Plant Foods and Human Health

We are what we eat, according to the old adage, but how much do we really know about the composition of the foods in our diet? The bioactive compounds present in our food have a major influence on our health, but with very few exceptions, we know only a little about the molecular complexity of these foods.

The quality of food is essentially due to the broad spectrum of molecules that determine its biochemical composition, nutritional value, taste, fragrance and appearance. This molecular complexity includes not only the biological raw material of the food, but also any food additives, changes induced from food processing, as well as from the time and conditions of storage and delivery. The biochemical profile of a food is also a key factor in determining important properties such as shelf life, nutritional stability and market value.

Metabolomics is a specialized form of analytical biochemistry in which researchers are able to dissect the composition – metabolome – of biological samples such as foods. Through metabolomics, it is possible to separate, identify and quantify the components of complex organic extracts in food such as amino acids, sugars, volatile flavors, alkaloids, polyphenols, carotenoids and anthocyanins.

“Metabolomics enables us to determine the biological and metabolic fingerprint of food,” according to Annalisa Tassoni of the Department of Experimental Evolutionary Biology at the University of Bologna in Italy. “This helps us determine the impact of these forces on an individual metabolism”.

Metabolomics is gaining considerable attention in the medical world where it is becoming an important tool to correlate the biochemical composition of food with physiological effects.

“We can then develop strategies for disease prevention and intervention,” Tassoni says.

Foods that have a medicinal effect on human health contain what are called nutraceutical compounds – biological molecules or extracts that have beneficial properties for human health.

In most diets, plant products provide the main part of human food intake. Diets rich in fresh fruits and vegetables are generally associated with a reduced risk of developing cardiovascular disease, obesity, Type 2 diabetes and many types of cancer.

Antioxidant compounds, for example, are found in fruits, vegetables and their derivatives such as juices. The compound resveratrol, found in several types of grapes and wine, has received particular attention as a possible explanation for the so-called “French paradox”, the apparent ability of moderate red wine consumption to reduce the risk of cardiovascular disease. This compound also may act as a chemopreventive agent against several types of cancer.

Anti-nutraceutical compounds – those with negative effects on human health – can also be found in many foods. The human diet contains significant amounts of compounds such as biogenic amines that are either present naturally or as a result of food processing, contamination by microorganisms, storage or spoilage. At low concentrations, some of these compounds are essential for optimal cell growth and development, but, if present at high concentrations, they may have detrimental effects and a clear toxicological action with allergenic, mutagenic and carcinogenic effects.

“These compounds need to be quantified, profiled and monitored,” says Tassoni. “Our research is now focused on the interaction between formation of anti-nutraceutical compounds and food components during food processing”.

Correlating metabolomic data with epidemiological data may generate a comprehensive set of biological markers that can be useful in understanding and monitoring the interaction between food intake and human health, according to Tassoni.

“In particular, it could be possible to direct dietary habits to help prevent many widespread diseases, but also to create functional foods for particular groups of people who need a personalized diet”.

“Metabolomic data could be also employed to direct breeding and crop growth strategies to achieve desired balances of the plant food components used as raw materials in the food industry. This technology may also prove pivotal in optimizing food processing methods to help generate or preserve the nutritional balance of food through better packaging, storage conditions and spoilage prevention”.