Kiwifruit may help combat a female stress response to exercise that's linked to menstrual dysfunction, infertility and osteoporosis later in life.

Scientists have begun investigating whether the vitamin C-rich food might ease exercise-induced stress in women, and were seeking participants for their study.

"Several supplements are known for their beneficial effects on immunity and exercise-induced stress, most notably antioxidants such as vitamin C," said study leader Dr Noha Nasef, of Massey University-based Riddet Institute Centre of Research Excellence.

"However, little attention has been paid to whole foods rich in vitamin C, such as kiwifruit."

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The first links made between food and health had come from observations of communities with specific dietary patterns associated with a reduced risk of disease.

"From these observations, researchers began to focus on isolating and testing the food-derived compounds from the natural food instead of looking at the food as a whole," she said.

This resulted in many studies showing inconclusive and sometimes negative results.

"To better understand the link between food and health we need to study the natural food as a whole."

How locally-grown, antioxidant-rich whole foods might help alleviate stress and immune response to exercise was largely unknown.

What was known, Nasef said, was that exercise could produce stress markers such as cortisol - and specific to gender.

"We also know that women, particularly athletes, suffer long-term consequences of exercise like osteoporosis and menstrual dysfunction, and we think this is linked to the stress response," she said.

"Vitamin C is known to reduce the stress response after exercise and so what we want to determine is whether vitamin C works better when it is eaten as a natural food like kiwifruit."

Her research team was looking for study participants and need 12 healthy active women living in Auckland, aged over 18, with a regular menstrual cycle.

Nasef said taking part in the research was a great opportunity for people to learn about themselves, such as their fitness and they will also be provided with a body composition test for free.

Participants would be asked to come to the research unit five times.

The first visit involved completing questionnaires about their medical history and physical activity, a body composition test and their height, weight and blood pressure would be measured.

Participants will also complete a maximal exercise test, which was the gold standard for measuring cardiovascular endurance.

The other visits involved participants eating a study meal that contained kiwifruit or vitamin C, providing saliva samples and performing a 30-minute exercise on a cycle ergometer.

Women keen to take part can contact the researchers at goldkiwistudy@gmail.com.