to a fertility clinic. In the Rochester Young Men’s Study, a population of healthy men aged 18–22 years, low-pesticide residue FVs was associated with improved semen quality, whereas the total intake of fruit and vegetables was unrelated to semen quality. Another study of sub-fertile men, showed that low pesticide residue FVs may have a positive impact on fertilisation while high pesticide residue FVs negatively affect semen quality.

For women

Animal studies have shown that early exposure to very low doses of pesticides during pregnancy can lead to cell death in embryos, but whether the same is true for humans was not known. Now, new research suggests that the ingestion of pesticide-treated FVs is associated with a reduced chance of pregnancy and an increased chance of pregnancy loss in humans. Women who ate FVs with the highest pesticide amounts were 18 percent less likely to get pregnant each IVF cycle, up to 34% more likely to miscarry and 26% less likely to have a live birth.

Which fruits and vegetables have the highest levels of pesticides?

Use the Environmental Working Groups (EWGs) Shopper’s Guide to Pesticides in produce. This handy guide helps you avoid the Dirty Dozen, the non-organic fruits and vegetables that are highest in pesticide residues and choose non-organic items from the Clean Fifteen list.

Practical tips

  • Consider buying organic fruits and vegetables, especially those known to have high pesticide residues, the “dirty dozen”
  • Consume lots of fruits and vegetables from the “clean fifteen” list
  • Wash all fruits and vegetables really well. Use a warm salt-water solution and let everything soak for 10-15 minutes. Otherwise use a product like Abode’s Fruit & Veggie Wash that will remove the residue in 30 seconds.
  • Continue to eat a variety of fruits & vegetables

For more information & support with your dietary requirements for fertility, book with one of our naturopaths. Make an appointment via our website www.nbhealthandfertility.com.au.