A study on food allergies published in the New Zealand Medical Journal says there is a lack of hospital services for those suffering from the disorders.

The report says there is currently no information available about those who have food allergies, and the lack of data means hospital services for children and adults are very limited.

One of the authors of the report, Dr Rohan Ameratunga, says access to medical services outside Auckland for those with severe reactions is a real problem.

He says those who can afford it travel long distances for treatment, but many others are probably struggling on their own.

Dr Ameratunga, who is an allergy specialist at Auckland Hospital, says between 6% and 8% of children, and from 2% to 4% of adults have some sort of significant food allergy.

The effects of such allergies can range from mild discomfort to anaphylactic shock - which can be fatal.

Dr Ameratunga says another issue is that adrenaline auto-injectors - used to treat acute anaphylaxis - are not publicly funded, making it difficult for lower income families to get them.

He says further studies into the disorder are planned for later in the year.