Eating barbecued, high sugar and processed foods could harm a woman’s chances of becoming pregnant – new Australian study shows

18 April 2018

Infertility is a growing global phenomenon, thought to affect about one in six people in developed countries. It is well known that obesity can lead to ovulation difficulties, and impede the chances of falling pregnant. Now researchers at Melbourne’s Hudson Institute of Medical Research have found that having a diet high in sugary, processed and charred, blackened foods may also have a greater impact on fertility and pregnancy than previously thought.

The study, Obesity associated advanced glycation end products within the human uterine cavity adversely impact endometrial function and embryo implantation competence, was published this month in the journal, Human Reproduction. (available on CKN under embargo)

The team examined the uterus cavity of 17 lean and fertile women, and 16 obese women struggling to conceive, and found that the obese group had “very significantly elevated” levels of a sugar by-product called advanced glycation end products (AGEs).

Certain proteins can become ‘toxic’ and produce AGEs after exposure to sugar or through consuming sugary, processed and blackened foods, such as barbecued or char-grilled meals. AGEs can also form naturally in the body. Their presence was found to trigger inflammation in the endometrium in infertile women with obesity. This may even further reduce the likelihood of a woman falling pregnant and could even contribute to pregnancy complications.

Hudson Institute research scientist Dr Jemma Evans, who led the study, said these sugar by-products made it harder for an embryo to implant.

“We also found that AGEs interfere with placental development, which may contribute to pregnancy complications. This is the first time anyone has demonstrated in laboratory studies that specific toxic factors in the womb can compromise fertility,” Dr Evans said.

The findings could have significant implications for fertility treatments and the dietary advice offered to women planning to get pregnant. People with high AGE levels may be told to forgo IVF and try changing their diet first. There are also drugs that could be used to force AGE levels down in older women who do not have time to implement lifestyle changes.

The study’s co-author Professor Lois Salamonsen said women hoping to have a baby could be told to avoid sugars and highly-processed and highly blacked food.

“If you really grill or barbecue food, the browner it gets the more AGEs there are there,” Professor Salamonsen said. “One could advise that you don’t eat really heavily barbecued food, or heavily fried, or heavily grilled, but cook things more gently.”

A low-AGE diet has been shown to improve health outcomes in other diseases, such as reducing insulin resistance in diabetes, in as little as four weeks. To date, this controlled diet hasn’t been tested in relation to fertility. Dr Evans says the uterus is likely to respond to a short-term intervention, like a dietary change, to restore fertility because it regenerates every month.

“Unlike the heart, kidneys or liver, the endometrium is the only place in the body that completely regrows every 28 days. If successful, this simple dietary intervention may become a more holistic way to improve fertility and potentially avoid the need for costly interventions such as IVF.” Dr Evans said.

The research may also have implications for women with polycystic ovary syndrome, after another study found women with the condition (which can also cause infertility) had higher rates of AGEs in their blood.

What are advanced glycation end products (AGEs)?

  • Advanced glycation end products (AGEs) are compounds which are formed when proteins, lipids or nucleic acids change during exposure to sugar.
  • AGEs are known contributors to oxidative stress and inflammation and have been linked to the recent epidemics of diabetes and cardiovascular disease.
  • The pool of AGEs found in the human body can either be formed naturally within the body, or accumulate through dietary exposure to certain foods or beverages.
  • AGEs are formed in foods by heat-processing such as frying, grilling, caramelising or roasting (examples include browned meat or toast). Highly processed foods have a high content of AGEs.
  • Preclinical studies suggest that otherwise healthy proteins in the body can react with sugars (such as those consumed in foods or beverages) to form AGEs within the body.