Fat challenge test may identify dietary health effects

A high-fat challenge test employing cutting edge – metabolomic technology may generate more and better information about the health effects of dietary ingredients and supplements, say researchers.

Researchers from TNO have demonstrated that the method, which is assessed using metabolomics and proteomics technology, can provide additional information on the metabolic effects of dietary ingredients and thus help to provide greater information on the health effects of diet than current testing methods.

The researchers, led by Dr Ben van Ommen, principal scientist and program director of systems biology at TNO, said that the extra information provided by the new testing methods could be of use in the substantiation of health claims.

“Diet only has minor effects on health outcomes. The changes are mostly subtle, but they can be very important to health,” said van Ommen.

“Nowadays health is more seen as the ability of a person to adapt to changes (stressors). The body deals with stressors on a daily basis, especially in terms of metabolism and inflammation. By measuring the response to a stressor, we can get an indication of a person's health,” he added.

Dr van Ommen said that the main challenge for food and nutrition scientists currently is demonstrating that dietary interventions actually produce a change in health status.

“This is not easy, we know that from the way that EFSA has rejected many health claims dossiers for this reason in the past,” said van Ommen.

Changing thinking

Dr van Ommen and his team at TNO asked themselves whether there would be a better way to quantify these many subtle changes that a dietary intervention may have.

“We’ve come to a concept we call perturbation of homeostasis,” he affirmed.

Homeostasis is the regulation of the bodies internal processes in a healthy and balanced status. Dr van Ommen said that by challenging or perturbing this system, the test can give a good idea of a person’s health.

The nutrigenomics expert explained the concept by noting that it is generally more difficult to judge a persons health if they are in a resting state. He said that when people are in stressful or challenging situations then it becomes easier to assess health, by judging how well they cope with such challenges.

“If you were to run a marathon then I could very easily tell you about your physical state. But if you are just sitting in a chair then it would be more difficult,” said Dr van Ommen.

“The same principle is true of many other aspects of physiology,” he said.

Challenge tests, such as the much used oral glucose challenge, can therefore help researchers to learn more about metabolic physiology, and the effects of diet on these processes, by challenging the metabolism.

“These methods report your metabolic state much more accurately,” he said.

“We have exploited this fact to better understand a dietary intervention. But instead of using glucose, we are using a standardized high fat meal,” he explained.

The test

Using metabolomic and proteomic testing methods, the TNO research team can track the changes in over 200 metabolites and 100 proteins when a challenge test is administered. This amount of data is said to give a much clearer understanding of how our diet affects health.

In the current research the team tested the principle by using a high-fat challenge test to compare metabolic data from before and after a dietary intervention.

The researchers found that administering the high fat challenge test after a five week change in diet brought about much clearer indications of metabolic changes than using existing testing methods, such as testing for metabolites in a fasting state.

“The fasting state did provide the information on metabolic changes, we had to look very carefully to find it, but it was there. So yes, the old fashioned way works a little, but the perturbed metabolites from the challenge test reported the differences much more than the older methods,” said Dr van Ommen.

He explained that the challenge test provide much more information and evidence of an effect than the traditional fasting test method.

“We need to prove that diet is healthy. We don’t want to prove that it prevents a disease, but more that it maintains or improves health … The key point of this test is to kick the system, to test how well it copes. That is the best way to test for health rather than a disease,” he added.

Source: TNO