Functional Food concept
overview
That foods might provide therapeutic benefits is clearly not
a new concept. The tenet, “Let food be thy medicine and medicine be thy food”
was embraced ∼2500 years ago by Hippocrates, the father of medicine.
However, this “food as medicine” philosophy fell into relative obscurity in the 19th century
with the advent of modern drug therapy. In the 1900s, the important role of
diet in disease prevention and health promotion came to the forefront once
again.
In 1912, Casimir Funk presented a seminal paper proposing
the ‘Vitamine’ theory (McCollum, 1957). He proposed that the absence of certain
minute substances in foods rather than the presence of germs caused disease.
The theory and concept that he developed has had a direct bearing on the
development of functional foods. The concept of functional foods has now been
extended to include food constituents that reduce the risk of chronic disease
(Plat and Mensink, 2001). Today we are at a new frontier in nutritional
science. The transition from ‘adequate’ to ‘optimal’ nutrition. It is here that
functional foods will have a pivotal role in reducing diet-related chronic
diseases.
The conviction to develop functional foods first emerged in
Japan in the 1980s when faced with escalating health-care costs. The Ministry
of Health and Welfare initiated a regulatory system to approve certain foods
with documented health benefits (Arai, 1996). Its primary objective was to
improve the health of the nation's ageing population. In 1984, the Ministry of
Education, Science and Culture, an ad hoc group in Japan commenced a national
project to explore the link between food and medical sciences (Ohama et al.,
2006). The term ‘functional food’ first appeared in 1993 in the Nature news
magazine under the heading ‘Japan explores the boundary between food and
medicine’ (Swinbanks and O’Brien, 1993). [By www.nature.com]
Definitions for
functional foods
Today, Japan is the only country that recognizes functional
foods as a distinct category, and the Japanese functional food market is now
one of the most advanced in the world. Known as foods for specified health use
(FOSHU), these are foods composed of functional ingredients that affect the
structure and/or function of the body and are used to maintain or regulate
specific health conditions, such as gastrointestinal health, blood pressure and
blood cholesterol levels (Hosoya, 1998). As of July 2008, nearly 500 food
products had been granted FOSHU status in Japan.
Functional foods represent one of the most intensively
investigated and widely promoted areas in the food and nutrition sciences today
Functional food is essentially a marketing term and
globally, it is not recognized by law. Several definitions for functional foods
exist. These include, that given by Health Canada: ‘Similar in appearance to
conventional food, consumed as part of the usual diet, with demonstrated
physiological benefits, and/or to reduce the risk of chronic disease beyond
basic nutritional functions’ (Health Canada, 2000). Other definitions include
that from the International Food Information Council (IFIC), that is functional
foods are, ‘foods or dietary components that may provide a health benefit
beyond basic nutrition’ (Bagchi, 2008). The International Life Sciences
Institute of North America (ILSI) has defined functional foods as, ‘foods that
by virtue of physiologically active food components provide health benefits
beyond basic nutrition’ (Bagchi, 2008). The European Commission Concerted
Action on Functional Food Science in Europe regards a food as functional, ‘if
it is satisfactorily demonstrated to affect beneficially one or more target
functions in the body, beyond adequate nutritional effects, in a way that is
relevant to either an improved state of health and well-being and/or reduction
of risk of disease’ (Consensus document, 1999).
Functional foods represent one of the most intensively
investigated and widely promoted areas in the food and nutrition sciences
today. However, it must be emphasized that these foods and ingredients are not
magic bullets or panaceas for poor health habits. Diet is only one aspect of a
comprehensive approach to good health. functional foods health claims dietary
supplements phytochemicals bioactive
During the first 50 years of the 20th century, scientific
focus was on the identification of essential elements, particularly vitamins,
and their role in the prevention of various dietary deficiency diseases. This
emphasis on nutrient deficiencies or “undernutrition” shifted dramatically,
however, during the 1970s when diseases linked to excess and “overnutrition”
became a major public health concern. Thus began a flurry of public health
guidelines, including the Senate Select (McGovern) Committee’s Dietary Goals
for the United States (1977), the Dietary Guidelines for Americans (1980, 1985,
1990, 1996, 2000— a joint publication of the USDA and the Department of Health
and Human Services), the Surgeon General’s Report on Nutrition and Health
(1988), the National Research Council’s Diet and Health (1989) and Healthy
People 2000 and 2010 from the U.S. Public Health Service. All of these reports
are aimed at public policy and education emphasizing the importance of
consuming a diet that is low in saturated fat, and high in vegetables, fruits,
whole grains and legumes to reduce the risk of chronic diseases such as heart
disease, cancer, osteoporosis, diabetes and stroke.
Functional food
Health Benefits Discovery
Scientists also began to identify physiologically active
components in foods from both plants and animals (known as phytochemicals and
zoochemicals, respectively) that potentially could reduce risk for a variety of
chronic diseases. These events, coupled with an aging, health-conscious
population, changes in food regulations, numerous technological advances and a
marketplace ripe for the introduction of health-promoting products, coalesced
in the 1990s to create the trend we now know as “functional foods.” This report
includes a discussion of how functional foods are currently defined, the
strength of the evidence both required and thus far provided for many of these
products, safety considerations in using some of these products, factors
driving the functional foods phenomenon, and finally, what the future may hold
for this new food category.
According to the Department of Health and Human Services,
diet plays a role in 5 of 10 of the leading causes of death, including coronary
heart disease (CHD), certain types of cancer, stroke, diabetes (noninsulin
dependent or type 2) and atherosclerosis. The dietary pattern that has been
linked with these major causes of death in the United States and other
developed countries is characterized as relatively high in total and saturated
fat, cholesterol, sodium and refined sugars and relatively low in unsaturated
fat, grains, legumes, fruits and vegetables. An accumulating body of research
now suggests that consumption of certain foods or their associated
physiologically active components may be linked to disease risk reduction (6).
The great majority of these components derive from plants; however, there are
several classes of physiologically active functional food ingredients of animal
or microbial origin.
Claims linking the consumption of functional foods or food
ingredients with health outcomes require sound scientific evidence and
significant scientific agreement. The Food and Drug Administration (FDA)
outlined the criteria for “significant scientific agreement” in a guidance
document released on December 22, 1999 (7). As summarized in the schematic shown
in Figure 1, there is a clear discrepancy between “emerging evidence”
(characterized by in vitro or animal studies, uncontrolled human studies, and
inconsistent epidemiological evidence) and “significant scientific agreement.”
To reach such agreement requires the support of a body of consistent, relevant
evidence from well-designed clinical, epidemiologic and laboratory studies, and
expert opinions from a body of independent scientists. Claims about the health
benefits of functional foods should be based on sound scientific evidence, but
too often only so-called “emerging evidence” is the basis for marketing some
functional foods or their components. Table 1 categorizes a variety of
functional foods according to the type of evidence supporting their functionality,
the strength of that evidence and the recommended intake levels.
The FDA’s schematic of significant scientific agreement
released in December 22, 1999 guidance document. This scheme differentiates
“emerging evidence” on the left (e.g., animal and in vitro studies,
uncontrolled human studies) from data on the right which represents “consensus”
and includes evidence accepted by federal scientific bodies responsible for
public health recommendations. Thus, the strength of the evidence for a diet disease
relationship strengthens as one moves from left to right on the schematic. [
From By
http://jn.nutrition.org]
the
First book to offer the ways how to apply different functional foods to cope with
kinds of chronic diseases
