It takes just six weeks for the long-term benefits of a diet overhaul to be seen, a University of Auckland study has found.
The study examined whether a change in diet could impact inflammation, which is known to be an early indicator of chronic diseases such as Alzheimer's, Crohn's disease, and type 2 diabetes.
It has long been established that sticking to healthy eating habits can reduce inflammation, but the study set out to examine whether the impact is detectable just six weeks after a change in diet.
Healthy participants who previously had poor eating habits were given either a high or low level of diet intervention.
The results show that changing to a diet high in fish, vegetables, and unrefined cereals has a "remarkable" effect, University of Auckland Professor of Nutrition Lynette Ferguson said.
"We're saying that relatively simple changes, and not even expensive changes, can reduce your risk factors.
"Just look at what a Mediterranean style diet involves. Look at what they're doing that you're not."
The research team examined bio-markers of subjects to assess their level of inflammation. C-reactive protein, a bio-marker which indicates inflammation levels, can be assessed through blood tests.
Participants were found to have a statistically significant reduction in the bio-markers for inflammation when the study concluded.
The six-week time frame was used because the study was intended as a pilot study, Prof Ferguson said.
"Usually these trials go over three months or six months - but over just six weeks we got some quite good effects."
The study also provides hope for other researchers, by demonstrating that relatively short studies can provide robust, statistically significant results.
This has major implications for the costs of future clinical trials, Prof Ferguson said.
Prof Ferguson is now leading a study that examines the effects of diet on people suffering from Inflammatory Bowel Disease. The aim of the research is to tailor diets to those with the disease, based on their genotype characteristics.