Table 1: Trade-off between human health, food supply, and ecosystem health using the example of dietary protein
28
NUTRITION
macro- and micronutrients, e.g. the substitution of
saturated fat (from animal or palm fat) towards PUFA
from locally grown and produced rapeseed oil (e.g. in
margarine or convenient food items).
Trend two: Personalization of dietary
recommendations – how realistic is it?
Personalized nutrition is a concept that adjusts the nutritional
intake of food components to the actual need
of an individual person. In addition, it can also be applied
for achieving certain personal physiological goals
by individually adapting dietary behaviour and nutrition
9. These goals can be related to metabolic health
such as weight management, decrease of blood pressure,
or cholesterol levels, but also to increased performance
such as gaining improved endurance, strength,
or attention. However, for adjusting dietary uptake
or performance, reasonable measurements reflecting
individual metabolic constitutions or biological states
(biomarker) are needed. Reasonable biomarkers are
also characterized by their simple and reliable determination
procedure. However, very often the causes of
the same metabolic disturbance can be manifold. E.g.
impaired blood glucose levels are easily measurable,
but cannot be easily related to the responsible physiological
condition. They can be caused by impaired
glucose tolerance of the muscle, by impaired hepatic
glucose production, or by impaired glucose-stimulated
insulin secretion from the pancreas 9. In this case,
additional metabolic challenge tests are required.
Only then the cause of metabolic impairment can be
identified
and respective nutritional strategies could
be applied. Also other systemic impairments such as
the accumulation of inflammatory cytokines in several
tissues (e.g. inflammaging developing with rising age)
can cause changes in metabolic handling of glucose,
but need to be targeted by a different dietary regimen.
This complexity of physiological processes in addition
to the individually acting metabolic flexibility to keep
homeostasis under constantly changing conditions (as
with food intake) aggravates the identification of valid
biomarkers. In addition, when heading for a metabolic
or constitutional normalization by personalized nutrition,
the healthy control state need to be clearly defined.
This is mainly done though epidemiological studies
identifying associations between a dietary pattern
and known biomarkers of metabolic constitution, but
cannot be based on a proven causal relationship.
However, metabolically similar sub-phenotypes
could be identified by careful characterization of eating
habits, lifestyle factors, and evaluation of known
biomarkers. For this approach, more recently the term:
precision nutrition has been coined (in tight analogy to
‘personalized medicine’ or ‘precision medicine’). Here
groups of people characterized by the same parameters,
such as age, sex, lifestyle, biomarkers etc., will be
given nutritional recommendation in order to achieve
certain goals, e.g. maintaining weight and performance,
increasing muscle mass or others. Currently,
many funding bodies are involved in the determination
of health and nutrition characteristics in various age
groups using biomarkers as a tool. So, the EU project
MARK-AGE determined some hundred biomarkers in
the age group of 35 to 65 10, whereas the EU project
FRAILOMIC determined the markers of frailty in an age
group of 65 and above 11.
In conclusion, providing adequate personalized or
precise nutrition requires validated biomarkers or biomarker
clusters, a clear definition of the healthy metabolic
state, and a systems approach considering individual
metabolic flexibility of individuals. However, it seems
to us more likely that the concept of precise nutrition
will be more likely to take hold in the future and that
the current characterization (age, sex, body weight) will
be extended to more precise sub-group definitions. This
will be enabled of course by the current development
of technology, allowing large amounts of data to be
integrated and used for relevant conclusions.
Trend three: Nutrition –
sustainable or healthy?
This question describes a trade-off that integrates the
physiological demand of humans for being healthy,
issues of food production and technology as well as
consequences for the ecosystems of the planet. In the
current situation, the ecosystem earth is under a serious
threat and the awareness of many researchers, among
them many nutritionists, is high 12. In Table 1, several
aspects of the problem are displayed using the example
of dietary protein.
Human health Food supply Ecosystem health
• Essential amino acids
• Anabolic properties
• Beneficial effects of over- vs.
under-consumption
• Health effects
• Age dependency
• Protein sources (plant, animal,
alternative)
• Food matrix and bioavailability
• Processing and safety
• Production systems and management
• Resource endowment
• Greenhouse gas emissions
• Land and water use
• Soil degradation
• Air and water pollution
• Biodiversity loss