WCFS - Wageningen Centre for Food Sciences | WCFS Food Summit 2001: Biomarkers: How strong is the scientific evidence?

OFFICE ADDRESS
Diedenweg 20
6703 GW Wageningen
The Netherlands

POSTAL ADDRESS
P.O. Box 557
6700 AN Wageningen
The Netherlands

T +31 317 485 383
F +31 317 485 384
e-mail info@wcfs.nl
website www.wcfs.nl

Food Summit

2005: Making sense of food

2004: Diet and the metabolic syndrome

2003: Mining food microbes

2002: Texture Dynamics

2001: Biomarkers: How strong is the scientific evidence?

2000: Impact of genomics on food sciences

1999: Food Texture: Perception and Measurement

news archive

publication archive

vacancies

WCFS Food Summit 2001: Biomarkers: How strong is the scientific evidence?

The topic for this year's annual WCFS Food Summit was biomarkers and how effective are biomarkers for assessing effects of diet on cardiovascular health. The meeting, which was held in Wageningen from 28 to 30 November 2001, was attended by 75 specialists in the field from Europe and the USA.

The keynote lectures, workshops and plenary discussions addressed the controversial issue of the validity of biomarkers. Can health claims about foods be substantiated by effects observed on biomarkers of risk factors for cardiovascular disease? Specifically, the debate focused on the effects of diet on biomarkers such as blood lipids, homocysteine, antioxidant status, arterial wall biomarkers, blood pressure, arrhythmia and haemostatic factors.

Biomarkers

A biomarker is an indicator of disease risk. Formal proof for efficacy of dietary supplements or functional foods requires clinical trials with hard endpoints, such as morbidity or death. However, it is often not feasible to measure hard endpoints. Therefore, a biomarker can be used as a Œpredictor¹ of the actual effect of diet on disease in the following way:

Biomarkers for cardiovascular disease can be classified as follows:
- risk factors, such as serum cholesterol and plasma homocysteine;
- manifestations of altered function, such as intima-media thickness of carotid artery wall.

For research purposes, a biomarker should be easily measurable and potentially modifiable within the timeframe of a study. Furthermore, a biomarker is only valid when a change in the biomarker can accurately predict a change in disease risk. The latter is essential when biomarkers are used to support health claims.

Outcome

A variety of biomarkers of risk were discussed at the meeting. These included blood levels of cholesterol and of homocysteine, blood pressure, markers of oxidative processes in the body, and markers of arterial wall anatomy and function.

A prerequisite for a biomarker is its validity; a change in the value of the biomarker should reliably predict a change in disease risk. The validity is different for different biomarkers, with validity of blood cholesterol levels and blood pressure being the most established.

The central question during this meeting was whether health claims on foods can be justified by proven effects of dietary ingredients on risk biomarkers. This led to stimulating debates. Even well validated biomarkers should not be relied on alone. For instance, relying on short-term biomarkers alone may mask long-term adverse effects that can only be detected in longterm clinical trials on hard endpoints.

There was consensus that biomarkers of risk are valuable tools for evaluating the health effects of foods. Biomarkers may help to sustain health claims, particularly if long-term controlled trials on hard endpoints are not feasible.

For more information on the Food Summit contact WCFS.